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Last modified: December 2006

URL: http://cxc.harvard.edu/ciao3.4/pix_get_energy.html
Hardcopy (PDF): A4 | Letter
AHELP for CIAO 3.4 pix_get_energy Context: pixlib

Synopsis

Return the photon energy corresponding to a given grating dispersion (GAC) value.

Syntax

Double_Type pix_get_energy( Double_Type x, Double_Type y )

Description

Calculates the photon energy, in keV, for a given grating position and using the current pixlib settings. The x and y values are in the GAC coordinate system, and so represent the grating dispersion and cross-dispersion angles in degrees. The grating order - as set by pix_set_grating() - must be non-zero for this routine to work.

The pix_get_grating_wavelength() routine can be used to find the wavelength of the photon instead of the energy.

Bugs

See the bugs page for the pixlib library on the CIAO website for an up-to-date listing of known bugs.

Hardcopy (PDF): A4 | Letter
Last modified: December 2006



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