Commit graph

272 commits

Author SHA1 Message Date
HyukjinKwon 6ab29b37cf [SPARK-32179][SPARK-32188][PYTHON][DOCS] Replace and redesign the documentation base
### What changes were proposed in this pull request?

This PR proposes to redesign the PySpark documentation.

I made a demo site to make it easier to review: https://hyukjin-spark.readthedocs.io/en/stable/reference/index.html.

Here is the initial draft for the final PySpark docs shape: https://hyukjin-spark.readthedocs.io/en/latest/index.html.

In more details, this PR proposes:
1. Use [pydata_sphinx_theme](https://github.com/pandas-dev/pydata-sphinx-theme) theme - [pandas](https://pandas.pydata.org/docs/) and [Koalas](https://koalas.readthedocs.io/en/latest/) use this theme. The CSS overwrite is ported from Koalas. The colours in the CSS were actually chosen by designers to use in Spark.
2. Use the Sphinx option to separate `source` and `build` directories as the documentation pages will likely grow.
3. Port current API documentation into the new style. It mimics Koalas and pandas to use the theme most effectively.

    One disadvantage of this approach is that you should list up APIs or classes; however, I think this isn't a big issue in PySpark since we're being conservative on adding APIs. I also intentionally listed classes only instead of functions in ML and MLlib to make it relatively easier to manage.

### Why are the changes needed?

Often I hear the complaints, from the users, that current PySpark documentation is pretty messy to read - https://spark.apache.org/docs/latest/api/python/index.html compared other projects such as [pandas](https://pandas.pydata.org/docs/) and [Koalas](https://koalas.readthedocs.io/en/latest/).

It would be nicer if we can make it more organised instead of just listing all classes, methods and attributes to make it easier to navigate.

Also, the documentation has been there from almost the very first version of PySpark. Maybe it's time to update it.

### Does this PR introduce _any_ user-facing change?

Yes, PySpark API documentation will be redesigned.

### How was this patch tested?

Manually tested, and the demo site was made to show.

Closes #29188 from HyukjinKwon/SPARK-32179.

Authored-by: HyukjinKwon <gurwls223@apache.org>
Signed-off-by: HyukjinKwon <gurwls223@apache.org>
2020-07-27 17:49:21 +09:00
Takuya UESHIN 7b66882c9d [SPARK-32338][SQL][PYSPARK][FOLLOW-UP] Update slice to accept Column for start and length
### What changes were proposed in this pull request?

This is a follow-up of #29138 which added overload `slice` function to accept `Column` for `start` and `length` in Scala.

This PR is updating the equivalent Python function to accept `Column` as well.

### Why are the changes needed?

Now that Scala version accepts `Column`, Python version should also accept it.

### Does this PR introduce _any_ user-facing change?

Yes, PySpark users will also be able to pass Column object to `start` and `length` parameter in `slice` function.

### How was this patch tested?

Added tests.

Closes #29195 from ueshin/issues/SPARK-32338/slice.

Authored-by: Takuya UESHIN <ueshin@databricks.com>
Signed-off-by: HyukjinKwon <gurwls223@apache.org>
2020-07-23 13:53:50 +09:00
zero323 ef3cad17a6 [SPARK-29157][SQL][PYSPARK] Add DataFrameWriterV2 to Python API
### What changes were proposed in this pull request?

- Adds `DataFramWriterV2` class.
- Adds `writeTo` method to `pyspark.sql.DataFrame`.
- Adds related SQL partitioning functions (`years`, `months`, ..., `bucket`).

### Why are the changes needed?

Feature parity.

### Does this PR introduce any user-facing change?

No.

### How was this patch tested?

Added new unit tests.

TODO: Should we test against `org.apache.spark.sql.connector.InMemoryTableCatalog`? If so, how to expose it in Python tests?

Closes #27331 from zero323/SPARK-29157.

Authored-by: zero323 <mszymkiewicz@gmail.com>
Signed-off-by: HyukjinKwon <gurwls223@apache.org>
2020-07-20 10:42:33 +09:00
Erik Krogen cf22d947fb [SPARK-32036] Replace references to blacklist/whitelist language with more appropriate terminology, excluding the blacklisting feature
### What changes were proposed in this pull request?

This PR will remove references to these "blacklist" and "whitelist" terms besides the blacklisting feature as a whole, which can be handled in a separate JIRA/PR.

This touches quite a few files, but the changes are straightforward (variable/method/etc. name changes) and most quite self-contained.

### Why are the changes needed?

As per discussion on the Spark dev list, it will be beneficial to remove references to problematic language that can alienate potential community members. One such reference is "blacklist" and "whitelist". While it seems to me that there is some valid debate as to whether these terms have racist origins, the cultural connotations are inescapable in today's world.

### Does this PR introduce _any_ user-facing change?

In the test file `HiveQueryFileTest`, a developer has the ability to specify the system property `spark.hive.whitelist` to specify a list of Hive query files that should be tested. This system property has been renamed to `spark.hive.includelist`. The old property has been kept for compatibility, but will log a warning if used. I am open to feedback from others on whether keeping a deprecated property here is unnecessary given that this is just for developers running tests.

### How was this patch tested?

Existing tests should be suitable since no behavior changes are expected as a result of this PR.

Closes #28874 from xkrogen/xkrogen-SPARK-32036-rename-blacklists.

Authored-by: Erik Krogen <ekrogen@linkedin.com>
Signed-off-by: Thomas Graves <tgraves@apache.org>
2020-07-15 11:40:55 -05:00
HyukjinKwon 4ad9bfd53b [SPARK-32138] Drop Python 2.7, 3.4 and 3.5
### What changes were proposed in this pull request?

This PR aims to drop Python 2.7, 3.4 and 3.5.

Roughly speaking, it removes all the widely known Python 2 compatibility workarounds such as `sys.version` comparison, `__future__`. Also, it removes the Python 2 dedicated codes such as `ArrayConstructor` in Spark.

### Why are the changes needed?

 1. Unsupport EOL Python versions
 2. Reduce maintenance overhead and remove a bit of legacy codes and hacks for Python 2.
 3. PyPy2 has a critical bug that causes a flaky test, SPARK-28358 given my testing and investigation.
 4. Users can use Python type hints with Pandas UDFs without thinking about Python version
 5. Users can leverage one latest cloudpickle, https://github.com/apache/spark/pull/28950. With Python 3.8+ it can also leverage C pickle.

### Does this PR introduce _any_ user-facing change?

Yes, users cannot use Python 2.7, 3.4 and 3.5 in the upcoming Spark version.

### How was this patch tested?

Manually tested and also tested in Jenkins.

Closes #28957 from HyukjinKwon/SPARK-32138.

Authored-by: HyukjinKwon <gurwls223@apache.org>
Signed-off-by: HyukjinKwon <gurwls223@apache.org>
2020-07-14 11:22:44 +09:00
Max Gekk dd03c31ea5 [SPARK-32088][PYTHON][FOLLOWUP] Replace collect() by show() in the example for timestamp_seconds
### What changes were proposed in this pull request?
Modify the example for `timestamp_seconds` and replace `collect()` by `show()`.

### Why are the changes needed?
The SQL config `spark.sql.session.timeZone` doesn't influence on the `collect` in the example. The code below demonstrates that:
```
$ export TZ="UTC"
```
```python
>>> from pyspark.sql.functions import timestamp_seconds
>>> spark.conf.set("spark.sql.session.timeZone", "America/Los_Angeles")
>>> time_df = spark.createDataFrame([(1230219000,)], ['unix_time'])
>>> time_df.select(timestamp_seconds(time_df.unix_time).alias('ts')).collect()
[Row(ts=datetime.datetime(2008, 12, 25, 15, 30))]
```
The expected time is **07:30 but we get 15:30**.

### Does this PR introduce _any_ user-facing change?
No

### How was this patch tested?
By running the modified example via:
```
$ ./python/run-tests --modules=pyspark-sql
```

Closes #28959 from MaxGekk/SPARK-32088-fix-timezone-issue-followup.

Authored-by: Max Gekk <max.gekk@gmail.com>
Signed-off-by: HyukjinKwon <gurwls223@apache.org>
2020-07-01 13:17:49 +09:00
GuoPhilipse ac3a0551d8 [SPARK-32088][PYTHON] Pin the timezone in timestamp_seconds doctest
### What changes were proposed in this pull request?

Add American timezone during timestamp_seconds doctest

### Why are the changes needed?

`timestamp_seconds` doctest in `functions.py` used default timezone to get expected result
For example:

```python
>>> time_df = spark.createDataFrame([(1230219000,)], ['unix_time'])
>>> time_df.select(timestamp_seconds(time_df.unix_time).alias('ts')).collect()
[Row(ts=datetime.datetime(2008, 12, 25, 7, 30))]
```

But when we have a non-american timezone, the test case will get different test result.

