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https://issues.apache.org/jira/browse/BEAM-7389?focusedWorklogId=293372&page=com.atlassian.jira.plugin.system.issuetabpanels:worklog-tabpanel#worklog-293372
]
ASF GitHub Bot logged work on BEAM-7389:
----------------------------------------
Author: ASF GitHub Bot
Created on: 12/Aug/19 20:44
Start Date: 12/Aug/19 20:44
Worklog Time Spent: 10m
Work Description: rosetn commented on pull request #9260: [BEAM-7389] Add
code examples for FlatMap page
URL: https://github.com/apache/beam/pull/9260#discussion_r313119708
##########
File path: website/src/documentation/transforms/python/element-wise/flatmap.md
##########
@@ -19,24 +19,287 @@ limitations under the License.
-->
# FlatMap
-<table align="left">
- <a target="_blank" class="button"
+
+<script type="text/javascript">
+localStorage.setItem('language', 'language-py')
+</script>
+
+<table>
+ <td>
+ <a class="button" target="_blank"
href="https://beam.apache.org/releases/pydoc/current/apache_beam.transforms.core.html#apache_beam.transforms.core.FlatMap";>
- <img src="https://beam.apache.org/images/logos/sdks/python.png";
width="20px" height="20px"
- alt="Pydoc" />
- Pydoc
+ <img src="https://beam.apache.org/images/logos/sdks/python.png";
+ width="20px" height="20px" alt="Pydoc" />
+ Pydoc
</a>
+ </td>
</table>
<br>
+
Applies a simple 1-to-many mapping function over each element in the
collection.
The many elements are flattened into the resulting collection.
## Examples
-See [BEAM-7389](https://issues.apache.org/jira/browse/BEAM-7389) for updates.
-## Related transforms
+In the following examples, we create a pipeline with a `PCollection` of
produce their icon, name, and duration.
+Then, we apply `FlatMap` in multiple ways to yield zero or more elements per
each input element into the resulting `PCollection`.
+
+`FlatMap` accepts a function that returns an `iterable`,
+where each of the output `iterable`'s elements is an element of the resulting
`PCollection`.
+
+### Example 1: FlatMap with a predefined function
+
+We use the function `str.split` which takes a single `str` element and outputs
a `list` of `str`s.
+This pipeline splits the input element using whitespaces, creating a list of
zero or more elements.
+
+```py
+{% github_sample
/apache/beam/blob/master/sdks/python/apache_beam/examples/snippets/transforms/element_wise/flat_map.py
tag:flat_map_simple %}```
+
+Output `PCollection` after `FlatMap`:
+
+```
+{% github_sample
/apache/beam/blob/master/sdks/python/apache_beam/examples/snippets/transforms/element_wise/flat_map_test.py
tag:plants %}```
+
+<table>
+ <td>
+ <a class="button" target="_blank"
+
href="https://github.com/apache/beam/blob/master/sdks/python/apache_beam/examples/snippets/transforms/element_wise/flat_map.py";>
+ <img src="https://www.tensorflow.org/images/GitHub-Mark-32px.png";
+ width="20px" height="20px" alt="View on GitHub" />
+ View on GitHub
+ </a>
+ </td>
+</table>
+<br>
+
+### Example 2: FlatMap with a function
+
+We define a function `split_words` which splits an input `str` element using
the delimiter `','` and outputs a `list` of `str`s.
+
+```py
+{% github_sample
/apache/beam/blob/master/sdks/python/apache_beam/examples/snippets/transforms/element_wise/flat_map.py
tag:flat_map_function %}```
+
+Output `PCollection` after `FlatMap`:
+
+```
+{% github_sample
/apache/beam/blob/master/sdks/python/apache_beam/examples/snippets/transforms/element_wise/flat_map_test.py
tag:plants %}```
+
+<table>
+ <td>
+ <a class="button" target="_blank"
+
href="https://github.com/apache/beam/blob/master/sdks/python/apache_beam/examples/snippets/transforms/element_wise/flat_map.py";>
+ <img src="https://www.tensorflow.org/images/GitHub-Mark-32px.png";
+ width="20px" height="20px" alt="View on GitHub" />
+ View on GitHub
+ </a>
+ </td>
+</table>
+<br>
+
+### Example 3: FlatMap with a lambda function
+
+For this example, we want to flatten a `PCollection` of lists of `str`s into a
`PCollection` of `str`s.
+Each input element is already an `iterable`, where each element is what we
want in the resulting `PCollection`.
+We use a lambda function that returns the same input element it received.
+
+```py
+{% github_sample
/apache/beam/blob/master/sdks/python/apache_beam/examples/snippets/transforms/element_wise/flat_map.py
tag:flat_map_lambda %}```
+
+Output `PCollection` after `FlatMap`:
+
+```
+{% github_sample
/apache/beam/blob/master/sdks/python/apache_beam/examples/snippets/transforms/element_wise/flat_map_test.py
tag:plants %}```
+
+<table>
+ <td>
+ <a class="button" target="_blank"
+
href="https://github.com/apache/beam/blob/master/sdks/python/apache_beam/examples/snippets/transforms/element_wise/flat_map.py";>
+ <img src="https://www.tensorflow.org/images/GitHub-Mark-32px.png";
+ width="20px" height="20px" alt="View on GitHub" />
+ View on GitHub
+ </a>
+ </td>
+</table>
+<br>
+
+### Example 4: FlatMap with a generator
+
+For this example, we want to flatten a `PCollection` of lists of `str`s into a
`PCollection` of `str`s.
+We use a generator to iterate over the input list and yield each of the
elements.
+Each yielded result in the generator will be an element in the resulting
`PCollection`.
Review comment:
Missed this "will be"->"is"
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Issue Time Tracking
-------------------
Worklog Id: (was: 293372)
Time Spent: 40h 10m (was: 40h)
> Colab examples for element-wise transforms (Python)
> ---------------------------------------------------
>
> Key: BEAM-7389
> URL: https://issues.apache.org/jira/browse/BEAM-7389
> Project: Beam
> Issue Type: Improvement
> Components: website
> Reporter: Rose Nguyen
> Assignee: David Cavazos
> Priority: Minor
> Time Spent: 40h 10m
> Remaining Estimate: 0h
>
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