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| <ul class="summary"> |
| <li class="chapter" data-level="1" data-path="index.html"><a href="index.html"><i class="fa fa-check"></i><b>1</b> Preface</a> |
| <ul> |
| <li class="chapter" data-level="1.1" data-path="index.html"><a href="index.html#what-is-arrow"><i class="fa fa-check"></i><b>1.1</b> What is Arrow?</a></li> |
| <li class="chapter" data-level="1.2" data-path="index.html"><a href="index.html#alternative-resources"><i class="fa fa-check"></i><b>1.2</b> Alternative resources</a></li> |
| </ul></li> |
| <li class="chapter" data-level="2" data-path="reading-and-writing-data---single-files.html"><a href="reading-and-writing-data---single-files.html"><i class="fa fa-check"></i><b>2</b> Reading and Writing Data - Single Files</a> |
| <ul> |
| <li class="chapter" data-level="2.1" data-path="reading-and-writing-data---single-files.html"><a href="reading-and-writing-data---single-files.html#introduction"><i class="fa fa-check"></i><b>2.1</b> Introduction</a></li> |
| <li class="chapter" data-level="2.2" data-path="reading-and-writing-data---single-files.html"><a href="reading-and-writing-data---single-files.html#convert-data-from-a-data-frame-to-an-arrow-table"><i class="fa fa-check"></i><b>2.2</b> Convert data from a data frame to an Arrow Table</a> |
| <ul> |
| <li class="chapter" data-level="2.2.1" data-path="reading-and-writing-data---single-files.html"><a href="reading-and-writing-data---single-files.html#solution"><i class="fa fa-check"></i><b>2.2.1</b> Solution</a></li> |
| </ul></li> |
| <li class="chapter" data-level="2.3" data-path="reading-and-writing-data---single-files.html"><a href="reading-and-writing-data---single-files.html#convert-data-from-an-arrow-table-to-a-data-frame"><i class="fa fa-check"></i><b>2.3</b> Convert data from an Arrow Table to a data frame</a> |
| <ul> |
| <li class="chapter" data-level="2.3.1" data-path="reading-and-writing-data---single-files.html"><a href="reading-and-writing-data---single-files.html#solution-1"><i class="fa fa-check"></i><b>2.3.1</b> Solution</a></li> |
| <li class="chapter" data-level="2.3.2" data-path="reading-and-writing-data---single-files.html"><a href="reading-and-writing-data---single-files.html#discussion"><i class="fa fa-check"></i><b>2.3.2</b> Discussion</a></li> |
| </ul></li> |
| <li class="chapter" data-level="2.4" data-path="reading-and-writing-data---single-files.html"><a href="reading-and-writing-data---single-files.html#write-a-parquet-file"><i class="fa fa-check"></i><b>2.4</b> Write a Parquet file</a> |
| <ul> |
| <li class="chapter" data-level="2.4.1" data-path="reading-and-writing-data---single-files.html"><a href="reading-and-writing-data---single-files.html#solution-2"><i class="fa fa-check"></i><b>2.4.1</b> Solution</a></li> |
| </ul></li> |
| <li class="chapter" data-level="2.5" data-path="reading-and-writing-data---single-files.html"><a href="reading-and-writing-data---single-files.html#read-a-parquet-file"><i class="fa fa-check"></i><b>2.5</b> Read a Parquet file</a> |
| <ul> |
| <li class="chapter" data-level="2.5.1" data-path="reading-and-writing-data---single-files.html"><a href="reading-and-writing-data---single-files.html#solution-3"><i class="fa fa-check"></i><b>2.5.1</b> Solution</a></li> |
| <li class="chapter" data-level="2.5.2" data-path="reading-and-writing-data---single-files.html"><a href="reading-and-writing-data---single-files.html#discussion-1"><i class="fa fa-check"></i><b>2.5.2</b> Discussion</a></li> |
| </ul></li> |
| <li class="chapter" data-level="2.6" data-path="reading-and-writing-data---single-files.html"><a href="reading-and-writing-data---single-files.html#read-a-parquet-file-from-s3"><i class="fa fa-check"></i><b>2.6</b> Read a Parquet file from S3</a> |
| <ul> |
| <li class="chapter" data-level="2.6.1" data-path="reading-and-writing-data---single-files.html"><a href="reading-and-writing-data---single-files.html#solution-4"><i class="fa fa-check"></i><b>2.6.1</b> Solution</a></li> |
| <li class="chapter" data-level="2.6.2" data-path="reading-and-writing-data---single-files.html"><a href="reading-and-writing-data---single-files.html#see-also"><i class="fa fa-check"></i><b>2.6.2</b> See also</a></li> |
| </ul></li> |
| <li class="chapter" data-level="2.7" data-path="reading-and-writing-data---single-files.html"><a href="reading-and-writing-data---single-files.html#filter-columns-while-reading-a-parquet-file"><i class="fa fa-check"></i><b>2.7</b> Filter columns while reading a Parquet file</a> |
| <ul> |
| <li class="chapter" data-level="2.7.1" data-path="reading-and-writing-data---single-files.html"><a href="reading-and-writing-data---single-files.html#solution-5"><i class="fa fa-check"></i><b>2.7.1</b> Solution</a></li> |
| </ul></li> |
| <li class="chapter" data-level="2.8" data-path="reading-and-writing-data---single-files.html"><a href="reading-and-writing-data---single-files.html#write-a-feather-v2arrow-ipc-file"><i class="fa fa-check"></i><b>2.8</b> Write a Feather V2/Arrow IPC file</a> |
| <ul> |
| <li class="chapter" data-level="2.8.1" data-path="reading-and-writing-data---single-files.html"><a href="reading-and-writing-data---single-files.html#solution-6"><i class="fa fa-check"></i><b>2.8.1</b> Solution</a></li> |
| <li class="chapter" data-level="2.8.2" data-path="reading-and-writing-data---single-files.html"><a href="reading-and-writing-data---single-files.html#discussion-2"><i class="fa fa-check"></i><b>2.8.2</b> Discussion</a></li> |
| </ul></li> |
| <li class="chapter" data-level="2.9" data-path="reading-and-writing-data---single-files.html"><a href="reading-and-writing-data---single-files.html#read-a-featherarrow-ipc-file"><i class="fa fa-check"></i><b>2.9</b> Read a Feather/Arrow IPC file</a> |
| <ul> |
| <li class="chapter" data-level="2.9.1" data-path="reading-and-writing-data---single-files.html"><a href="reading-and-writing-data---single-files.html#solution-7"><i class="fa fa-check"></i><b>2.9.1</b> Solution</a></li> |