For example, when we set current timezone as `Asia/Shanghai`, the test result will be

```
[Row(ts=datetime.datetime(2008, 12, 25, 23, 30))]
```

So no matter where we run the test case ,we will always get the expected permanent result if we set the timezone on one specific area.

### Does this PR introduce _any_ user-facing change?

No

### How was this patch tested?

Unit test

Closes #28932 from GuoPhilipse/SPARK-32088-fix-timezone-issue.

Lead-authored-by: GuoPhilipse <46367746+GuoPhilipse@users.noreply.github.com>
Co-authored-by: GuoPhilipse <guofei_ok@126.com>
Signed-off-by: Dongjoon Hyun <dongjoon@apache.org>
2020-06-26 19:06:31 -07:00
GuoPhilipse f0e6d0ec13 [SPARK-31710][SQL] Fail casting numeric to timestamp by default
## What changes were proposed in this pull request?
we fail casting from numeric to timestamp by default.

## Why are the changes needed?
casting from numeric to timestamp is not a  non-standard,meanwhile it may generate different result between spark and other systems,for example hive

## Does this PR introduce any user-facing change?
Yes,user cannot cast numeric to timestamp directly,user have to use the following function to achieve the same effect:TIMESTAMP_SECONDS/TIMESTAMP_MILLIS/TIMESTAMP_MICROS

## How was this patch tested?
unit test added

Closes #28593 from GuoPhilipse/31710-fix-compatibility.

Lead-authored-by: GuoPhilipse <guofei_ok@126.com>
Co-authored-by: GuoPhilipse <46367746+GuoPhilipse@users.noreply.github.com>
Signed-off-by: Wenchen Fan <wenchen@databricks.com>
2020-06-16 08:35:35 +00:00
Ben Ryves fa37856710 [SPARK-31306][DOCS] update rand() function documentation to indicate exclusive upper bound
### What changes were proposed in this pull request?
A small documentation change to clarify that the `rand()` function produces values in `[0.0, 1.0)`.

### Why are the changes needed?
`rand()` uses `Rand()` - which generates values in [0, 1) ([documented here](a1dbcd13a3/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/expressions/randomExpressions.scala (L71))). The existing documentation suggests that 1.0 is a possible value returned by rand (i.e for a distribution written as `X ~ U(a, b)`, x can be a or b, so `U[0.0, 1.0]` suggests the value returned could include 1.0).

### Does this PR introduce any user-facing change?
Only documentation changes.

### How was this patch tested?
Documentation changes only.

Closes #28071 from Smeb/master.

Authored-by: Ben Ryves <benjamin.ryves@getyourguide.com>
Signed-off-by: HyukjinKwon <gurwls223@apache.org>
2020-03-31 15:16:17 +09:00
Maxim Gekk d2ff5c5bfb [SPARK-31286][SQL][DOC] Specify formats of time zone ID for JSON/CSV option and from/to_utc_timestamp
### What changes were proposed in this pull request?
In the PR, I propose to update the doc for the `timeZone` option in JSON/CSV datasources and for the `tz` parameter of the `from_utc_timestamp()`/`to_utc_timestamp()` functions, and to restrict format of config's values to 2 forms:
1. Geographical regions, such as `America/Los_Angeles`.
2. Fixed offsets - a fully resolved offset from UTC. For example, `-08:00`.

### Why are the changes needed?
Other formats such as three-letter time zone IDs are ambitious, and depend on the locale. For example, `CST` could be U.S. `Central Standard Time` and `China Standard Time`. Such formats have been already deprecated in JDK, see [Three-letter time zone IDs](https://docs.oracle.com/javase/8/docs/api/java/util/TimeZone.html).

### Does this PR introduce any user-facing change?
No

### How was this patch tested?
By running `./dev/scalastyle`, and manual testing.

Closes #28051 from MaxGekk/doc-time-zone-option.

Authored-by: Maxim Gekk <max.gekk@gmail.com>
Signed-off-by: Wenchen Fan <wenchen@databricks.com>
2020-03-30 12:20:11 +08:00
gatorsmile 3884455780 [SPARK-31087] [SQL] Add Back Multiple Removed APIs
### What changes were proposed in this pull request?

Based on the discussion in the mailing list [[Proposal] Modification to Spark's Semantic Versioning Policy](http://apache-spark-developers-list.1001551.n3.nabble.com/Proposal-Modification-to-Spark-s-Semantic-Versioning-Policy-td28938.html) , this PR is to add back the following APIs whose maintenance cost are relatively small.

- functions.toDegrees/toRadians
- functions.approxCountDistinct
- functions.monotonicallyIncreasingId
- Column.!==
- Dataset.explode
- Dataset.registerTempTable
- SQLContext.getOrCreate, setActive, clearActive, constructors

Below is the other removed APIs in the original PR, but not added back in this PR [https://issues.apache.org/jira/browse/SPARK-25908]:

- Remove some AccumulableInfo .apply() methods
- Remove non-label-specific multiclass precision/recall/fScore in favor of accuracy
- Remove unused Python StorageLevel constants
- Remove unused multiclass option in libsvm parsing
- Remove references to deprecated spark configs like spark.yarn.am.port
- Remove TaskContext.isRunningLocally
- Remove ShuffleMetrics.shuffle* methods
- Remove BaseReadWrite.context in favor of session

### Why are the changes needed?
Avoid breaking the APIs that are commonly used.

### Does this PR introduce any user-facing change?
Adding back the APIs that were removed in 3.0 branch does not introduce the user-facing changes, because Spark 3.0 has not been released.

### How was this patch tested?
Added a new test suite for these APIs.

Author: gatorsmile <gatorsmile@gmail.com>
Author: yi.wu <yi.wu@databricks.com>

Closes #27821 from gatorsmile/addAPIBackV2.
2020-03-28 22:05:16 -07:00
Kent Yao b024a8a69e [MINOR][DOCS] Fix some links for python api doc
### What changes were proposed in this pull request?

the link for `partition discovery` is malformed, because for releases, there will contains` /docs/<version>/` in the full URL.

### Why are the changes needed?

fix doc

### Does this PR introduce any user-facing change?

no

### How was this patch tested?

`SKIP_SCALADOC=1 SKIP_RDOC=1 SKIP_SQLDOC=1 jekyll serve` locally verified

Closes #28017 from yaooqinn/doc.

Authored-by: Kent Yao <yaooqinn@hotmail.com>
Signed-off-by: HyukjinKwon <gurwls223@apache.org>
2020-03-26 13:06:21 +09:00
Kent Yao 88ae6c4481 [SPARK-31189][SQL][DOCS] Fix errors and missing parts for datetime pattern document
### What changes were proposed in this pull request?

Fix errors and missing parts for datetime pattern document
1. The pattern we use is similar to DateTimeFormatter and SimpleDateFormat but not identical. So we shouldn't use any of them in the API docs but use a link to the doc of our own.
2. Some pattern letters are missing
3. Some pattern letters are explicitly banned - Set('A', 'c', 'e', 'n', 'N')
4. the second fraction pattern different logic for parsing and formatting

### Why are the changes needed?

fix and improve doc
### Does this PR introduce any user-facing change?

yes, new and updated doc
### How was this patch tested?

pass Jenkins
viewed locally with `jekyll serve`
![image](https://user-images.githubusercontent.com/8326978/77044447-6bd3bb00-69fa-11ea-8d6f-7084166c5dea.png)

Closes #27956 from yaooqinn/SPARK-31189.

Authored-by: Kent Yao <yaooqinn@hotmail.com>
Signed-off-by: Wenchen Fan <wenchen@databricks.com>
2020-03-20 21:59:26 +08:00
zero323 01f20394ac [SPARK-30569][SQL][PYSPARK][SPARKR] Add percentile_approx DSL functions
### What changes were proposed in this pull request?

- Adds following overloaded variants to Scala `o.a.s.sql.functions`:

  - `percentile_approx(e: Column, percentage: Array[Double], accuracy: Long): Column`
  - `percentile_approx(columnName: String, percentage: Array[Double], accuracy: Long): Column`
  - `percentile_approx(e: Column, percentage: Double, accuracy: Long): Column`
  - `percentile_approx(columnName: String, percentage: Double, accuracy: Long): Column`
  - `percentile_approx(e: Column, percentage: Seq[Double], accuracy: Long): Column` (primarily for
Python interop).
  - `percentile_approx(columnName: String, percentage: Seq[Double], accuracy: Long): Column`

- Adds `percentile_approx` to `pyspark.sql.functions`.

- Adds `percentile_approx` function to SparkR.

### Why are the changes needed?

Currently we support `percentile_approx` only in SQL expression. It is inconvenient and makes this function relatively unknown.

### Does this PR introduce any user-facing change?

No.

### How was this patch tested?

New unit tests for SparkR an PySpark.

