Last modified: December 2023

AHELP for CIAO 4.16 Sherpa


Context: visualization


Create a contour plot for an image data set.


contour(*args, **kwargs)


Create one or more contour plots, depending on the arguments it is set: a plot type, followed by an optional data set identifier, and this can be repeated. If no data set identifier is given for a plot type, the default identifier - as returned by `get_default_id` - is used. This is for 2D data sets.


Example 1

>>> contour('data')

Example 2

>>> contour('data', 1, 'data', 2)

Example 3

>>> contour('data', 'model')

Example 4

>>> contour('data', 'model', 'fit', 'resid')

Example 5

>>> contour('data', 'model', alpha=0.7)


The supported plot types depend on the data set type, and include the following list. There are also individual functions, with contour_ prepended to the plot type, such as `contour_data` and the `contour_fit_resid` variant:

Item Definition
data The data.
fit Contours of the data and the source model.
fit_resid Two plots: the first is the contours of the data and the source model and the second is the residuals.
kernel The kernel.
model The source model including any PSF convolution set by `set_psf` .
psf The PSF.
ratio Contours of the ratio image, formed by dividing the data by the model.
resid Contours of the residual image, formed by subtracting the model from the data.
source The source model (without any PSF convolution set by `set_psf` ).

The keyword arguments are sent to each plot (so care must be taken to ensure they are valid for all plots).

Changes in CIAO

Changed in CIAO 4.13

Keyword arguments, such as alpha, can be sent to each plot.


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

See Also

copy_data, dataspace1d, dataspace2d, datastack, delete_data, fake, get_axes, get_bkg_chisqr_plot, get_bkg_delchi_plot, get_bkg_fit_plot, get_bkg_model_plot, get_bkg_plot, get_bkg_ratio_plot, get_bkg_resid_plot, get_bkg_source_plot, get_counts, get_data, get_data_contour, get_data_contour_prefs, get_data_image, get_data_plot, get_data_plot_prefs, get_dep, get_dims, get_error, get_quality, get_specresp, get_staterror, get_syserror, group, group_adapt, group_adapt_snr, group_bins, group_counts, group_snr, group_width, load_ascii, load_data, load_grouping, load_image, load_quality, pack_image, set_data, set_quality, ungroup, unpack_ascii, unpack_data, unpack_image
get_filter, load_filter, set_filter
get_default_id, list_data_ids, list_response_ids
clean, image_model, image_model_component, image_source, image_source_component
plot_data, set_xlinear, set_xlog, set_ylinear, set_ylog
contour_kernel, contour_psf, image_kernel
save_error, save_filter, save_grouping, save_quality, save_staterror, save_syserror
calc_data_sum, calc_data_sum2d, calc_ftest, calc_kcorr, calc_mlr, calc_model_sum2d, calc_source_sum2d, get_rate
contour_data, contour_fit, contour_fit_resid, contour_model, contour_ratio, contour_resid, contour_source, histogram1d, histogram2d, image_close, image_data, image_deleteframes, image_fit, image_getregion, image_open, image_ratio, image_resid, image_setregion, image_xpaget, image_xpaset, rebin