| </ul></li> |
| <li class="chapter" data-level="2.10" data-path="reading-and-writing-data---single-files.html"><a href="reading-and-writing-data---single-files.html#write-streaming-arrow-ipc-files"><i class="fa fa-check"></i><b>2.10</b> Write streaming Arrow IPC files</a> |
| <ul> |
| <li class="chapter" data-level="2.10.1" data-path="reading-and-writing-data---single-files.html"><a href="reading-and-writing-data---single-files.html#solution-8"><i class="fa fa-check"></i><b>2.10.1</b> Solution</a></li> |
| </ul></li> |
| <li class="chapter" data-level="2.11" data-path="reading-and-writing-data---single-files.html"><a href="reading-and-writing-data---single-files.html#read-streaming-arrow-ipc-files"><i class="fa fa-check"></i><b>2.11</b> Read streaming Arrow IPC files</a> |
| <ul> |
| <li class="chapter" data-level="2.11.1" data-path="reading-and-writing-data---single-files.html"><a href="reading-and-writing-data---single-files.html#solution-9"><i class="fa fa-check"></i><b>2.11.1</b> Solution</a></li> |
| </ul></li> |
| <li class="chapter" data-level="2.12" data-path="reading-and-writing-data---single-files.html"><a href="reading-and-writing-data---single-files.html#write-a-csv-file"><i class="fa fa-check"></i><b>2.12</b> Write a CSV file</a> |
| <ul> |
| <li class="chapter" data-level="2.12.1" data-path="reading-and-writing-data---single-files.html"><a href="reading-and-writing-data---single-files.html#solution-10"><i class="fa fa-check"></i><b>2.12.1</b> Solution</a></li> |
| </ul></li> |
| <li class="chapter" data-level="2.13" data-path="reading-and-writing-data---single-files.html"><a href="reading-and-writing-data---single-files.html#read-a-csv-file"><i class="fa fa-check"></i><b>2.13</b> Read a CSV file</a> |
| <ul> |
| <li class="chapter" data-level="2.13.1" data-path="reading-and-writing-data---single-files.html"><a href="reading-and-writing-data---single-files.html#solution-11"><i class="fa fa-check"></i><b>2.13.1</b> Solution</a></li> |
| </ul></li> |
| <li class="chapter" data-level="2.14" data-path="reading-and-writing-data---single-files.html"><a href="reading-and-writing-data---single-files.html#read-a-json-file"><i class="fa fa-check"></i><b>2.14</b> Read a JSON file</a> |
| <ul> |
| <li class="chapter" data-level="2.14.1" data-path="reading-and-writing-data---single-files.html"><a href="reading-and-writing-data---single-files.html#solution-12"><i class="fa fa-check"></i><b>2.14.1</b> Solution</a></li> |
| </ul></li> |
| <li class="chapter" data-level="2.15" data-path="reading-and-writing-data---single-files.html"><a href="reading-and-writing-data---single-files.html#write-a-compressed-single-data-file"><i class="fa fa-check"></i><b>2.15</b> Write a compressed single data file</a> |
| <ul> |
| <li class="chapter" data-level="2.15.1" data-path="reading-and-writing-data---single-files.html"><a href="reading-and-writing-data---single-files.html#solution-13"><i class="fa fa-check"></i><b>2.15.1</b> Solution</a></li> |
| <li class="chapter" data-level="2.15.2" data-path="reading-and-writing-data---single-files.html"><a href="reading-and-writing-data---single-files.html#see-also-1"><i class="fa fa-check"></i><b>2.15.2</b> See also</a></li> |
| </ul></li> |
| <li class="chapter" data-level="2.16" data-path="reading-and-writing-data---single-files.html"><a href="reading-and-writing-data---single-files.html#read-compressed-data"><i class="fa fa-check"></i><b>2.16</b> Read compressed data</a> |
| <ul> |
| <li class="chapter" data-level="2.16.1" data-path="reading-and-writing-data---single-files.html"><a href="reading-and-writing-data---single-files.html#solution-14"><i class="fa fa-check"></i><b>2.16.1</b> Solution</a></li> |
| <li class="chapter" data-level="2.16.2" data-path="reading-and-writing-data---single-files.html"><a href="reading-and-writing-data---single-files.html#discussion-3"><i class="fa fa-check"></i><b>2.16.2</b> Discussion</a></li> |
| </ul></li> |
| </ul></li> |
| <li class="chapter" data-level="3" data-path="reading-and-writing-data---multiple-files.html"><a href="reading-and-writing-data---multiple-files.html"><i class="fa fa-check"></i><b>3</b> Reading and Writing Data - Multiple Files</a> |
| <ul> |
| <li class="chapter" data-level="3.1" data-path="reading-and-writing-data---multiple-files.html"><a href="reading-and-writing-data---multiple-files.html#introduction-1"><i class="fa fa-check"></i><b>3.1</b> Introduction</a></li> |
| <li class="chapter" data-level="3.2" data-path="reading-and-writing-data---multiple-files.html"><a href="reading-and-writing-data---multiple-files.html#write-data-to-disk---parquet"><i class="fa fa-check"></i><b>3.2</b> Write data to disk - Parquet</a> |
| <ul> |
| <li class="chapter" data-level="3.2.1" data-path="reading-and-writing-data---multiple-files.html"><a href="reading-and-writing-data---multiple-files.html#solution-15"><i class="fa fa-check"></i><b>3.2.1</b> Solution</a></li> |
| <li class="chapter" data-level="3.2.2" data-path="reading-and-writing-data---multiple-files.html"><a href="reading-and-writing-data---multiple-files.html#discussion-4"><i class="fa fa-check"></i><b>3.2.2</b> Discussion</a></li> |
| </ul></li> |
| <li class="chapter" data-level="3.3" data-path="reading-and-writing-data---multiple-files.html"><a href="reading-and-writing-data---multiple-files.html#write-partitioned-data---parquet"><i class="fa fa-check"></i><b>3.3</b> Write partitioned data - Parquet</a> |
| <ul> |
| <li class="chapter" data-level="3.3.1" data-path="reading-and-writing-data---multiple-files.html"><a href="reading-and-writing-data---multiple-files.html#solution-16"><i class="fa fa-check"></i><b>3.3.1</b> Solution</a></li> |
| <li class="chapter" data-level="3.3.2" data-path="reading-and-writing-data---multiple-files.html"><a href="reading-and-writing-data---multiple-files.html#discussion-5"><i class="fa fa-check"></i><b>3.3.2</b> Discussion</a></li> |