As for now there are no additional tests in Scala API ‒ `ApproximatePercentile` is well tested and Python (including docstrings) and R tests provide additional tests, so it seems unnecessary.

Closes #27278 from zero323/SPARK-30569.

Lead-authored-by: zero323 <mszymkiewicz@gmail.com>
Co-authored-by: HyukjinKwon <gurwls223@apache.org>
Signed-off-by: HyukjinKwon <gurwls223@apache.org>
2020-03-17 10:44:21 +09:00
Yuanjian Li 3493162c78 [SPARK-31030][SQL] Backward Compatibility for Parsing and formatting Datetime
### What changes were proposed in this pull request?
In Spark version 2.4 and earlier, datetime parsing, formatting and conversion are performed by using the hybrid calendar (Julian + Gregorian).
Since the Proleptic Gregorian calendar is de-facto calendar worldwide, as well as the chosen one in ANSI SQL standard, Spark 3.0 switches to it by using Java 8 API classes (the java.time packages that are based on ISO chronology ). The switching job is completed in SPARK-26651.
But after the switching, there are some patterns not compatible between Java 8 and Java 7, Spark needs its own definition on the patterns rather than depends on Java API.
In this PR, we achieve this by writing the document and shadow the incompatible letters. See more details in [SPARK-31030](https://issues.apache.org/jira/browse/SPARK-31030)

### Why are the changes needed?
For backward compatibility.

### Does this PR introduce any user-facing change?
No.
After we define our own datetime parsing and formatting patterns, it's same to old Spark version.

### How was this patch tested?
Existing and new added UT.
Locally document test:
![image](https://user-images.githubusercontent.com/4833765/76064100-f6acc280-5fc3-11ea-9ef7-82e7dc074205.png)

Closes #27830 from xuanyuanking/SPARK-31030.

Authored-by: Yuanjian Li <xyliyuanjian@gmail.com>
Signed-off-by: Wenchen Fan <wenchen@databricks.com>
2020-03-11 14:11:13 +08:00
zero323 7de33f56e8 [SPARK-30681][PYSPARK][SQL] Add higher order functions API to PySpark
### What changes were proposed in this pull request?

This PR add Python API for invoking following higher functions:

- `transform`
- `exists`
- `forall`
- `filter`
- `aggregate`
- `zip_with`
- `transform_keys`
- `transform_values`
- `map_filter`
- `map_zip_with`

to `pyspark.sql`. Each of these accepts plain Python functions of one of the following types

- `(Column) -> Column: ...`
- `(Column, Column) -> Column: ...`
- `(Column, Column, Column) -> Column: ...`

Internally this proposal piggbacks on objects supporting Scala implementation ([SPARK-27297](https://issues.apache.org/jira/browse/SPARK-27297)) by:

1. Creating  required `UnresolvedNamedLambdaVariables`  exposing these as PySpark `Columns`
2. Invoking Python function with these columns as arguments.
3. Using the result, and underlying JVM objects from 1., to create `expressions.LambdaFunction` which is passed to desired expression, and repacked as Python `Column`.

### Why are the changes needed?

Currently higher order functions are available only using SQL and Scala API and can use only SQL expressions

```python
df.selectExpr("transform(values, x -> x + 1)")
```

This works reasonably well for simple functions, but can get really ugly with complex functions (complex functions, casts), resulting objects are somewhat verbose and we don't get any IDE support.  Additionally DSL used, though  very simple, is not documented.

With changes propose here, above query could be rewritten as:

```python
df.select(transform("values", lambda x: x + 1))
```

### Does this PR introduce any user-facing change?

No.

### How was this patch tested?

- For positive cases this PR adds doctest strings covering possible usage patterns.
- For negative cases (unsupported function types) this PR adds unit tests.

### Notes

If approved, the same approach can be used in SparkR.

Closes #27406 from zero323/SPARK-30681.

Authored-by: zero323 <mszymkiewicz@gmail.com>
Signed-off-by: HyukjinKwon <gurwls223@apache.org>
2020-02-28 12:59:39 +09:00
David Toneian 504b5135d0 [SPARK-30859][PYSPARK][DOCS][MINOR] Fixed docstring syntax issues preventing proper compilation of documentation
This commit is published into the public domain.

### What changes were proposed in this pull request?
Some syntax issues in docstrings have been fixed.

### Why are the changes needed?
In some places, the documentation did not render as intended, e.g. parameter documentations were not formatted as such.

### Does this PR introduce any user-facing change?
Slight improvements in documentation.

### How was this patch tested?
Manual testing. No new Sphinx warnings arise due to this change.

Closes #27613 from DavidToneian/SPARK-30859.

Authored-by: David Toneian <david@toneian.com>
Signed-off-by: HyukjinKwon <gurwls223@apache.org>
2020-02-18 16:46:45 +09:00
Yuanjian Li ab186e3659 [SPARK-25829][SQL] Add config spark.sql.legacy.allowDuplicatedMapKeys and change the default behavior
### What changes were proposed in this pull request?
This is a follow-up for #23124, add a new config `spark.sql.legacy.allowDuplicatedMapKeys` to control the behavior of removing duplicated map keys in build-in functions. With the default value `false`, Spark will throw a RuntimeException while duplicated keys are found.

### Why are the changes needed?
Prevent silent behavior changes.

### Does this PR introduce any user-facing change?
Yes, new config added and the default behavior for duplicated map keys changed to RuntimeException thrown.

### How was this patch tested?
Modify existing UT.

Closes #27478 from xuanyuanking/SPARK-25892-follow.

Authored-by: Yuanjian Li <xyliyuanjian@gmail.com>
Signed-off-by: Wenchen Fan <wenchen@databricks.com>
2020-02-17 22:06:58 +08:00
Xiao Li d69ed9afdf Revert "[SPARK-25496][SQL] Deprecate from_utc_timestamp and to_utc_timestamp"
This reverts commit 1d20d13149.

Closes #27351 from gatorsmile/revertSPARK25496.

Authored-by: Xiao Li <gatorsmile@gmail.com>
Signed-off-by: Dongjoon Hyun <dhyun@apple.com>
2020-01-25 21:34:12 -08:00
Deepyaman Datta 53fd83a8c5 [MINOR][DOCS] Fix src/dest type documentation for to_timestamp
### What changes were proposed in this pull request?

Minor documentation fix

### Why are the changes needed?

### Does this PR introduce any user-facing change?

### How was this patch tested?

Manually; consider adding tests?

Closes #27295 from deepyaman/patch-2.

Authored-by: Deepyaman Datta <deepyaman.datta@utexas.edu>
Signed-off-by: HyukjinKwon <gurwls223@apache.org>
2020-01-24 13:10:09 +09:00
zero323 2330a5682d [SPARK-30607][SQL][PYSPARK][SPARKR] Add overlay wrappers for SparkR and PySpark
### What changes were proposed in this pull request?

This PR adds:

- `pyspark.sql.functions.overlay` function to PySpark
- `overlay` function to SparkR

### Why are the changes needed?

Feature parity. At the moment R and Python users can access this function only using SQL or `expr` / `selectExpr`.

### Does this PR introduce any user-facing change?

No.

### How was this patch tested?

New unit tests.

Closes #27325 from zero323/SPARK-30607.

Authored-by: zero323 <mszymkiewicz@gmail.com>
Signed-off-by: HyukjinKwon <gurwls223@apache.org>
2020-01-23 16:16:47 +09:00
HyukjinKwon ee8d661058 [SPARK-30434][PYTHON][SQL] Move pandas related functionalities into 'pandas' sub-package
### What changes were proposed in this pull request?

This PR proposes to move pandas related functionalities into pandas package. Namely:

```bash
pyspark/sql/pandas
├── __init__.py
├── conversion.py  # Conversion between pandas <> PySpark DataFrames
├── functions.py   # pandas_udf
├── group_ops.py   # Grouped UDF / Cogrouped UDF + groupby.apply, groupby.cogroup.apply
├── map_ops.py     # Map Iter UDF + mapInPandas
├── serializers.py # pandas <> PyArrow serializers
├── types.py       # Type utils between pandas <> PyArrow
└── utils.py       # Version requirement checks
```

In order to separately locate `groupby.apply`, `groupby.cogroup.apply`, `mapInPandas`, `toPandas`, and `createDataFrame(pdf)` under `pandas` sub-package, I had to use a mix-in approach which Scala side uses often by `trait`, and also pandas itself uses this approach (see `IndexOpsMixin` as an example) to group related functionalities. Currently, you can think it's like Scala's self typed trait. See the structure below:

```python
class PandasMapOpsMixin(object):
    def mapInPandas(self, ...):
        ...
        return ...

    # other Pandas <> PySpark APIs
```

```python
class DataFrame(PandasMapOpsMixin):

    # other DataFrame APIs equivalent to Scala side.

```

Yes, This is a big PR but they are mostly just moving around except one case `createDataFrame` which I had to split the methods.

