ECH_INIT

Initialise COMMON blocks for a specified instrument combination

Description

If a parameter name has been specified, ask the user which configuration to use. Otherwise use the one which was supplied.

The resulting configuration name is a string which consists of zero or more words separated by slahes. They are converted to upper case and then an attempt is made to interpret the first as the name of a supported instrument. If no match is found, the first instrument defined in the spectrograph parameter file read by ECH_LOAD is assumed or, if ECH_LOAD was not called, the default instrument (UCLES) is used. Having determined the instrument, an attempt is made to interpret the remaining words as names of supported echelles and cameras respectively. If no match is found, the first defined echelle and camera of the instrument are assumed.

Having determined the instrument, echelle and camera, copy the relevant parameters to the ECH_COMMONCOMMON block for use by the rest of the spectrograph model routines.

The result is that simple input such as “31” and “79” can continue to be accepted as it always has, but that it is easy to refer to other instruments, echelles and cameras.

This routine must be called before any of the other spectrograph model routines are called. ECH_LOAD may optionally be called before this routine. If it is not, the only available instrument is UCLES with the 31 and 79 echelles and the LONG camera.

Invocation

CALLECH_INIT (PARAM, CONFIG, STATUS)

Arguments
READ PARAM CHARACTER

Name of program parameter corresponding to the configuration to use. If blank, no parameter is read

READ, WRITE CONFIG CHARACTER

Configuration to use. See description above. Is read if PARAM is blank. Is set to echelle name if PARAM is non-blank

READ, WRITE STATUS INTEGER

Global status value

Bugs

None known.

Authors

C.J. Hirst UCL (ZUVAD::CJH)