| </ul></li> |
| <li class="chapter" data-level="3.4" data-path="reading-and-writing-data---multiple-files.html"><a href="reading-and-writing-data---multiple-files.html#read-partitioned-data"><i class="fa fa-check"></i><b>3.4</b> Read partitioned data</a> |
| <ul> |
| <li class="chapter" data-level="3.4.1" data-path="reading-and-writing-data---multiple-files.html"><a href="reading-and-writing-data---multiple-files.html#solution-17"><i class="fa fa-check"></i><b>3.4.1</b> Solution</a></li> |
| <li class="chapter" data-level="3.4.2" data-path="reading-and-writing-data---multiple-files.html"><a href="reading-and-writing-data---multiple-files.html#discussion-6"><i class="fa fa-check"></i><b>3.4.2</b> Discussion</a></li> |
| </ul></li> |
| <li class="chapter" data-level="3.5" data-path="reading-and-writing-data---multiple-files.html"><a href="reading-and-writing-data---multiple-files.html#write-data-to-disk---featherarrow-ipc-format"><i class="fa fa-check"></i><b>3.5</b> Write data to disk - Feather/Arrow IPC format</a> |
| <ul> |
| <li class="chapter" data-level="3.5.1" data-path="reading-and-writing-data---multiple-files.html"><a href="reading-and-writing-data---multiple-files.html#solution-18"><i class="fa fa-check"></i><b>3.5.1</b> Solution</a></li> |
| </ul></li> |
| <li class="chapter" data-level="3.6" data-path="reading-and-writing-data---multiple-files.html"><a href="reading-and-writing-data---multiple-files.html#read-in-featherarrow-ipc-data-as-an-arrow-dataset"><i class="fa fa-check"></i><b>3.6</b> Read in Feather/Arrow IPC data as an Arrow Dataset</a> |
| <ul> |
| <li class="chapter" data-level="3.6.1" data-path="reading-and-writing-data---multiple-files.html"><a href="reading-and-writing-data---multiple-files.html#solution-19"><i class="fa fa-check"></i><b>3.6.1</b> Solution</a></li> |
| </ul></li> |
| <li class="chapter" data-level="3.7" data-path="reading-and-writing-data---multiple-files.html"><a href="reading-and-writing-data---multiple-files.html#write-data-to-disk---csv-format"><i class="fa fa-check"></i><b>3.7</b> Write data to disk - CSV format</a> |
| <ul> |
| <li class="chapter" data-level="3.7.1" data-path="reading-and-writing-data---multiple-files.html"><a href="reading-and-writing-data---multiple-files.html#solution-20"><i class="fa fa-check"></i><b>3.7.1</b> Solution</a></li> |
| </ul></li> |
| <li class="chapter" data-level="3.8" data-path="reading-and-writing-data---multiple-files.html"><a href="reading-and-writing-data---multiple-files.html#read-in-csv-data-as-an-arrow-dataset"><i class="fa fa-check"></i><b>3.8</b> Read in CSV data as an Arrow Dataset</a> |
| <ul> |
| <li class="chapter" data-level="3.8.1" data-path="reading-and-writing-data---multiple-files.html"><a href="reading-and-writing-data---multiple-files.html#solution-21"><i class="fa fa-check"></i><b>3.8.1</b> Solution</a></li> |
| </ul></li> |
| <li class="chapter" data-level="3.9" data-path="reading-and-writing-data---multiple-files.html"><a href="reading-and-writing-data---multiple-files.html#read-in-a-csv-dataset-no-headers"><i class="fa fa-check"></i><b>3.9</b> Read in a CSV dataset (no headers)</a> |
| <ul> |
| <li class="chapter" data-level="3.9.1" data-path="reading-and-writing-data---multiple-files.html"><a href="reading-and-writing-data---multiple-files.html#solution-22"><i class="fa fa-check"></i><b>3.9.1</b> Solution</a></li> |
| <li class="chapter" data-level="3.9.2" data-path="reading-and-writing-data---multiple-files.html"><a href="reading-and-writing-data---multiple-files.html#discussion-7"><i class="fa fa-check"></i><b>3.9.2</b> Discussion</a></li> |
| </ul></li> |
| <li class="chapter" data-level="3.10" data-path="reading-and-writing-data---multiple-files.html"><a href="reading-and-writing-data---multiple-files.html#write-compressed-partitioned-data"><i class="fa fa-check"></i><b>3.10</b> Write compressed partitioned data</a> |
| <ul> |
| <li class="chapter" data-level="3.10.1" data-path="reading-and-writing-data---multiple-files.html"><a href="reading-and-writing-data---multiple-files.html#solution-23"><i class="fa fa-check"></i><b>3.10.1</b> Solution</a></li> |
| <li class="chapter" data-level="3.10.2" data-path="reading-and-writing-data---multiple-files.html"><a href="reading-and-writing-data---multiple-files.html#discussion-8"><i class="fa fa-check"></i><b>3.10.2</b> Discussion</a></li> |
| </ul></li> |
| <li class="chapter" data-level="3.11" data-path="reading-and-writing-data---multiple-files.html"><a href="reading-and-writing-data---multiple-files.html#read-compressed-data-1"><i class="fa fa-check"></i><b>3.11</b> Read compressed data</a> |
| <ul> |
| <li class="chapter" data-level="3.11.1" data-path="reading-and-writing-data---multiple-files.html"><a href="reading-and-writing-data---multiple-files.html#solution-24"><i class="fa fa-check"></i><b>3.11.1</b> Solution</a></li> |
| <li class="chapter" data-level="3.11.2" data-path="reading-and-writing-data---multiple-files.html"><a href="reading-and-writing-data---multiple-files.html#discussion-9"><i class="fa fa-check"></i><b>3.11.2</b> Discussion</a></li> |
| </ul></li> |
| </ul></li> |
| <li class="chapter" data-level="4" data-path="creating-arrow-objects.html"><a href="creating-arrow-objects.html"><i class="fa fa-check"></i><b>4</b> Creating Arrow Objects</a> |
| <ul> |
| <li class="chapter" data-level="4.1" data-path="creating-arrow-objects.html"><a href="creating-arrow-objects.html#create-an-arrow-array-from-an-r-object"><i class="fa fa-check"></i><b>4.1</b> Create an Arrow Array from an R object</a> |
| <ul> |
| <li class="chapter" data-level="4.1.1" data-path="creating-arrow-objects.html"><a href="creating-arrow-objects.html#solution-25"><i class="fa fa-check"></i><b>4.1.1</b> Solution</a></li> |
| </ul></li> |