### Why are the changes needed?

There are pandas functionalities here and there and I myself gets lost where it was. Also, when you have to make a change commonly for all of pandas related features, it's almost impossible now.

Also, after this change, `DataFrame` and `SparkSession` become more consistent with Scala side since pandas is specific to Python, and this change separates pandas-specific APIs away from `DataFrame` or `SparkSession`.

### Does this PR introduce any user-facing change?

No.

### How was this patch tested?

Existing tests should cover. Also, I manually built the PySpark API documentation and checked.

Closes #27109 from HyukjinKwon/pandas-refactoring.

Authored-by: HyukjinKwon <gurwls223@apache.org>
Signed-off-by: HyukjinKwon <gurwls223@apache.org>
2020-01-09 10:22:50 +09:00
HyukjinKwon 866b7df348 [SPARK-30335][SQL][DOCS] Add a note first, last, collect_list and collect_set can be non-deterministic in SQL function docs as well
### What changes were proposed in this pull request?
This PR adds a note first and last can be non-deterministic in SQL function docs as well.
This is already documented in `functions.scala`.

### Why are the changes needed?
Some people look reading SQL docs only.

### Does this PR introduce any user-facing change?
No

### How was this patch tested?
Jenkins will test.

Closes #27099 from HyukjinKwon/SPARK-30335.

Authored-by: HyukjinKwon <gurwls223@apache.org>
Signed-off-by: HyukjinKwon <gurwls223@apache.org>
2020-01-07 14:31:59 +09:00
Boris Boutkov 3bf5498b4a [MINOR][DOCS] Fix documentation for slide function
### What changes were proposed in this pull request?

This PR proposes to fix documentation for slide function. Fixed the spacing issue and added some parameter related info.

### Why are the changes needed?

Documentation improvement

### Does this PR introduce any user-facing change?

No (doc-only change).

### How was this patch tested?

Manually tested by documentation build.

Closes #26896 from bboutkov/pyspark_doc_fix.

Authored-by: Boris Boutkov <boris.boutkov@gmail.com>
Signed-off-by: HyukjinKwon <gurwls223@apache.org>
2019-12-16 16:29:09 +09:00
Chris Martin c29494377b [SPARK-29126][PYSPARK][DOC] Pandas Cogroup udf usage guide
This PR adds some extra documentation for the new Cogrouped map Pandas udfs.  Specifically:

- Updated the usage guide for the new `COGROUPED_MAP` Pandas udfs added in https://github.com/apache/spark/pull/24981
- Updated the docstring for pandas_udf to include the COGROUPED_MAP type as suggested by HyukjinKwon in https://github.com/apache/spark/pull/25939

Closes #26110 from d80tb7/SPARK-29126-cogroup-udf-usage-guide.

Authored-by: Chris Martin <chris@cmartinit.co.uk>
Signed-off-by: HyukjinKwon <gurwls223@apache.org>
2019-10-31 10:41:57 +09:00
HyukjinKwon 8682bb11ae [SPARK-29627][PYTHON][SQL] Allow array_contains to take column instances
### What changes were proposed in this pull request?

This PR proposes to allow `array_contains` to take column instances.

### Why are the changes needed?

For consistent support in Scala and Python APIs. Scala allows column instances at `array_contains`

Scala:

```scala
import org.apache.spark.sql.functions._
val df = Seq(Array("a", "b", "c"), Array.empty[String]).toDF("data")
df.select(array_contains($"data", lit("a"))).show()
```

Python:

```python
from pyspark.sql.functions import array_contains, lit
df = spark.createDataFrame([(["a", "b", "c"],), ([],)], ['data'])
df.select(array_contains(df.data, lit("a"))).show()
```

However, PySpark sides does not allow.

### Does this PR introduce any user-facing change?

Yes.

```python
from pyspark.sql.functions import array_contains, lit
df = spark.createDataFrame([(["a", "b", "c"],), ([],)], ['data'])
df.select(array_contains(df.data, lit("a"))).show()
```

**Before:**

```
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "/.../spark/python/pyspark/sql/functions.py", line 1950, in array_contains
    return Column(sc._jvm.functions.array_contains(_to_java_column(col), value))
  File "/.../spark/python/lib/py4j-0.10.8.1-src.zip/py4j/java_gateway.py", line 1277, in __call__
  File "/.../spark/python/lib/py4j-0.10.8.1-src.zip/py4j/java_gateway.py", line 1241, in _build_args
  File "/.../spark/python/lib/py4j-0.10.8.1-src.zip/py4j/java_gateway.py", line 1228, in _get_args
  File "/.../spark/python/lib/py4j-0.10.8.1-src.zip/py4j/java_collections.py", line 500, in convert
  File "/.../spark/python/pyspark/sql/column.py", line 344, in __iter__
    raise TypeError("Column is not iterable")
TypeError: Column is not iterable
```

**After:**

```
+-----------------------+
|array_contains(data, a)|
+-----------------------+
|                   true|
|                  false|
+-----------------------+
```

### How was this patch tested?

Manually tested and added a doctest.

Closes #26288 from HyukjinKwon/SPARK-29627.

Authored-by: HyukjinKwon <gurwls223@apache.org>
Signed-off-by: HyukjinKwon <gurwls223@apache.org>
2019-10-30 09:45:19 +09:00
HyukjinKwon fda0e6e48d [SPARK-29240][PYTHON] Pass Py4J column instance to support PySpark column in element_at function
### What changes were proposed in this pull request?

This PR makes `element_at` in PySpark able to take PySpark `Column` instances.

### Why are the changes needed?

To match with Scala side. Seems it was intended but not working correctly as a bug.

### Does this PR introduce any user-facing change?

Yes. See below:

```python
from pyspark.sql import functions as F
x = spark.createDataFrame([([1,2,3],1),([4,5,6],2),([7,8,9],3)],['list','num'])
x.withColumn('aa',F.element_at('list',x.num.cast('int'))).show()
```

Before:

```
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "/.../spark/python/pyspark/sql/functions.py", line 2059, in element_at
    return Column(sc._jvm.functions.element_at(_to_java_column(col), extraction))
  File "/.../spark/python/lib/py4j-0.10.8.1-src.zip/py4j/java_gateway.py", line 1277, in __call__
  File "/.../spark/python/lib/py4j-0.10.8.1-src.zip/py4j/java_gateway.py", line 1241, in _build_args
  File "/.../spark/python/lib/py4j-0.10.8.1-src.zip/py4j/java_gateway.py", line 1228, in _get_args
  File "/.../forked/spark/python/lib/py4j-0.10.8.1-src.zip/py4j/java_collections.py", line 500, in convert
  File "/.../spark/python/pyspark/sql/column.py", line 344, in __iter__
    raise TypeError("Column is not iterable")
TypeError: Column is not iterable
```

After:

```
+---------+---+---+
|     list|num| aa|
+---------+---+---+
|[1, 2, 3]|  1|  1|
|[4, 5, 6]|  2|  5|
|[7, 8, 9]|  3|  9|
+---------+---+---+
```

### How was this patch tested?

Manually tested against literal, Python native types, and PySpark column.

Closes #25950 from HyukjinKwon/SPARK-29240.

Authored-by: HyukjinKwon <gurwls223@apache.org>
Signed-off-by: Dongjoon Hyun <dhyun@apple.com>
2019-09-27 11:04:55 -07:00
sheepstop 81de9d3c29 [SPARK-28678][DOC] Specify that array indices start at 1 for function slice in R Scala Python
### What changes were proposed in this pull request?
Added "array indices start at 1" in annotation to make it clear for the usage of function slice, in R Scala Python component

### Why are the changes needed?
It will throw exception if the value stare is 0, but array indices start at 0 most of times in other scenarios.

### Does this PR introduce any user-facing change?
Yes, more info provided to user.

### How was this patch tested?
No tests added, only doc change.

Closes #25704 from sheepstop/master.

Authored-by: sheepstop <yangting617@gmail.com>
Signed-off-by: HyukjinKwon <gurwls223@apache.org>
2019-09-24 18:57:54 +09:00
Chris Martin 05988b256e [SPARK-27463][PYTHON] Support Dataframe Cogroup via Pandas UDFs
### What changes were proposed in this pull request?

Adds a new cogroup Pandas UDF.  This allows two grouped dataframes to be cogrouped together and apply a (pandas.DataFrame, pandas.DataFrame) -> pandas.DataFrame UDF to each cogroup.

