dataframe

Operate with data in a dataframe format.

This command requires a plugin

The polars command resides in the polars plugin. To use this command, you must install and register nu_plugin_polars. See the Plugins chapter in the book for more information.

Signature

> polars {flags}

Input/output types:

input	output
nothing	string

Notes

You must use one of the following subcommands. Using this command as-is will only produce this help message.

Subcommands:

name	description	type
polars agg	Performs a series of aggregations from a group-by.	plugin
polars agg-groups	Creates an agg_groups expression.	plugin
polars all-false	Returns true if all values are false.	plugin
polars all-true	Returns true if all values are true.	plugin
polars append	Appends a new dataframe.	plugin
polars arg-max	Return index for max value in series.	plugin
polars arg-min	Return index for min value in series.	plugin
polars arg-sort	Returns indexes for a sorted series.	plugin
polars arg-true	Returns indexes where values are true.	plugin
polars arg-unique	Returns indexes for unique values.	plugin
polars arg-where	Creates an expression that returns the arguments where expression is true.	plugin
polars as	Creates an alias expression.	plugin
polars as-date	Converts string to date.	plugin
polars as-datetime	Converts string to datetime.	plugin
polars cache	Caches operations in a new LazyFrame.	plugin
polars cast	Cast a column to a different dtype.	plugin
polars col	Creates a named column expression.	plugin
polars collect	Collect lazy dataframe into eager dataframe.	plugin
polars columns	Show dataframe columns.	plugin
polars concat	Concatenate two or more dataframes.	plugin
polars concat-str	Creates a concat string expression.	plugin
polars contains	Checks if a pattern is contained in a string.	plugin
polars count	Returns the number of non-null values in the column.	plugin
polars count-null	Counts null values.	plugin
polars cumulative	Cumulative calculation for a column or series.	plugin
polars datepart	Creates an expression for capturing the specified datepart in a column.	plugin
polars decimal	Converts a string column into a decimal column	plugin
polars drop	Creates a new dataframe by dropping the selected columns.	plugin
polars drop-duplicates	Drops duplicate values in dataframe.	plugin
polars drop-nulls	Drops null values in dataframe.	plugin
polars dummies	Creates a new dataframe with dummy variables.	plugin
polars explode	Explodes a dataframe or creates a explode expression.	plugin
polars expr-not	Creates a not expression.	plugin
polars fetch	Collects the lazyframe to the selected rows.	plugin
polars fill-nan	Replaces NaN values with the given expression.	plugin
polars fill-null	Replaces NULL values with the given expression.	plugin
polars filter	Filter dataframe based in expression.	plugin
polars filter-with	Filters dataframe using a mask or expression as reference.	plugin
polars first	Show only the first number of rows or create a first expression	plugin
polars flatten	An alias for polars explode.	plugin
polars get	Creates dataframe with the selected columns.	plugin
polars get-day	Gets day from date.	plugin
polars get-hour	Gets hour from date.	plugin
polars get-minute	Gets minute from date.	plugin
polars get-month	Gets month from date.	plugin
polars get-nanosecond	Gets nanosecond from date.	plugin
polars get-ordinal	Gets ordinal from date.	plugin
polars get-second	Gets second from date.	plugin
polars get-week	Gets week from date.	plugin
polars get-weekday	Gets weekday from date.	plugin
polars get-year	Gets year from date.	plugin
polars group-by	Creates a group-by object that can be used for other aggregations.	plugin
polars implode	Aggregates values into a list.	plugin
polars integer	Converts a string column into a integer column	plugin
polars into-df	Converts a list, table or record into a dataframe.	plugin
polars into-lazy	Converts a dataframe into a lazy dataframe.	plugin
polars into-nu	Converts a dataframe or an expression into nushell value for access and exploration.	plugin
polars is-duplicated	Creates mask indicating duplicated values.	plugin
polars is-in	Creates an is-in expression or checks to see if the elements are contained in the right series	plugin
polars is-not-null	Creates mask where value is not null.	plugin
polars is-null	Creates mask where value is null.	plugin
polars is-unique	Creates mask indicating unique values.	plugin
polars join	Joins a lazy frame with other lazy frame.	plugin
polars last	Creates new dataframe with tail rows or creates a last expression.	plugin
polars len	Return the number of rows in the context. This is similar to COUNT(*) in SQL.	plugin
polars lit	Creates a literal expression.	plugin
polars lowercase	Lowercase the strings in the column.	plugin
polars max	Creates a max expression or aggregates columns to their max value.	plugin
polars mean	Creates a mean expression for an aggregation or aggregates columns to their mean value.	plugin
polars median	Median value from columns in a dataframe or creates expression for an aggregation	plugin
polars min	Creates a min expression or aggregates columns to their min value.	plugin
polars n-unique	Counts unique values.	plugin
polars not	Inverts boolean mask.	plugin
polars open	Opens CSV, JSON, NDJSON/JSON lines, arrow, avro, or parquet file to create dataframe. A lazy dataframe will be created by default, if supported.	plugin
polars otherwise	Completes a when expression.	plugin
polars pivot	Pivot a DataFrame from wide to long format.	plugin
polars profile	Profile a lazy dataframe. This will run the query and return a record containing the materialized DataFrame and a DataFrame that contains profiling information of each node that is executed.