| <li class="chapter" data-level="4.2" data-path="creating-arrow-objects.html"><a href="creating-arrow-objects.html#create-a-arrow-table-from-an-r-object"><i class="fa fa-check"></i><b>4.2</b> Create a Arrow Table from an R object</a> |
| <ul> |
| <li class="chapter" data-level="4.2.1" data-path="creating-arrow-objects.html"><a href="creating-arrow-objects.html#solution-26"><i class="fa fa-check"></i><b>4.2.1</b> Solution</a></li> |
| </ul></li> |
| <li class="chapter" data-level="4.3" data-path="creating-arrow-objects.html"><a href="creating-arrow-objects.html#view-the-contents-of-an-arrow-table-or-recordbatch"><i class="fa fa-check"></i><b>4.3</b> View the contents of an Arrow Table or RecordBatch</a> |
| <ul> |
| <li class="chapter" data-level="4.3.1" data-path="creating-arrow-objects.html"><a href="creating-arrow-objects.html#solution-27"><i class="fa fa-check"></i><b>4.3.1</b> Solution</a></li> |
| </ul></li> |
| <li class="chapter" data-level="4.4" data-path="creating-arrow-objects.html"><a href="creating-arrow-objects.html#manually-create-a-recordbatch-from-an-r-object."><i class="fa fa-check"></i><b>4.4</b> Manually create a RecordBatch from an R object.</a> |
| <ul> |
| <li class="chapter" data-level="4.4.1" data-path="creating-arrow-objects.html"><a href="creating-arrow-objects.html#solution-28"><i class="fa fa-check"></i><b>4.4.1</b> Solution</a></li> |
| </ul></li> |
| </ul></li> |
| <li class="chapter" data-level="5" data-path="defining-data-types.html"><a href="defining-data-types.html"><i class="fa fa-check"></i><b>5</b> Defining Data Types</a> |
| <ul> |
| <li class="chapter" data-level="5.1" data-path="defining-data-types.html"><a href="defining-data-types.html#introduction-2"><i class="fa fa-check"></i><b>5.1</b> Introduction</a></li> |
| <li class="chapter" data-level="5.2" data-path="defining-data-types.html"><a href="defining-data-types.html#update-data-type-of-an-existing-arrow-array"><i class="fa fa-check"></i><b>5.2</b> Update data type of an existing Arrow Array</a> |
| <ul> |
| <li class="chapter" data-level="5.2.1" data-path="defining-data-types.html"><a href="defining-data-types.html#solution-29"><i class="fa fa-check"></i><b>5.2.1</b> Solution</a></li> |
| <li class="chapter" data-level="5.2.2" data-path="defining-data-types.html"><a href="defining-data-types.html#discussion-10"><i class="fa fa-check"></i><b>5.2.2</b> Discussion</a></li> |
| </ul></li> |
| <li class="chapter" data-level="5.3" data-path="defining-data-types.html"><a href="defining-data-types.html#update-data-type-of-a-field-in-an-existing-arrow-table"><i class="fa fa-check"></i><b>5.3</b> Update data type of a field in an existing Arrow Table</a> |
| <ul> |
| <li class="chapter" data-level="5.3.1" data-path="defining-data-types.html"><a href="defining-data-types.html#solution-30"><i class="fa fa-check"></i><b>5.3.1</b> Solution</a></li> |
| <li class="chapter" data-level="5.3.2" data-path="defining-data-types.html"><a href="defining-data-types.html#no-compat-type"><i class="fa fa-check"></i><b>5.3.2</b> Discussion</a></li> |
| </ul></li> |
| <li class="chapter" data-level="5.4" data-path="defining-data-types.html"><a href="defining-data-types.html#specify-data-types-when-creating-an-arrow-table-from-an-r-object"><i class="fa fa-check"></i><b>5.4</b> Specify data types when creating an Arrow table from an R object</a> |
| <ul> |
| <li class="chapter" data-level="5.4.1" data-path="defining-data-types.html"><a href="defining-data-types.html#solution-31"><i class="fa fa-check"></i><b>5.4.1</b> Solution</a></li> |
| </ul></li> |
| <li class="chapter" data-level="5.5" data-path="defining-data-types.html"><a href="defining-data-types.html#specify-data-types-when-reading-in-files"><i class="fa fa-check"></i><b>5.5</b> Specify data types when reading in files</a> |
| <ul> |
| <li class="chapter" data-level="5.5.1" data-path="defining-data-types.html"><a href="defining-data-types.html#solution-32"><i class="fa fa-check"></i><b>5.5.1</b> Solution</a></li> |
| </ul></li> |
| </ul></li> |
| <li class="chapter" data-level="6" data-path="manipulating-data---arrays.html"><a href="manipulating-data---arrays.html"><i class="fa fa-check"></i><b>6</b> Manipulating Data - Arrays</a> |
| <ul> |
| <li class="chapter" data-level="6.1" data-path="manipulating-data---arrays.html"><a href="manipulating-data---arrays.html#introduction-3"><i class="fa fa-check"></i><b>6.1</b> Introduction</a></li> |
| <li class="chapter" data-level="6.2" data-path="manipulating-data---arrays.html"><a href="manipulating-data---arrays.html#filter-by-values-matching-a-predicate-or-mask"><i class="fa fa-check"></i><b>6.2</b> Filter by values matching a predicate or mask</a> |
| <ul> |
| <li class="chapter" data-level="6.2.1" data-path="manipulating-data---arrays.html"><a href="manipulating-data---arrays.html#solution-33"><i class="fa fa-check"></i><b>6.2.1</b> Solution</a></li> |
| <li class="chapter" data-level="6.2.2" data-path="manipulating-data---arrays.html"><a href="manipulating-data---arrays.html#discussion-11"><i class="fa fa-check"></i><b>6.2.2</b> Discussion</a></li> |
| </ul></li> |
| <li class="chapter" data-level="6.3" data-path="manipulating-data---arrays.html"><a href="manipulating-data---arrays.html#compute-meanminmax-etc-value-of-an-array"><i class="fa fa-check"></i><b>6.3</b> Compute Mean/Min/Max, etc value of an Array</a> |
| <ul> |
| <li class="chapter" data-level="6.3.1" data-path="manipulating-data---arrays.html"><a href="manipulating-data---arrays.html#solution-34"><i class="fa fa-check"></i><b>6.3.1</b> Solution</a></li> |
| <li class="chapter" data-level="6.3.2" data-path="manipulating-data---arrays.html"><a href="manipulating-data---arrays.html#discussion-12"><i class="fa fa-check"></i><b>6.3.2</b> Discussion</a></li> |
| </ul></li> |
| <li class="chapter" data-level="6.4" data-path="manipulating-data---arrays.html"><a href="manipulating-data---arrays.html#count-occurrences-of-elements-in-an-array"><i class="fa fa-check"></i><b>6.4</b> Count occurrences of elements in an Array</a> |
