DataPlot

class sherpa.astro.plot.DataPlot[source] [edit on github]

Bases: sherpa.plot.Plot

Create 1D plots of data values.

plot_prefs

The preferences for the plot.

Type:dict
x

The X value for each point (the independent variable).

Type:array_like
y

The Y value for each point (the dependent variable).

Type:array_like
xerr

The half-width of each X “bin”, if set.

Type:array_like
yerr

The error on the Y value, if set.

Type:array_like
xlabel, ylabel, title

Plot labels.

Type:str

Examples

Plot up an example dataset. The default appearance is to draw a symbol at each point, but no line connecting the points (the actual choice depends on the plot backend):

>>> from sherpa.data import Data1D
>>> from sherpa.plot import DataPlot
>>> data = Data1D('a dataset', [10, 20, 25], [2, -7, 4])
>>> dplot = DataPlot()
>>> dplot.prepare(data)
>>> dplot.plot()

The plot attributes can be changed to adjust the appearance of the plot, and the data re-drawn. The following also shows how the plot preferences can be over-ridden to turn off the points and draw a dotted line connecting the points (this assumes that the Matplotlib backend is in use):

>>> dplot.xlabel = 'length'
>>> dplot.ylabel = 'data values'
>>> dplot.plot(marker=' ', linestyle='dashed')

Attributes Summary

plot_prefs

Methods Summary

hline(y[, xmin, xmax, linecolor, linestyle, …]) Draw a line at constant y, extending over the plot.
overplot(*args, **kwargs) Add the data to an existing plot.
plot([overplot, clearwindow]) Plot the data.
prepare(data[, stat]) Create the data to plot
vline(x[, ymin, ymax, linecolor, linestyle, …]) Draw a line at constant x, extending over the plot.

Attributes Documentation

plot_prefs = {}

Methods Documentation

static hline(y, xmin=0, xmax=1, linecolor=None, linestyle=None, linewidth=None, overplot=False, clearwindow=True) [edit on github]

Draw a line at constant y, extending over the plot.

overplot(*args, **kwargs) [edit on github]

Add the data to an existing plot.

This is the same as calling the plot method with overplot set to True.

See also

plot()

plot(overplot=False, clearwindow=True, **kwargs)[source] [edit on github]

Plot the data.

This will plot the data sent to the prepare method.

Parameters:
  • overplot (bool, optional) – If True then add the data to an exsiting plot, otherwise create a new plot.
  • clearwindow (bool, optional) – Should the existing plot area be cleared before creating this new plot (e.g. for multi-panel plots)?
  • **kwargs – These values are passed on to the plot backend, and must match the names of the keys of the object’s plot_prefs dictionary.

See also

prepare(), overplot()

prepare(data, stat=None)[source] [edit on github]

Create the data to plot

Parameters:
  • data – The Sherpa data object to display (it is assumed to be one dimensional).
  • stat (optional) – The Sherpa statistics object to use to add Y error bars if the data has none.

See also

plot()

static vline(x, ymin=0, ymax=1, linecolor=None, linestyle=None, linewidth=None, overplot=False, clearwindow=True) [edit on github]

Draw a line at constant x, extending over the plot.