$<H1>$Help for 'combine' program.$</H1>$
$<PRE>$
Date help created:  12 Jun 1994
Date last updated:  04 Jul 1994
$</PRE>$
'combine' combines two (or possibly more) data files into one
output file, using some combining function.

The input data files must be blocked, and not deflated.

To run the program type

	combine <combine script file>

The combine script file must have the following format:

	input 1 <par file of input data file 1>
	input 2 <par file of input data file 2>
	...
	input <N> <par file of input data file N>
	output <output (combined) data file>
	par <par file of output data file>	! this is optional
	<combining function> <combining arguments>

The list of combining functions can be obtained by typing

	combine help $IREF$functions

***functions

The following are currently the possible combining functions,
listed without their argument(s).

$<UL><LI>$$IREF$gradient	- combines p-type and n-type gradient experiments
$<LI>$$IREF$add		- add two or more data sets
$<LI>$$IREF$subtract	- subtract two data sets$</UL>$

To find more details of these combining functions, type

	combine help <combining function>

for example,

	combine help $IREF$gradient

***gradient

The 'gradient' combining function is used to combine a p-type
and n-type gradient experiment.  The combining must be done on
the raw data, i.e. before any other processing (e.g. Fourier
transform) is done.

The correct syntax in the combining script file is

	gradient <gradient dimension>

and a typical example would be

	input 1 /usr/people/wb104/edl387/edl387_5.bin_p.par
	input 2 /usr/people/wb104/edl387/edl387_5.bin_n.par
	output /usr/people/wb104/edl387/edl387_5.bin
	gradient 2	! 'gradient' dimension is dim. 2

This combines a p-type and an n-type gradient experiment for
which the gradient is done in dimension 2.

***add

The 'add' combining function is used to add from two up to four
data files.

The correct syntax in the combining script file is

	add

and a typical example would be

	input 1 /usr/people/wb104/edl387/edl387_5.spc1.par
	input 2 /usr/people/wb104/edl387/edl387_5.spc2.par
	output /usr/people/wb104/edl387/edl387_5.spc12
	add	! add two input data sets

This adds the two named data sets.

***subtract

The 'subtract' combining function is used to subtract two
data files.

The correct syntax in the combining script file is

	subtract

and a typical example would be

	input 1 /usr/people/wb104/edl387/edl387_5.spc1.par
	input 2 /usr/people/wb104/edl387/edl387_5.spc2.par
	output /usr/people/wb104/edl387/edl387_5.spc12
	subtract	! subtract data set 2 from data set 1

This subtracts the second data file from the first.