| <ul> |
| <li class="chapter" data-level="6.4.1" data-path="manipulating-data---arrays.html"><a href="manipulating-data---arrays.html#solution-35"><i class="fa fa-check"></i><b>6.4.1</b> Solution</a></li> |
| <li class="chapter" data-level="6.4.2" data-path="manipulating-data---arrays.html"><a href="manipulating-data---arrays.html#discussion-13"><i class="fa fa-check"></i><b>6.4.2</b> Discussion</a></li> |
| </ul></li> |
| <li class="chapter" data-level="6.5" data-path="manipulating-data---arrays.html"><a href="manipulating-data---arrays.html#apply-arithmetic-functions-to-arrays."><i class="fa fa-check"></i><b>6.5</b> Apply arithmetic functions to Arrays.</a> |
| <ul> |
| <li class="chapter" data-level="6.5.1" data-path="manipulating-data---arrays.html"><a href="manipulating-data---arrays.html#solution-36"><i class="fa fa-check"></i><b>6.5.1</b> Solution</a></li> |
| <li class="chapter" data-level="6.5.2" data-path="manipulating-data---arrays.html"><a href="manipulating-data---arrays.html#discussion-14"><i class="fa fa-check"></i><b>6.5.2</b> Discussion</a></li> |
| </ul></li> |
| <li class="chapter" data-level="6.6" data-path="manipulating-data---arrays.html"><a href="manipulating-data---arrays.html#call-arrow-compute-functions-directly-on-arrays"><i class="fa fa-check"></i><b>6.6</b> Call Arrow compute functions directly on Arrays</a> |
| <ul> |
| <li class="chapter" data-level="6.6.1" data-path="manipulating-data---arrays.html"><a href="manipulating-data---arrays.html#solution-37"><i class="fa fa-check"></i><b>6.6.1</b> Solution</a></li> |
| <li class="chapter" data-level="6.6.2" data-path="manipulating-data---arrays.html"><a href="manipulating-data---arrays.html#discussion-15"><i class="fa fa-check"></i><b>6.6.2</b> Discussion</a></li> |
| <li class="chapter" data-level="6.6.3" data-path="manipulating-data---arrays.html"><a href="manipulating-data---arrays.html#see-also-2"><i class="fa fa-check"></i><b>6.6.3</b> See also</a></li> |
| </ul></li> |
| </ul></li> |
| <li class="chapter" data-level="7" data-path="manipulating-data---tables.html"><a href="manipulating-data---tables.html"><i class="fa fa-check"></i><b>7</b> Manipulating Data - Tables</a> |
| <ul> |
| <li class="chapter" data-level="7.1" data-path="manipulating-data---tables.html"><a href="manipulating-data---tables.html#introduction-4"><i class="fa fa-check"></i><b>7.1</b> Introduction</a></li> |
| <li class="chapter" data-level="7.2" data-path="manipulating-data---tables.html"><a href="manipulating-data---tables.html#use-dplyr-verbs-in-arrow"><i class="fa fa-check"></i><b>7.2</b> Use dplyr verbs in Arrow</a> |
| <ul> |
| <li class="chapter" data-level="7.2.1" data-path="manipulating-data---tables.html"><a href="manipulating-data---tables.html#solution-38"><i class="fa fa-check"></i><b>7.2.1</b> Solution</a></li> |
| <li class="chapter" data-level="7.2.2" data-path="manipulating-data---tables.html"><a href="manipulating-data---tables.html#discussion-16"><i class="fa fa-check"></i><b>7.2.2</b> Discussion</a></li> |
| <li class="chapter" data-level="7.2.3" data-path="manipulating-data---tables.html"><a href="manipulating-data---tables.html#see-also-3"><i class="fa fa-check"></i><b>7.2.3</b> See also</a></li> |
| </ul></li> |
| <li class="chapter" data-level="7.3" data-path="manipulating-data---tables.html"><a href="manipulating-data---tables.html#use-r-functions-in-dplyr-verbs-in-arrow"><i class="fa fa-check"></i><b>7.3</b> Use R functions in dplyr verbs in Arrow</a> |
| <ul> |
| <li class="chapter" data-level="7.3.1" data-path="manipulating-data---tables.html"><a href="manipulating-data---tables.html#solution-39"><i class="fa fa-check"></i><b>7.3.1</b> Solution</a></li> |
| <li class="chapter" data-level="7.3.2" data-path="manipulating-data---tables.html"><a href="manipulating-data---tables.html#discussion-17"><i class="fa fa-check"></i><b>7.3.2</b> Discussion</a></li> |
| </ul></li> |
| <li class="chapter" data-level="7.4" data-path="manipulating-data---tables.html"><a href="manipulating-data---tables.html#use-arrow-functions-in-dplyr-verbs-in-arrow"><i class="fa fa-check"></i><b>7.4</b> Use Arrow functions in dplyr verbs in Arrow</a> |
| <ul> |
| <li class="chapter" data-level="7.4.1" data-path="manipulating-data---tables.html"><a href="manipulating-data---tables.html#solution-40"><i class="fa fa-check"></i><b>7.4.1</b> Solution</a></li> |
| <li class="chapter" data-level="7.4.2" data-path="manipulating-data---tables.html"><a href="manipulating-data---tables.html#discussion-18"><i class="fa fa-check"></i><b>7.4.2</b> Discussion</a></li> |
| </ul></li> |
| <li class="chapter" data-level="7.5" data-path="manipulating-data---tables.html"><a href="manipulating-data---tables.html#compute-window-aggregates"><i class="fa fa-check"></i><b>7.5</b> Compute Window Aggregates</a> |
| <ul> |
| <li class="chapter" data-level="7.5.1" data-path="manipulating-data---tables.html"><a href="manipulating-data---tables.html#solution-41"><i class="fa fa-check"></i><b>7.5.1</b> Solution</a></li> |
| <li class="chapter" data-level="7.5.2" data-path="manipulating-data---tables.html"><a href="manipulating-data---tables.html#discusson"><i class="fa fa-check"></i><b>7.5.2</b> Discusson</a></li> |
| </ul></li> |
| </ul></li> |
| <li class="chapter" data-level="8" data-path="using-pyarrow-from-r.html"><a href="using-pyarrow-from-r.html"><i class="fa fa-check"></i><b>8</b> Using PyArrow from R</a> |
| <ul> |
| <li class="chapter" data-level="8.1" data-path="using-pyarrow-from-r.html"><a href="using-pyarrow-from-r.html#introduction-5"><i class="fa fa-check"></i><b>8.1</b> Introduction</a></li> |
| <li class="chapter" data-level="8.2" data-path="using-pyarrow-from-r.html"><a href="using-pyarrow-from-r.html#create-an-arrow-object-using-pyarrow-in-r"><i class="fa fa-check"></i><b>8.2</b> Create an Arrow object using PyArrow in R</a> |
