plot_data

Context: plotting

Synopsis

Plot the data values.

Syntax

plot_data(id=None, replot=False, overplot=False, clearwindow=True,
**kwargs)

Examples

Example 1

Plot the data from the default data set:

>>> plot_data()

Example 2

Plot the data from data set 1:

>>> plot_data(1)

Example 3

Plot the data from data set labelled "jet" and then overplot the "core" data set. The `set_xlog` command is used to select a logarithmic scale for the X axis.

>>> set_xlog("data")
>>> plot_data("jet")
>>> plot_data("core", overplot=True)

Example 4

The following example requires that the Matplotlib backend is selected, and uses a Matplotlib function to create a subplot (in this case one filling the bottom half of the plot area) and then calls `plot_data` with the `clearwindow` argument set to `False` to use this subplot. If the `clearwindow` argument had not been used then the plot area would have been cleared and the plot would have filled the area.

>>> plt.subplot(2, 1, 2)
>>> plot_data(clearwindow=False)

Example 5

Additional arguments can be given that are passed to the plot backend: the supported arguments match the keywords of the dictionary returned by `get_data_plot_prefs` . Examples include (for the Matplotlib backend): adding a "cap" to the error bars:

>>> plot_data(capsize=4)

changing the symbol to a square:

>>> plot_data(marker='s')

using a dotted line to connect the points:

>>> plot_data(linestyle='dotted')

and plotting multiple data sets on the same plot, using a log scale for the Y axis, setting the alpha transparency for each plot, and explicitly setting the colors of the last two datasets:

>>> plot_data(ylog=True, alpha=0.7)
>>> plot_data(2, overplot=True, alpha=0.7, color='brown')
>>> plot_data(3, overplot=True, alpha=0.7, color='purple')

Example 6

Set the labels used for the X and Y axes for the data. In this example the matplotlib backend is used and so the LaTeX support is used to display an Angstrom symbol as part of the X axis label. Note that the labels will be retained for other plots, including other plot types such as plot_model() or plot_fit_resid().

>>> d = get_data()
>>> d.set_xlabel(r"x axis [$\AA$]")
>>> d.set_ylabel("y axis")
>>> plot_data()

PARAMETERS

The parameters for this function are:

Parameter	Type information	Definition
id	int, str, or None, optional	The data set that provides the data. If not given then the default identifier is used, as returned by `get_default_id` .
replot	bool, optional	Set to True to use the values calculated by the last call to `plot_data` . The default is False .
overplot	bool, optional	If True then add the data to an existing plot, otherwise create a new plot. The default is False .
clearwindow	bool, optional	Should the existing plot area be cleared before creating this new plot (e.g. for multi-panel plots)?

Notes

The additional arguments supported by `plot_data` are the same as the keywords of the dictionary returned by `get_data_plot_prefs` .

Bugs

See the bugs pages on the Sherpa website for an up-to-date listing of known bugs.