**Example usage**

```
from pyspark.sql.functions import pandas_udf, PandasUDFType
df1 = spark.createDataFrame(
   [(20000101, 1, 1.0), (20000101, 2, 2.0), (20000102, 1, 3.0), (20000102, 2, 4.0)],
   ("time", "id", "v1"))

df2 = spark.createDataFrame(
   [(20000101, 1, "x"), (20000101, 2, "y")],
    ("time", "id", "v2"))

pandas_udf("time int, id int, v1 double, v2 string", PandasUDFType.COGROUPED_MAP)
   def asof_join(l, r):
      return pd.merge_asof(l, r, on="time", by="id")

df1.groupby("id").cogroup(df2.groupby("id")).apply(asof_join).show()

```

        +--------+---+---+---+
        |    time| id| v1| v2|
        +--------+---+---+---+
        |20000101|  1|1.0|  x|
        |20000102|  1|3.0|  x|
        |20000101|  2|2.0|  y|
        |20000102|  2|4.0|  y|
        +--------+---+---+---+

### How was this patch tested?

Added unit test test_pandas_udf_cogrouped_map

Closes #24981 from d80tb7/SPARK-27463-poc-arrow-stream.

Authored-by: Chris Martin <chris@cmartinit.co.uk>
Signed-off-by: Bryan Cutler <cutlerb@gmail.com>
2019-09-17 17:13:50 -07:00
Sean Owen eb037a8180 [SPARK-28855][CORE][ML][SQL][STREAMING] Remove outdated usages of Experimental, Evolving annotations
### What changes were proposed in this pull request?

The Experimental and Evolving annotations are both (like Unstable) used to express that a an API may change. However there are many things in the code that have been marked that way since even Spark 1.x. Per the dev thread, anything introduced at or before Spark 2.3.0 is pretty much 'stable' in that it would not change without a deprecation cycle. Therefore I'd like to remove most of these annotations. And, remove the `:: Experimental ::` scaladoc tag too. And likewise for Python, R.

The changes below can be summarized as:
- Generally, anything introduced at or before Spark 2.3.0 has been unmarked as neither Evolving nor Experimental
- Obviously experimental items like DSv2, Barrier mode, ExperimentalMethods are untouched
- I _did_ unmark a few MLlib classes introduced in 2.4, as I am quite confident they're not going to change (e.g. KolmogorovSmirnovTest, PowerIterationClustering)

It's a big change to review, so I'd suggest scanning the list of _files_ changed to see if any area seems like it should remain partly experimental and examine those.

### Why are the changes needed?

Many of these annotations are incorrect; the APIs are de facto stable. Leaving them also makes legitimate usages of the annotations less meaningful.

### Does this PR introduce any user-facing change?

No.

### How was this patch tested?

Existing tests.

Closes #25558 from srowen/SPARK-28855.

Authored-by: Sean Owen <sean.owen@databricks.com>
Signed-off-by: Sean Owen <sean.owen@databricks.com>
2019-09-01 10:15:00 -05:00
darrentirto a787bc2884 [SPARK-28777][PYTHON][DOCS] Fix format_string doc string with the correct parameters
### What changes were proposed in this pull request?
The parameters doc string of the function format_string was changed from _col_, _d_ to _format_, _cols_ which is what the actual function declaration states

### Why are the changes needed?
The parameters stated by the documentation was inaccurate

### Does this PR introduce any user-facing change?
Yes.

**BEFORE**
![before](https://user-images.githubusercontent.com/9700541/63310013-e21a0e80-c2ad-11e9-806b-1d272c5cde12.png)

**AFTER**
![after](https://user-images.githubusercontent.com/9700541/63315812-6b870c00-c2c1-11e9-8165-82782628cd1a.png)

### How was this patch tested?
N/A: documentation only
<!--
If tests were added, say they were added here. Please make sure to add some test cases that check the changes thoroughly including negative and positive cases if possible.
If it was tested in a way different from regular unit tests, please clarify how you tested step by step, ideally copy and paste-able, so that other reviewers can test and check, and descendants can verify in the future.
If tests were not added, please describe why they were not added and/or why it was difficult to add.
-->

Closes #25506 from darrentirto/SPARK-28777.

Authored-by: darrentirto <darrentirto@gmail.com>
Signed-off-by: Dongjoon Hyun <dhyun@apple.com>
2019-08-19 20:44:46 -07:00
Maxim Gekk a5a5da78cf [SPARK-28471][SQL] Replace yyyy by uuuu in date-timestamp patterns without era
## What changes were proposed in this pull request?

In the PR, I propose to use `uuuu` for years instead of `yyyy` in date/timestamp patterns without the era pattern `G` (https://docs.oracle.com/javase/8/docs/api/java/time/format/DateTimeFormatter.html). **Parsing/formatting of positive years (current era) will be the same.** The difference is in formatting negative years belong to previous era - BC (Before Christ).

I replaced the `yyyy` pattern by `uuuu` everywhere except:
1. Test, Suite & Benchmark. Existing tests must work as is.
2. `SimpleDateFormat` because it doesn't support the `uuuu` pattern.
3. Comments and examples (except comments related to already replaced patterns).

Before the changes, the year of common era `100` and the year of BC era `-99`, showed similarly as `100`.  After the changes negative years will be formatted with the `-` sign.

Before:
```Scala
scala> Seq(java.time.LocalDate.of(-99, 1, 1)).toDF().show
+----------+
|     value|
+----------+
|0100-01-01|
+----------+
```

After:
```Scala
scala> Seq(java.time.LocalDate.of(-99, 1, 1)).toDF().show
+-----------+
|      value|
+-----------+
|-0099-01-01|
+-----------+
```

## How was this patch tested?

By existing test suites, and added tests for negative years to `DateFormatterSuite` and `TimestampFormatterSuite`.

Closes #25230 from MaxGekk/year-pattern-uuuu.

Authored-by: Maxim Gekk <max.gekk@gmail.com>
Signed-off-by: Dongjoon Hyun <dhyun@apple.com>
2019-07-28 20:36:36 -07:00
zero323 a0c2fa63ab [SPARK-28439][PYTHON][SQL] Add support for count: Column in array_repeat
## What changes were proposed in this pull request?

This adds simple check for `count` argument:

- If it is a `Column` we apply `_to_java_column` before invoking JVM counterpart
- Otherwise we proceed as before.

## How was this patch tested?

Manual testing.

Closes #25193 from zero323/SPARK-28278.

Authored-by: zero323 <mszymkiewicz@gmail.com>
Signed-off-by: Dongjoon Hyun <dhyun@apple.com>
2019-07-18 12:58:48 -07:00
Maxim Gekk 70073b19eb [SPARK-27609][PYTHON] Convert values of function options to strings
## What changes were proposed in this pull request?

In the PR, I propose to convert options values to strings by using `to_str()` for the following functions:  `from_csv()`, `to_csv()`, `from_json()`, `to_json()`, `schema_of_csv()` and `schema_of_json()`. This will make handling of function options consistent to option handling in `DataFrameReader`/`DataFrameWriter`.

For example:
```Python
df.select(from_csv(df.value, "s string", {'ignoreLeadingWhiteSpace': True})
```

## How was this patch tested?

Added an example for `from_csv()` which was tested by:
```Shell
./python/run-tests --testnames pyspark.sql.functions
```

Closes #25182 from MaxGekk/options_to_str.

Authored-by: Maxim Gekk <max.gekk@gmail.com>
Signed-off-by: HyukjinKwon <gurwls223@apache.org>
2019-07-18 13:37:03 +09:00
HyukjinKwon cdbc30213b [SPARK-28226][PYTHON] Document Pandas UDF mapInPandas
## What changes were proposed in this pull request?

This PR proposes to document `MAP_ITER` with `mapInPandas`.

## How was this patch tested?

Manually checked the documentation.

![Screen Shot 2019-07-05 at 1 52 30 PM](https://user-images.githubusercontent.com/6477701/60698812-26cf2d80-9f2c-11e9-8295-9c00c28f5569.png)

![Screen Shot 2019-07-05 at 1 48 53 PM](https://user-images.githubusercontent.com/6477701/60698710-ac061280-9f2b-11e9-8521-a4f361207e06.png)

Closes #25025 from HyukjinKwon/SPARK-28226.

Authored-by: HyukjinKwon <gurwls223@apache.org>
Signed-off-by: HyukjinKwon <gurwls223@apache.org>
2019-07-07 09:07:52 +09:00
HyukjinKwon 5c55812400 [SPARK-28198][PYTHON][FOLLOW-UP] Rename mapPartitionsInPandas to mapInPandas with a separate evaluation type
## What changes were proposed in this pull request?

This PR proposes to rename `mapPartitionsInPandas` to `mapInPandas` with a separate evaluation type .

Had an offline discussion with rxin, mengxr and cloud-fan

The reason is basically:

1. `SCALAR_ITER` doesn't make sense with `mapPartitionsInPandas`.
2. It cannot share the same Pandas UDF, for instance, at `select` and `mapPartitionsInPandas` unlike `GROUPED_AGG` because iterator's return type is different.
3. `mapPartitionsInPandas` -> `mapInPandas` - see https://github.com/apache/spark/pull/25044#issuecomment-508298552 and https://github.com/apache/spark/pull/25044#issuecomment-508299764

Renaming `SCALAR_ITER` as `MAP_ITER` is abandoned due to 2. reason.