| <ul> |
| <li class="chapter" data-level="8.2.1" data-path="using-pyarrow-from-r.html"><a href="using-pyarrow-from-r.html#solution-42"><i class="fa fa-check"></i><b>8.2.1</b> Solution</a></li> |
| </ul></li> |
| <li class="chapter" data-level="8.3" data-path="using-pyarrow-from-r.html"><a href="using-pyarrow-from-r.html#call-a-pyarrow-function-from-r"><i class="fa fa-check"></i><b>8.3</b> Call a PyArrow function from R</a> |
| <ul> |
| <li class="chapter" data-level="8.3.1" data-path="using-pyarrow-from-r.html"><a href="using-pyarrow-from-r.html#solution-43"><i class="fa fa-check"></i><b>8.3.1</b> Solution</a></li> |
| </ul></li> |
| </ul></li> |
| <li class="chapter" data-level="9" data-path="flight.html"><a href="flight.html"><i class="fa fa-check"></i><b>9</b> Flight</a> |
| <ul> |
| <li class="chapter" data-level="9.1" data-path="flight.html"><a href="flight.html#introduction-6"><i class="fa fa-check"></i><b>9.1</b> Introduction</a></li> |
| <li class="chapter" data-level="9.2" data-path="flight.html"><a href="flight.html#connect-to-a-flight-server"><i class="fa fa-check"></i><b>9.2</b> Connect to a Flight server</a> |
| <ul> |
| <li class="chapter" data-level="9.2.1" data-path="flight.html"><a href="flight.html#solution-44"><i class="fa fa-check"></i><b>9.2.1</b> Solution</a></li> |
| <li class="chapter" data-level="9.2.2" data-path="flight.html"><a href="flight.html#see-also-4"><i class="fa fa-check"></i><b>9.2.2</b> See also</a></li> |
| </ul></li> |
| <li class="chapter" data-level="9.3" data-path="flight.html"><a href="flight.html#send-data-to-a-flight-server"><i class="fa fa-check"></i><b>9.3</b> Send data to a Flight server</a> |
| <ul> |
| <li class="chapter" data-level="9.3.1" data-path="flight.html"><a href="flight.html#solution-45"><i class="fa fa-check"></i><b>9.3.1</b> Solution</a></li> |
| </ul></li> |
| <li class="chapter" data-level="9.4" data-path="flight.html"><a href="flight.html#check-what-resources-exist-on-a-flight-server"><i class="fa fa-check"></i><b>9.4</b> Check what resources exist on a Flight server</a> |
| <ul> |
| <li class="chapter" data-level="9.4.1" data-path="flight.html"><a href="flight.html#solution-46"><i class="fa fa-check"></i><b>9.4.1</b> Solution</a></li> |
| </ul></li> |
| <li class="chapter" data-level="9.5" data-path="flight.html"><a href="flight.html#retrieve-data-from-a-flight-server"><i class="fa fa-check"></i><b>9.5</b> Retrieve data from a Flight server</a> |
| <ul> |
| <li class="chapter" data-level="9.5.1" data-path="flight.html"><a href="flight.html#solution-47"><i class="fa fa-check"></i><b>9.5.1</b> Solution</a></li> |
| </ul></li> |
| </ul></li> |
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| <div class="body-inner"> |
| <div class="book-header" role="navigation"> |
| <h1> |
| <i class="fa fa-circle-o-notch fa-spin"></i><a href="./">Apache Arrow R Cookbook</a> |
| </h1> |
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| |
| <section class="normal" id="section-"> |
| <div id="manipulating-data---arrays" class="section level1 hasAnchor" number="6"> |
| <h1><span class="header-section-number">6</span> Manipulating Data - Arrays<a href="manipulating-data---arrays.html#manipulating-data---arrays" class="anchor-section" aria-label="Anchor link to header"></a></h1> |
| <div id="introduction-3" class="section level2 hasAnchor" number="6.1"> |
| <h2><span class="header-section-number">6.1</span> Introduction<a href="manipulating-data---arrays.html#introduction-3" class="anchor-section" aria-label="Anchor link to header"></a></h2> |
| <p>An Arrow Array is roughly equivalent to an R vector - it can be used to |
| represent a single column of data, with all values having the same data type.</p> |
| <p>A number of base R functions which have S3 generic methods have been implemented |
| to work on Arrow Arrays; for example <code>mean</code>, <code>min</code>, and <code>max</code>.</p> |
| </div> |
| <div id="filter-by-values-matching-a-predicate-or-mask" class="section level2 hasAnchor" number="6.2"> |
| <h2><span class="header-section-number">6.2</span> Filter by values matching a predicate or mask<a href="manipulating-data---arrays.html#filter-by-values-matching-a-predicate-or-mask" class="anchor-section" aria-label="Anchor link to header"></a></h2> |
| <p>You want to search for values in an Array that match a predicate condition.</p> |
| <div id="solution-33" class="section level3 hasAnchor" number="6.2.1"> |
| <h3><span class="header-section-number">6.2.1</span> Solution<a href="manipulating-data---arrays.html#solution-33" class="anchor-section" aria-label="Anchor link to header"></a></h3> |
| <div class="sourceCode" id="cb85"><pre class="sourceCode r"><code class="sourceCode r"><span id="cb85-1"><a href="manipulating-data---arrays.html#cb85-1" aria-hidden="true" tabindex="-1"></a>my_values <span class="ot"><-</span> Array<span class="sc">$</span><span class="fu">create</span>(<span class="fu">c</span>(<span class="dv">1</span><span class="sc">:</span><span class="dv">5</span>, <span class="cn">NA</span>))</span> |
| <span id="cb85-2"><a href="manipulating-data---arrays.html#cb85-2" aria-hidden="true" tabindex="-1"></a>my_values[my_values <span class="sc">></span> <span class="dv">3</span>]</span></code></pre></div> |
| <pre><code>## Array |
| ## <int32> |
| ## [ |
| ## 4, |
| ## 5, |
| ## null |
| ## ]</code></pre> |
| </div> |
| <div id="discussion-11" class="section level3 hasAnchor" number="6.2.2"> |
| <h3><span class="header-section-number">6.2.2</span> Discussion<a href="manipulating-data---arrays.html#discussion-11" class="anchor-section" aria-label="Anchor link to header"></a></h3> |
| <p>You can refer to items in an Array using the square brackets <code>[]</code> like you can |
| an R vector.</p> |
| </div> |
| </div> |
| <div id="compute-meanminmax-etc-value-of-an-array" class="section level2 hasAnchor" number="6.3"> |
