line

Line plots show the relationship between two numerical columns, optionally grouped by categorical columns.

If multiple Y values are provided for each X value then the plot will show an estimate of the central tendency of X and confidence interval for the estimate.

Usage

gurita line [-h] [-x COLUMN] [-y COLUMN] ... other arguments ...

Arguments

Argument	Description	Reference
-h	display help	help
-x COLUMN --xaxis COLUMN	select column for the X axis	X axis
-y COLUMN --yaxis COLUMN	select column for the Y axis	Y axis
--hue COLUMN	group columns by hue	hue
--hueorder VALUE [VALUE ...]	order of hue columns	hue order
--logx	log scale X axis	log X axis
--logy	log scale Y axis	log Y axis
--xlim BOUND BOUND	range limit X axis	limit X axis
--ylim BOUND BOUND	range limit Y axis	limit Y axis
--frow COLUMN	column to use for facet rows	facet rows
--fcol COLUMN	column to use for facet columns	facet columns
--fcolwrap INT	wrap the facet column at this width, to span multiple rows	facet wrap

See also

Line plots are based on Seaborn’s relplot library function, using the kind="line" option.

Simple example

A line plot showing the relationship between timepoint on the X axis and signal on the Y axis for the fmri.csv dataset:

gurita line -x timepoint -y signal < fmri.csv

The output of the above command is written to line.timepoint.signal.png.

Getting help

The full set of command line arguments for line plots can be obtained with the -h or --help arguments:

gurita line -h

Selecting columns to plot

-x COLUMN, --xaxis COLUMN
-y COLUMN, --yaxis COLUMN

Line plots show an indepdent numerical column on the X axis and a depdendent numerical column on the Y axis.

Grouping columns with hue

--hue COLUMN

The data can be grouped by a categorical column with the --hue argument.

In the following example signal is plotted against timepoint for the two different classes of the event column in the fmri.csv dataset:

gurita line -x timepoint -y signal --hue event < fmri.csv

By default the order of the columns within each hue group is determined from their occurrence in the input data. This can be overridden with the --hueorder argument, which allows you to specify the exact ordering of columns within each hue group, based on their values.

In the following example the classes of event are displayed in the order cue, stim:

gurita line -x timepoint -y signal --hue event --hueorder cue stim < fmri.csv

Log scale

--logx
--logy

The distribution of numerical values can be displayed in log (base 10) scale with --logx and --logy.

It only makes sense to log-scale the numerical axis (and not the categorical axis). Therefore, --logx should be used when numerical columns are selected with -x, and conversely, --logy should be used when numerical columns are selected with -y.

For example, the X axis can be plotted in log scale like so:

gurita line -x timepoint -y signal --logx < fmri.csv

Axis range limits

--xlim LOW HIGH
--ylim LOW HIGH

The range of displayed numerical distributions can be restricted with --xlim and --ylim. Each of these flags takes two numerical values as arguments that represent the lower and upper bounds of the range to be displayed.

It only makes sense to range-limit the numerical axis (and not the categorical axis). Therefore, --xlim should be used when numerical columns are selected with -x, and conversely, --ylim should be used when numerical columns are selected with -y.

For example, you can display range-limited range for the timepoint column like so:

gurita line -x timepoint -y signal --xlim 5 15.5 < fmri.csv

Facets

--frow COLUMN
--fcol COLUMN
--fcolwrap INT

Line plots can be further divided into facets, generating a matrix of line plots, where a numerical value is further categorised by up to 2 more categorical columns.

See the facet documentation for more information on this feature.

The following command creates a faceted line plot where the event column is used to determine the facet columns:

gurita line -x timepoint -y signal --fcol event < fmri.csv