For `XXX_ITER`, it might have to have a different interface in the future if we happen to add other versions of them. But this is an orthogonal topic with `mapPartitionsInPandas`.

## How was this patch tested?

Existing tests should cover.

Closes #25044 from HyukjinKwon/SPARK-28198.

Authored-by: HyukjinKwon <gurwls223@apache.org>
Signed-off-by: HyukjinKwon <gurwls223@apache.org>
2019-07-05 09:22:41 +09:00
Xiangrui Meng 8299600575 [SPARK-28056][.2][PYTHON][SQL] add docstring/doctest for SCALAR_ITER Pandas UDF
## What changes were proposed in this pull request?

Add docstring/doctest for `SCALAR_ITER` Pandas UDF. I explicitly mentioned that per-partition execution is an implementation detail, not guaranteed. I will submit another PR to add the same to user guide, just to keep this PR minimal.

I didn't add "doctest: +SKIP" in the first commit so it is easy to test locally.

cc: HyukjinKwon gatorsmile icexelloss BryanCutler WeichenXu123

![Screen Shot 2019-06-28 at 9 52 41 AM](https://user-images.githubusercontent.com/829644/60358349-b0aa5400-998a-11e9-9ebf-8481dfd555b5.png)
![Screen Shot 2019-06-28 at 9 53 19 AM](https://user-images.githubusercontent.com/829644/60358355-b1db8100-998a-11e9-8f6f-00a11bdbdc4d.png)

## How was this patch tested?

doctest

Closes #25005 from mengxr/SPARK-28056.2.

Authored-by: Xiangrui Meng <meng@databricks.com>
Signed-off-by: gatorsmile <gatorsmile@gmail.com>
2019-06-28 15:09:57 -07:00
HyukjinKwon 113f8c8d13 [SPARK-28132][PYTHON] Update document type conversion for Pandas UDFs (pyarrow 0.13.0, pandas 0.24.2, Python 3.7)
## What changes were proposed in this pull request?

This PR updates the chart generated at SPARK-25666. We deprecated Python 2. It's better to use Python 3.

We don't have to test `unicode` and `long` anymore in Python 3. So it was removed.

Use this code to generate the chart:

```python
from pyspark.sql.types import *
from pyspark.sql.functions import pandas_udf

columns = [
    ('none', 'object(NoneType)'),
    ('bool', 'bool'),
    ('int8', 'int8'),
    ('int16', 'int16'),
    ('int32', 'int32'),
    ('int64', 'int64'),
    ('uint8', 'uint8'),
    ('uint16', 'uint16'),
    ('uint32', 'uint32'),
    ('uint64', 'uint64'),
    ('float64', 'float16'),
    ('float64', 'float32'),
    ('float64', 'float64'),
    ('date', 'datetime64[ns]'),
    ('tz_aware_dates', 'datetime64[ns, US/Eastern]'),
    ('string', 'object(string)'),
    ('decimal', 'object(Decimal)'),
    ('array', 'object(array[int32])'),
    ('float128', 'float128'),
    ('complex64', 'complex64'),
    ('complex128', 'complex128'),
    ('category', 'category'),
    ('tdeltas', 'timedelta64[ns]'),
]

def create_dataframe():
    import pandas as pd
    import numpy as np
    import decimal
    pdf = pd.DataFrame({
        'none': [None, None],
        'bool': [True, False],
        'int8': np.arange(1, 3).astype('int8'),
        'int16': np.arange(1, 3).astype('int16'),
        'int32': np.arange(1, 3).astype('int32'),
        'int64': np.arange(1, 3).astype('int64'),
        'uint8': np.arange(1, 3).astype('uint8'),
        'uint16': np.arange(1, 3).astype('uint16'),
        'uint32': np.arange(1, 3).astype('uint32'),
        'uint64': np.arange(1, 3).astype('uint64'),
        'float16': np.arange(1, 3).astype('float16'),
        'float32': np.arange(1, 3).astype('float32'),
        'float64': np.arange(1, 3).astype('float64'),
        'float128': np.arange(1, 3).astype('float128'),
        'complex64': np.arange(1, 3).astype('complex64'),
        'complex128': np.arange(1, 3).astype('complex128'),
        'string': list('ab'),
        'array': pd.Series([np.array([1, 2, 3], dtype=np.int32), np.array([1, 2, 3], dtype=np.int32)]),
        'decimal': pd.Series([decimal.Decimal('1'), decimal.Decimal('2')]),
        'date': pd.date_range('19700101', periods=2).values,
        'category': pd.Series(list("AB")).astype('category')})
    pdf['tdeltas'] = [pdf.date.diff()[1], pdf.date.diff()[0]]
    pdf['tz_aware_dates'] = pd.date_range('19700101', periods=2, tz='US/Eastern')
    return pdf

types =  [
    BooleanType(),
    ByteType(),
    ShortType(),
    IntegerType(),
    LongType(),
    FloatType(),
    DoubleType(),
    DateType(),
    TimestampType(),
    StringType(),
    DecimalType(10, 0),
    ArrayType(IntegerType()),
    MapType(StringType(), IntegerType()),
    StructType([StructField("_1", IntegerType())]),
    BinaryType(),
]

df = spark.range(2).repartition(1)
results = []
count = 0
total = len(types) * len(columns)
values = []
spark.sparkContext.setLogLevel("FATAL")
for t in types:
    result = []
    for column, pandas_t in columns:
        v = create_dataframe()[column][0]
        values.append(v)
        try:
            row = df.select(pandas_udf(lambda _: create_dataframe()[column], t)(df.id)).first()
            ret_str = repr(row[0])
        except Exception:
            ret_str = "X"
        result.append(ret_str)
        progress = "SQL Type: [%s]\n  Pandas Value(Type): %s(%s)]\n  Result Python Value: [%s]" % (
            t.simpleString(), v, pandas_t, ret_str)
        count += 1
        print("%s/%s:\n  %s" % (count, total, progress))
    results.append([t.simpleString()] + list(map(str, result)))

schema = ["SQL Type \\ Pandas Value(Type)"] + list(map(lambda values_column: "%s(%s)" % (values_column[0], values_column[1][1]), zip(values, columns)))
strings = spark.createDataFrame(results, schema=schema)._jdf.showString(20, 20, False)
print("\n".join(map(lambda line: "    # %s  # noqa" % line, strings.strip().split("\n"))))
```

## How was this patch tested?

Manually.

Closes #24930 from HyukjinKwon/SPARK-28132.

Authored-by: HyukjinKwon <gurwls223@apache.org>
Signed-off-by: Bryan Cutler <cutlerb@gmail.com>
2019-06-21 10:47:54 -07:00
HyukjinKwon 9b9d81b821 [SPARK-28131][PYTHON] Update document type conversion between Python data and SQL types in normal UDFs (Python 3.7)
## What changes were proposed in this pull request?

This PR updates the chart generated at SPARK-25666. We deprecated Python 2. It's better to use Python 3.

We don't have to test `unicode` and `long` anymore in Python 3. So it was removed.

Use this code to generate the chart:

```python
import sys
import array
import datetime
from decimal import Decimal

from pyspark.sql import Row
from pyspark.sql.types import *
from pyspark.sql.functions import udf

data = [
    None,
    True,
    1,
    "a",
    datetime.date(1970, 1, 1),
    datetime.datetime(1970, 1, 1, 0, 0),
    1.0,
    array.array("i", [1]),
    [1],
    (1,),
    bytearray([65, 66, 67]),
    Decimal(1),
    {"a": 1},
    Row(kwargs=1),
    Row("namedtuple")(1),
]

types =  [
    BooleanType(),
    ByteType(),
    ShortType(),
    IntegerType(),
    LongType(),
    StringType(),
    DateType(),
    TimestampType(),
    FloatType(),
    DoubleType(),
    ArrayType(IntegerType()),
    BinaryType(),
    DecimalType(10, 0),
    MapType(StringType(), IntegerType()),
    StructType([StructField("_1", IntegerType())]),
]

df = spark.range(1)
results = []
count = 0
total = len(types) * len(data)
spark.sparkContext.setLogLevel("FATAL")
for t in types:
    result = []
    for v in data:
        try:
            row = df.select(udf(lambda: v, t)()).first()
            ret_str = repr(row[0])
        except Exception:
            ret_str = "X"
        result.append(ret_str)
        progress = "SQL Type: [%s]\n  Python Value: [%s(%s)]\n  Result Python Value: [%s]" % (
            t.simpleString(), str(v), type(v).__name__, ret_str)
        count += 1
        print("%s/%s:\n  %s" % (count, total, progress))
    results.append([t.simpleString()] + list(map(str, result)))

schema = ["SQL Type \\ Python Value(Type)"] + list(map(lambda v: "%s(%s)" % (str(v), type(v).__name__), data))
strings = spark.createDataFrame(results, schema=schema)._jdf.showString(20, 20, False)
print("\n".join(map(lambda line: "    # %s  # noqa" % line, strings.strip().split("\n"))))
```

## How was this patch tested?

Manually.

