image_fit

sherpa.astro.ui.image_fit(id=None, newframe=True, tile=True, deleteframes=True)

Display the data, model, and residuals for a data set in the image viewer.

This function displays the data, model (including any instrument response), and the residuals (data - model), for a data set.

The image viewer is automatically started if it is not already open.

Parameters:
  • id (int or str, optional) – The data set. If not given then the default identifier is used, as returned by get_default_id.
  • newframe (bool, optional) – Create a new frame for the data? If False, the default, then the data will be displayed in the current frame.
  • tile (bool, optional) – Should the frames be tiles? If False, the default, then only a single frame is displayed.
  • deleteframes (bool, optional) – Should existing frames be deleted? The default is True.
Raises:

sherpa.utils.err.IdentifierErr – If the data set does not exist or a source expression has not been set.

See also

image_close()
Close the image viewer.
image_data()
Display a data set in the image viewer.
image_model()
Display the model for a data set in the image viewer.
image_open()
Open the image viewer.
image_resid()
Display the residuals (data - model) for a data set in the image viewer.

Notes

Image visualization is optional, and provided by the DS9 application [1].

References

[1]http://ds9.si.edu/site/Home.html

Examples

Display the fit results - that is, the data, model, and residuals - for the default data set.

>>> image_fit()

Do not tile the frames (the three frames are loaded, but only the last displayed, the residuals), and then change the frame being displayed to the second one (the model).

>>> image_fit('img', tile=False)
>>> image_xpaset('frame 2')