| <h2><span class="header-section-number">6.3</span> Compute Mean/Min/Max, etc value of an Array<a href="manipulating-data---arrays.html#compute-meanminmax-etc-value-of-an-array" class="anchor-section" aria-label="Anchor link to header"></a></h2> |
| <p>You want to calculate the mean, minimum, or maximum of values in an array.</p> |
| <div id="solution-34" class="section level3 hasAnchor" number="6.3.1"> |
| <h3><span class="header-section-number">6.3.1</span> Solution<a href="manipulating-data---arrays.html#solution-34" class="anchor-section" aria-label="Anchor link to header"></a></h3> |
| <div class="sourceCode" id="cb87"><pre class="sourceCode r"><code class="sourceCode r"><span id="cb87-1"><a href="manipulating-data---arrays.html#cb87-1" aria-hidden="true" tabindex="-1"></a>my_values <span class="ot"><-</span> Array<span class="sc">$</span><span class="fu">create</span>(<span class="fu">c</span>(<span class="dv">1</span><span class="sc">:</span><span class="dv">5</span>, <span class="cn">NA</span>))</span> |
| <span id="cb87-2"><a href="manipulating-data---arrays.html#cb87-2" aria-hidden="true" tabindex="-1"></a><span class="fu">mean</span>(my_values, <span class="at">na.rm =</span> <span class="cn">TRUE</span>)</span></code></pre></div> |
| <pre><code>## Scalar |
| ## 3</code></pre> |
| </div> |
| <div id="discussion-12" class="section level3 hasAnchor" number="6.3.2"> |
| <h3><span class="header-section-number">6.3.2</span> Discussion<a href="manipulating-data---arrays.html#discussion-12" class="anchor-section" aria-label="Anchor link to header"></a></h3> |
| <p>Many base R generic functions such as <code>mean()</code>, <code>min()</code>, and <code>max()</code> have been |
| mapped to their Arrow equivalents, and so can be called on Arrow Array objects |
| in the same way. They will return Arrow objects themselves.</p> |
| <p>If you want to use an R function which does not have an Arrow mapping, you can |
| use <code>as.vector()</code> to convert Arrow objects to base R vectors.</p> |
| <div class="sourceCode" id="cb89"><pre class="sourceCode r"><code class="sourceCode r"><span id="cb89-1"><a href="manipulating-data---arrays.html#cb89-1" aria-hidden="true" tabindex="-1"></a>arrow_array <span class="ot"><-</span> Array<span class="sc">$</span><span class="fu">create</span>(<span class="dv">1</span><span class="sc">:</span><span class="dv">100</span>)</span> |
| <span id="cb89-2"><a href="manipulating-data---arrays.html#cb89-2" aria-hidden="true" tabindex="-1"></a><span class="co"># get Tukey's five-number summary</span></span> |
| <span id="cb89-3"><a href="manipulating-data---arrays.html#cb89-3" aria-hidden="true" tabindex="-1"></a><span class="fu">fivenum</span>(<span class="fu">as.vector</span>(arrow_array))</span></code></pre></div> |
| <pre><code>## [1] 1.0 25.5 50.5 75.5 100.0</code></pre> |
| <p>You can tell if a function is a standard S3 generic function by looking |
| at the body of the function - S3 generic functions call <code>UseMethod()</code> |
| to determine the appropriate version of that function to use for the object.</p> |
| <div class="sourceCode" id="cb91"><pre class="sourceCode r"><code class="sourceCode r"><span id="cb91-1"><a href="manipulating-data---arrays.html#cb91-1" aria-hidden="true" tabindex="-1"></a>mean</span></code></pre></div> |
| <pre><code>## function (x, ...) |
| ## UseMethod("mean") |
| ## <bytecode: 0x564a10424388> |
| ## <environment: namespace:base></code></pre> |
| <p>You can also use <code>isS3stdGeneric()</code> to determine if a function is an S3 generic.</p> |
| <div class="sourceCode" id="cb93"><pre class="sourceCode r"><code class="sourceCode r"><span id="cb93-1"><a href="manipulating-data---arrays.html#cb93-1" aria-hidden="true" tabindex="-1"></a><span class="fu">isS3stdGeneric</span>(<span class="st">"mean"</span>)</span></code></pre></div> |
| <pre><code>## mean |
| ## TRUE</code></pre> |
| <p>If you find an S3 generic function which isn’t implemented for Arrow objects |
| but you would like to be able to use, please |
| <a href="https://issues.apache.org/jira/projects/ARROW/issues">open an issue on the project JIRA</a>.</p> |
| </div> |
| </div> |
| <div id="count-occurrences-of-elements-in-an-array" class="section level2 hasAnchor" number="6.4"> |
| <h2><span class="header-section-number">6.4</span> Count occurrences of elements in an Array<a href="manipulating-data---arrays.html#count-occurrences-of-elements-in-an-array" class="anchor-section" aria-label="Anchor link to header"></a></h2> |
| <p>You want to count repeated values in an Array.</p> |
| <div id="solution-35" class="section level3 hasAnchor" number="6.4.1"> |
| <h3><span class="header-section-number">6.4.1</span> Solution<a href="manipulating-data---arrays.html#solution-35" class="anchor-section" aria-label="Anchor link to header"></a></h3> |
| <div class="sourceCode" id="cb95"><pre class="sourceCode r"><code class="sourceCode r"><span id="cb95-1"><a href="manipulating-data---arrays.html#cb95-1" aria-hidden="true" tabindex="-1"></a>repeated_vals <span class="ot"><-</span> Array<span class="sc">$</span><span class="fu">create</span>(<span class="fu">c</span>(<span class="dv">1</span>, <span class="dv">1</span>, <span class="dv">2</span>, <span class="dv">3</span>, <span class="dv">3</span>, <span class="dv">3</span>, <span class="dv">3</span>, <span class="dv">3</span>))</span> |
| <span id="cb95-2"><a href="manipulating-data---arrays.html#cb95-2" aria-hidden="true" tabindex="-1"></a><span class="fu">value_counts</span>(repeated_vals)</span></code></pre></div> |
| <pre><code>## StructArray |
| ## <struct<values: double, counts: int64>> |
| ## -- is_valid: all not null |
| ## -- child 0 type: double |
| ## [ |
| ## 1, |
| ## 2, |
| ## 3 |
| ## ] |
| ## -- child 1 type: int64 |
| ## [ |
| ## 2, |
| ## 1, |
| ## 5 |
| ## ]</code></pre> |