Closes #24929 from HyukjinKwon/SPARK-28131.

Lead-authored-by: HyukjinKwon <gurwls223@apache.org>
Co-authored-by: Hyukjin Kwon <gurwls223@apache.org>
Signed-off-by: Bryan Cutler <cutlerb@gmail.com>
2019-06-21 10:27:18 -07:00
tools4origins 25c5d57883 [MINOR][DOC] Fix python variance() documentation
## What changes were proposed in this pull request?

The Python documentation incorrectly says that `variance()` acts as `var_pop` whereas it acts like `var_samp` here: https://spark.apache.org/docs/latest/api/python/pyspark.sql.html#pyspark.sql.functions.variance

It was not the case in Spark 1.6 doc but it is in Spark 2.0 doc:
https://spark.apache.org/docs/1.6.0/api/java/org/apache/spark/sql/functions.html
https://spark.apache.org/docs/2.0.0/api/java/org/apache/spark/sql/functions.html

The Scala documentation is correct: https://spark.apache.org/docs/latest/api/java/org/apache/spark/sql/functions.html#variance-org.apache.spark.sql.Column-

The alias is set on this line:
https://github.com/apache/spark/blob/v2.4.3/sql/core/src/main/scala/org/apache/spark/sql/functions.scala#L786

## How was this patch tested?
Using variance() in pyspark 2.4.3 returns:
```
>>> spark.createDataFrame([(1, ), (2, ), (3, )], "a: int").select(variance("a")).show()
+-----------+
|var_samp(a)|
+-----------+
|        1.0|
+-----------+
```

Closes #24895 from tools4origins/patch-1.

Authored-by: tools4origins <tools4origins@gmail.com>
Signed-off-by: Dongjoon Hyun <dhyun@apple.com>
2019-06-20 08:10:19 -07:00
WeichenXu 6d441dcdc6 [SPARK-26412][PYSPARK][SQL] Allow Pandas UDF to take an iterator of pd.Series or an iterator of tuple of pd.Series
## What changes were proposed in this pull request?

Allow Pandas UDF to take an iterator of pd.Series or an iterator of tuple of pd.Series.
Note the UDF input args will be always one iterator:
* if the udf take only column as input, the iterator's element will be pd.Series (corresponding to the column values batch)
* if the udf take multiple columns as inputs, the iterator's element will be a tuple composed of multiple `pd.Series`s, each one corresponding to the multiple columns as inputs (keep the same order). For example:
```
pandas_udf("int", PandasUDFType.SCALAR_ITER)
def the_udf(iterator):
    for col1_batch, col2_batch in iterator:
        yield col1_batch + col2_batch

df.select(the_udf("col1", "col2"))
```
The udf above will add col1 and col2.

I haven't add unit tests, but manually tests show it works fine. So it is ready for first pass review.
We can test several typical cases:

```
from pyspark.sql import SparkSession
from pyspark.sql.functions import pandas_udf, PandasUDFType
from pyspark.sql.functions import udf
from pyspark.taskcontext import TaskContext

df = spark.createDataFrame([(1, 20), (3, 40)], ["a", "b"])

pandas_udf("int", PandasUDFType.SCALAR_ITER)
def fi1(it):
    pid = TaskContext.get().partitionId()
    print("DBG: fi1: do init stuff, partitionId=" + str(pid))
    for batch in it:
        yield batch + 100
    print("DBG: fi1: do close stuff, partitionId=" + str(pid))

pandas_udf("int", PandasUDFType.SCALAR_ITER)
def fi2(it):
    pid = TaskContext.get().partitionId()
    print("DBG: fi2: do init stuff, partitionId=" + str(pid))
    for batch in it:
        yield batch + 10000
    print("DBG: fi2: do close stuff, partitionId=" + str(pid))

pandas_udf("int", PandasUDFType.SCALAR_ITER)
def fi3(it):
    pid = TaskContext.get().partitionId()
    print("DBG: fi3: do init stuff, partitionId=" + str(pid))
    for x, y in it:
        yield x + y * 10 + 100000
    print("DBG: fi3: do close stuff, partitionId=" + str(pid))

pandas_udf("int", PandasUDFType.SCALAR)
def fp1(x):
    return x + 1000

udf("int")
def fu1(x):
    return x + 10

# test select "pandas iter udf/pandas udf/sql udf" expressions at the same time.
# Note this case the `fi1("a"), fi2("b"), fi3("a", "b")` will generate only one plan,
# and `fu1("a")`, `fp1("a")` will generate another two separate plans.
df.select(fi1("a"), fi2("b"), fi3("a", "b"), fu1("a"), fp1("a")).show()

# test chain two pandas iter udf together
# Note this case `fi2(fi1("a"))` will generate only one plan
# Also note the init stuff/close stuff call order will be like:
# (debug output following)
#     DBG: fi2: do init stuff, partitionId=0
#     DBG: fi1: do init stuff, partitionId=0
#     DBG: fi1: do close stuff, partitionId=0
#     DBG: fi2: do close stuff, partitionId=0
df.select(fi2(fi1("a"))).show()

# test more complex chain
# Note this case `fi1("a"), fi2("a")` will generate one plan,
# and `fi3(fi1_output, fi2_output)` will generate another plan
df.select(fi3(fi1("a"), fi2("a"))).show()
```

## How was this patch tested?

To be added.

Please review http://spark.apache.org/contributing.html before opening a pull request.

Closes #24643 from WeichenXu123/pandas_udf_iter.

Lead-authored-by: WeichenXu <weichen.xu@databricks.com>
Co-authored-by: Xiangrui Meng <meng@databricks.com>
Signed-off-by: Xiangrui Meng <meng@databricks.com>
2019-06-15 08:29:20 -07:00
Jash Gala 90085a1847 [SPARK-23619][DOCS] Add output description for some generator expressions / functions
## What changes were proposed in this pull request?

This PR addresses SPARK-23619: https://issues.apache.org/jira/browse/SPARK-23619

It adds additional comments indicating the default column names for the `explode` and `posexplode`
functions in Spark-SQL.

Functions for which comments have been updated so far:
* stack
* inline
* explode
* posexplode
* explode_outer
* posexplode_outer

## How was this patch tested?

This is just a change in the comments. The package builds and tests successfullly after the change.

Closes #23748 from jashgala/SPARK-23619.

Authored-by: Jash Gala <jashgala@amazon.com>
Signed-off-by: HyukjinKwon <gurwls223@apache.org>
2019-04-27 10:30:12 +09:00
Maxim Gekk 1d20d13149 [SPARK-25496][SQL] Deprecate from_utc_timestamp and to_utc_timestamp
## What changes were proposed in this pull request?

In the PR, I propose to deprecate the `from_utc_timestamp()` and `to_utc_timestamp`, and disable them by default. The functions can be enabled back via the SQL config `spark.sql.legacy.utcTimestampFunc.enabled`. By default, any calls of the functions throw an analysis exception.

One of the reason for deprecation is functions violate semantic of `TimestampType` which is number of microseconds since epoch in UTC time zone. Shifting microseconds since epoch by time zone offset doesn't make sense because the result doesn't represent microseconds since epoch in UTC time zone any more, and cannot be considered as `TimestampType`.

## How was this patch tested?

The changes were tested by `DateExpressionsSuite` and `DateFunctionsSuite`.

Closes #24195 from MaxGekk/conv-utc-timestamp-deprecate.

Lead-authored-by: Maxim Gekk <max.gekk@gmail.com>
Co-authored-by: Maxim Gekk <maxim.gekk@databricks.com>
Co-authored-by: Hyukjin Kwon <gurwls223@apache.org>
Signed-off-by: Wenchen Fan <wenchen@databricks.com>
2019-04-03 10:55:56 +08:00
Dongjoon Hyun d575a453db Revert "[SPARK-25496][SQL] Deprecate from_utc_timestamp and to_utc_timestamp"
This reverts commit c5e83ab92c.
2019-04-02 01:05:54 -07:00
Maxim Gekk c5e83ab92c [SPARK-25496][SQL] Deprecate from_utc_timestamp and to_utc_timestamp
## What changes were proposed in this pull request?

In the PR, I propose to deprecate the `from_utc_timestamp()` and `to_utc_timestamp`, and disable them by default. The functions can be enabled back via the SQL config `spark.sql.legacy.utcTimestampFunc.enabled`. By default, any calls of the functions throw an analysis exception.

One of the reason for deprecation is functions violate semantic of `TimestampType` which is number of microseconds since epoch in UTC time zone. Shifting microseconds since epoch by time zone offset doesn't make sense because the result doesn't represent microseconds since epoch in UTC time zone any more, and cannot be considered as `TimestampType`.