The units of the timings are microseconds. | plugin | | polars quantile | Aggregates the columns to the selected quantile. | plugin | | polars query | Query dataframe using SQL. Note: The dataframe is always named 'df' in your query's from clause. | plugin | | polars rename | Rename a dataframe column. | plugin | | polars replace | Replace the leftmost (sub)string by a regex pattern. | plugin | | polars replace-all | Replace all (sub)strings by a regex pattern. | plugin | | polars reverse | Reverses the LazyFrame | plugin | | polars rolling | Rolling calculation for a series. | plugin | | polars sample | Create sample dataframe. | plugin | | polars save | Saves a dataframe to disk. For lazy dataframes a sink operation will be used if the file type supports it (parquet, ipc/arrow, csv, and ndjson). | plugin | | polars schema | Show schema for a dataframe. | plugin | | polars select | Selects columns from lazyframe. | plugin | | polars set | Sets value where given mask is true. | plugin | | polars set-with-idx | Sets value in the given index. | plugin | | polars shape | Shows column and row size for a dataframe. | plugin | | polars shift | Shifts the values by a given period. | plugin | | polars slice | Creates new dataframe from a slice of rows. | plugin | | polars sort-by | Sorts a lazy dataframe based on expression(s). | plugin | | polars std | Creates a std expression for an aggregation of std value from columns in a dataframe. | plugin | | polars store-get | Gets a Dataframe or other object from the plugin cache. | plugin | | polars store-ls | Lists stored polars objects. | plugin | | polars store-rm | Removes a stored Dataframe or other object from the plugin cache. | plugin | | polars str-join | Concatenates strings within a column or dataframes | plugin | | polars str-lengths | Get lengths of all strings. | plugin | | polars str-slice | Slices the string from the start position until the selected length. | plugin | | polars strftime | Formats date based on string rule. | plugin | | polars sum | Creates a sum expression for an aggregation or aggregates columns to their sum value. | plugin | | polars summary | For a dataframe, produces descriptive statistics (summary statistics) for its numeric columns. | plugin | | polars take | Creates new dataframe using the given indices. | plugin | | polars unique | Returns unique values from a dataframe. | plugin | | polars unnest | Decompose struct columns into separate columns for each of their fields. The new columns will be inserted into the dataframe at the location of the struct column. | plugin | | polars unpivot | Unpivot a DataFrame from wide to long format. | plugin | | polars uppercase | Uppercase the strings in the column. | plugin | | polars value-counts | Returns a dataframe with the counts for unique values in series. | plugin | | polars var | Create a var expression for an aggregation. | plugin | | polars when | Creates and modifies a when expression. | plugin | | polars with-column | Adds a series to the dataframe. | plugin |