| </div> |
| <div id="discussion-13" class="section level3 hasAnchor" number="6.4.2"> |
| <h3><span class="header-section-number">6.4.2</span> Discussion<a href="manipulating-data---arrays.html#discussion-13" class="anchor-section" aria-label="Anchor link to header"></a></h3> |
| <p>Some functions in the Arrow R package do not have base R equivalents. In other |
| cases, the base R equivalents are not generic functions so they cannot be called |
| directly on Arrow Array objects.</p> |
| <p>For example, the <code>value_counts()</code> function in the Arrow R package is loosely |
| equivalent to the base R function <code>table()</code>, which is not a generic function.</p> |
| </div> |
| </div> |
| <div id="apply-arithmetic-functions-to-arrays." class="section level2 hasAnchor" number="6.5"> |
| <h2><span class="header-section-number">6.5</span> Apply arithmetic functions to Arrays.<a href="manipulating-data---arrays.html#apply-arithmetic-functions-to-arrays." class="anchor-section" aria-label="Anchor link to header"></a></h2> |
| <p>You want to use the various arithmetic operators on Array objects.</p> |
| <div id="solution-36" class="section level3 hasAnchor" number="6.5.1"> |
| <h3><span class="header-section-number">6.5.1</span> Solution<a href="manipulating-data---arrays.html#solution-36" class="anchor-section" aria-label="Anchor link to header"></a></h3> |
| <div class="sourceCode" id="cb97"><pre class="sourceCode r"><code class="sourceCode r"><span id="cb97-1"><a href="manipulating-data---arrays.html#cb97-1" aria-hidden="true" tabindex="-1"></a>num_array <span class="ot"><-</span> Array<span class="sc">$</span><span class="fu">create</span>(<span class="dv">1</span><span class="sc">:</span><span class="dv">10</span>)</span> |
| <span id="cb97-2"><a href="manipulating-data---arrays.html#cb97-2" aria-hidden="true" tabindex="-1"></a>num_array <span class="sc">+</span> <span class="dv">10</span></span></code></pre></div> |
| <pre><code>## Array |
| ## <double> |
| ## [ |
| ## 11, |
| ## 12, |
| ## 13, |
| ## 14, |
| ## 15, |
| ## 16, |
| ## 17, |
| ## 18, |
| ## 19, |
| ## 20 |
| ## ]</code></pre> |
| </div> |
| <div id="discussion-14" class="section level3 hasAnchor" number="6.5.2"> |
| <h3><span class="header-section-number">6.5.2</span> Discussion<a href="manipulating-data---arrays.html#discussion-14" class="anchor-section" aria-label="Anchor link to header"></a></h3> |
| <p>You will get the same result if you pass in the value you’re adding as an Arrow object.</p> |
| <div class="sourceCode" id="cb99"><pre class="sourceCode r"><code class="sourceCode r"><span id="cb99-1"><a href="manipulating-data---arrays.html#cb99-1" aria-hidden="true" tabindex="-1"></a>num_array <span class="sc">+</span> Scalar<span class="sc">$</span><span class="fu">create</span>(<span class="dv">10</span>)</span></code></pre></div> |
| <pre><code>## Array |
| ## <double> |
| ## [ |
| ## 11, |
| ## 12, |
| ## 13, |
| ## 14, |
| ## 15, |
| ## 16, |
| ## 17, |
| ## 18, |
| ## 19, |
| ## 20 |
| ## ]</code></pre> |
| </div> |
| </div> |
| <div id="call-arrow-compute-functions-directly-on-arrays" class="section level2 hasAnchor" number="6.6"> |
| <h2><span class="header-section-number">6.6</span> Call Arrow compute functions directly on Arrays<a href="manipulating-data---arrays.html#call-arrow-compute-functions-directly-on-arrays" class="anchor-section" aria-label="Anchor link to header"></a></h2> |
| <p>You want to call an Arrow compute function directly on an Array.</p> |
| <div id="solution-37" class="section level3 hasAnchor" number="6.6.1"> |
| <h3><span class="header-section-number">6.6.1</span> Solution<a href="manipulating-data---arrays.html#solution-37" class="anchor-section" aria-label="Anchor link to header"></a></h3> |
| <div class="sourceCode" id="cb101"><pre class="sourceCode r"><code class="sourceCode r"><span id="cb101-1"><a href="manipulating-data---arrays.html#cb101-1" aria-hidden="true" tabindex="-1"></a>first_100_numbers <span class="ot"><-</span> Array<span class="sc">$</span><span class="fu">create</span>(<span class="dv">1</span><span class="sc">:</span><span class="dv">100</span>)</span> |
| <span id="cb101-2"><a href="manipulating-data---arrays.html#cb101-2" aria-hidden="true" tabindex="-1"></a></span> |
| <span id="cb101-3"><a href="manipulating-data---arrays.html#cb101-3" aria-hidden="true" tabindex="-1"></a><span class="co"># Calculate the variance of 1 to 100, setting the delta degrees of freedom to 0.</span></span> |
| <span id="cb101-4"><a href="manipulating-data---arrays.html#cb101-4" aria-hidden="true" tabindex="-1"></a><span class="fu">call_function</span>(<span class="st">"variance"</span>, first_100_numbers, <span class="at">options =</span> <span class="fu">list</span>(<span class="at">ddof =</span> <span class="dv">0</span>))</span></code></pre></div> |
| <pre><code>## Scalar |
| ## 833.25</code></pre> |
| </div> |
| <div id="discussion-15" class="section level3 hasAnchor" number="6.6.2"> |
| <h3><span class="header-section-number">6.6.2</span> Discussion<a href="manipulating-data---arrays.html#discussion-15" class="anchor-section" aria-label="Anchor link to header"></a></h3> |
| <p>You can use <code>call_function()</code> to call Arrow compute functions directly on |
| Scalar, Array, and ChunkedArray objects. The returned object will be an Arrow object.</p> |
| </div> |
| <div id="see-also-2" class="section level3 hasAnchor" number="6.6.3"> |
| <h3><span class="header-section-number">6.6.3</span> See also<a href="manipulating-data---arrays.html#see-also-2" class="anchor-section" aria-label="Anchor link to header"></a></h3> |
| <p>For a more in-depth discussion of Arrow compute functions, see the section on <a href="manipulating-data---tables.html#use-arrow-functions-in-dplyr-verbs-in-arrow">using arrow functions in dplyr verbs in arrow</a></p> |
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