## How was this patch tested?

The changes were tested by `DateExpressionsSuite` and `DateFunctionsSuite`.

Closes #24195 from MaxGekk/conv-utc-timestamp-deprecate.

Lead-authored-by: Maxim Gekk <max.gekk@gmail.com>
Co-authored-by: Maxim Gekk <maxim.gekk@databricks.com>
Co-authored-by: Hyukjin Kwon <gurwls223@apache.org>
Signed-off-by: Wenchen Fan <wenchen@databricks.com>
2019-04-02 10:20:06 +08:00
Maxim Gekk 027ed2d11b [SPARK-23643][CORE][SQL][ML] Shrinking the buffer in hashSeed up to size of the seed parameter
## What changes were proposed in this pull request?

The hashSeed method allocates 64 bytes instead of 8. Other bytes are always zeros (thanks to default behavior of ByteBuffer). And they could be excluded from hash calculation because they don't differentiate inputs.

## How was this patch tested?

By running the existing tests - XORShiftRandomSuite

Closes #20793 from MaxGekk/hash-buff-size.

Lead-authored-by: Maxim Gekk <maxim.gekk@databricks.com>
Co-authored-by: Maxim Gekk <max.gekk@gmail.com>
Signed-off-by: Sean Owen <sean.owen@databricks.com>
2019-03-23 11:26:09 -05:00
Huon Wilson b67d369572 [SPARK-27099][SQL] Add 'xxhash64' for hashing arbitrary columns to Long
## What changes were proposed in this pull request?

This introduces a new SQL function 'xxhash64' for getting a 64-bit hash of an arbitrary number of columns.

This is designed to exactly mimic the 32-bit `hash`, which uses
MurmurHash3. The name is designed to be more future-proof than the
'hash', by indicating the exact algorithm used, similar to md5 and the
sha hashes.

## How was this patch tested?

The tests for the existing `hash` function were duplicated to run with `xxhash64`.

Closes #24019 from huonw/hash64.

Authored-by: Huon Wilson <Huon.Wilson@data61.csiro.au>
Signed-off-by: Wenchen Fan <wenchen@databricks.com>
2019-03-20 16:34:34 +08:00
Hyukjin Kwon c99463d4cf [SPARK-26979][PYTHON][FOLLOW-UP] Make binary math/string functions take string as columns as well
## What changes were proposed in this pull request?

This is a followup of https://github.com/apache/spark/pull/23882 to handle binary math/string functions. For instance, see the cases below:

**Before:**

```python
>>> from pyspark.sql.functions import lit, ascii
>>> spark.range(1).select(lit('a').alias("value")).select(ascii("value"))
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "/.../spark/python/pyspark/sql/functions.py", line 51, in _
    jc = getattr(sc._jvm.functions, name)(col._jc if isinstance(col, Column) else col)
  File "/.../spark/python/lib/py4j-0.10.8.1-src.zip/py4j/java_gateway.py", line 1286, in __call__
  File "/.../spark/python/pyspark/sql/utils.py", line 63, in deco
    return f(*a, **kw)
  File "/.../spark/python/lib/py4j-0.10.8.1-src.zip/py4j/protocol.py", line 332, in get_return_value
py4j.protocol.Py4JError: An error occurred while calling z:org.apache.spark.sql.functions.ascii. Trace:
py4j.Py4JException: Method ascii([class java.lang.String]) does not exist
	at py4j.reflection.ReflectionEngine.getMethod(ReflectionEngine.java:318)
	at py4j.reflection.ReflectionEngine.getMethod(ReflectionEngine.java:339)
	at py4j.Gateway.invoke(Gateway.java:276)
	at py4j.commands.AbstractCommand.invokeMethod(AbstractCommand.java:132)
	at py4j.commands.CallCommand.execute(CallCommand.java:79)
	at py4j.GatewayConnection.run(GatewayConnection.java:238)
	at java.lang.Thread.run(Thread.java:748)
```

```python
>>> from pyspark.sql.functions import atan2
>>> spark.range(1).select(atan2("id", "id"))
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "/.../spark/python/pyspark/sql/functions.py", line 78, in _
    jc = getattr(sc._jvm.functions, name)(col1._jc if isinstance(col1, Column) else float(col1),
ValueError: could not convert string to float: id
```

**After:**

```python
>>> from pyspark.sql.functions import lit, ascii
>>> spark.range(1).select(lit('a').alias("value")).select(ascii("value"))
DataFrame[ascii(value): int]
```

```python
>>> from pyspark.sql.functions import atan2
>>> spark.range(1).select(atan2("id", "id"))
DataFrame[ATAN2(id, id): double]
```

Note that,

- This PR causes a slight behaviour changes for math functions. For instance, numbers as strings (e.g., `"1"`) were supported as arguments of binary math functions before. After this PR, it recognises it as column names.

- I also intentionally didn't document this behaviour changes since we're going ahead for Spark 3.0 and I don't think numbers as strings make much sense in math functions.

- There is another exception `when`, which takes string as literal values as below. This PR doeesn't fix this ambiguity.
  ```python
  >>> spark.range(1).select(when(lit(True), col("id"))).show()
  ```

  ```
  +--------------------------+
  |CASE WHEN true THEN id END|
  +--------------------------+
  |                         0|
  +--------------------------+
  ```

  ```python
  >>> spark.range(1).select(when(lit(True), "id")).show()
  ```

  ```
  +--------------------------+
  |CASE WHEN true THEN id END|
  +--------------------------+
  |                        id|
  +--------------------------+
  ```

This PR also fixes as below:

https://github.com/apache/spark/pull/23882 fixed it to:

- Rename `_create_function` to `_create_name_function`
- Define new `_create_function` to take strings as column names.

This PR, I proposes to:

- Revert `_create_name_function` name to `_create_function`.
- Define new `_create_function_over_column` to take strings as column names.

## How was this patch tested?

Some unit tests were added for binary math / string functions.

Closes #24121 from HyukjinKwon/SPARK-26979.

Authored-by: Hyukjin Kwon <gurwls223@apache.org>
Signed-off-by: Hyukjin Kwon <gurwls223@apache.org>
2019-03-20 08:06:10 +09:00
André Sá de Mello f9180f8752 [SPARK-26979][PYTHON] Add missing string column name support for some SQL functions
## What changes were proposed in this pull request?

Most SQL functions defined in `spark.sql.functions` have two calling patterns, one with a Column object as input, and another with a string representing a column name, which is then converted into a Column object internally.

There are, however, a few notable exceptions:

- lower()
- upper()
- abs()
- bitwiseNOT()
- ltrim()
- rtrim()
- trim()
- ascii()
- base64()
- unbase64()

While this doesn't break anything, as you can easily create a Column object yourself prior to passing it to one of these functions, it has two undesirable consequences:

1. It is surprising - it breaks coder's expectations when they are first starting with Spark. Every API should be as consistent as possible, so as to make the learning curve smoother and to reduce causes for human error;

2. It gets in the way of stylistic conventions. Most of the time it makes Python code more readable to use literal names, and the API provides ample support for that, but these few exceptions prevent this pattern from being universally applicable.

This patch is meant to fix the aforementioned problem.

### Effect

This patch **enables** support for passing column names as input to those functions mentioned above.

### Side effects

This PR also **fixes** an issue with some functions being defined multiple times by using `_create_function()`.

### How it works

`_create_function()` was redefined to always convert the argument to a Column object. The old implementation has been kept under `_create_name_function()`, and is still being used to generate the following special functions:

- lit()
- col()
- column()
- asc()
- desc()
- asc_nulls_first()
- asc_nulls_last()
- desc_nulls_first()
- desc_nulls_last()

This is because these functions can only take a column name as their argument. This is not a problem, as their semantics require so.

## How was this patch tested?

Ran ./dev/run-tests and tested it manually.

Closes #23882 from asmello/col-name-support-pyspark.

Authored-by: André Sá de Mello <amello@palantir.com>
Signed-off-by: Sean Owen <sean.owen@databricks.com>
2019-03-17 12:58:16 -05:00
Bryan Cutler ddc2052ebd [SPARK-23836][PYTHON] Add support for StructType return in Scalar Pandas UDF
## What changes were proposed in this pull request?

This change adds support for returning StructType from a scalar Pandas UDF, where the return value of the function is a pandas.DataFrame. Nested structs are not supported and an error will be raised, child types can be any other type currently supported.

## How was this patch tested?

Added additional unit tests to `test_pandas_udf_scalar`

Closes #23900 from BryanCutler/pyspark-support-scalar_udf-StructType-SPARK-23836.

Authored-by: Bryan Cutler <cutlerb@gmail.com>
Signed-off-by: Bryan Cutler <cutlerb@gmail.com>
2019-03-07 08:52:24 -08:00