Program: SHUFFLE
Purpose: The programme shuffles profiles in a set so that they are
aligned on positions taken from another set.
Category: ANALYSIS, COMBINATION, MANIPULATION
File: shuffle.c
Author: K.G. Begeman
Keywords:
INSET= Set and subsets of data to be shuffled. Maximum number
of subsets is 128.
CSET= Set and subset which contains the positions of the
profile centres. CSET could be a velocify field created by
MOMENTS or GAUFIT.
NMAX= Number of output subsets to one side of the profile centres.
The total number of output subsets is 2*NMAX+1. Maximum
value for NMAX is 128.
CDELT= Grid separation in units of the output subsets. A default
is calculated from the input subsets. CDELT must be positive.
OUTSET= Set (and subsets) where the shuffled profiles are to be
stored. The number of output subsets is 2*NMAX+1.
Description: With the input data cube and one input velocity field,
SHUFFLE shifts all spectra such that their new origins
correspond to the velocities in the velocity field. These
origins are set to the coordinate 0 in the output set.
The interpolation required along the spectral axis is
done with a simple linear interpolation.
Example: SHUFFLE INSET=n4214 freq-ohel
Set n4214 has 3 axes
RA-NCP from -127 to 128
DEC-NCP from -127 to 128
FREQ-OHEL from 1 to 63
SHUFFLE CSET=n4214vel param 1
Set n4214vfield has 3 axes
RA-NCP from -127 to 128
DEC-NCP from -127 to 128
PARAM-GAUFIT from 1 to 3
SHUFFLE NMAX=32
SHUFFLE CDELT=8
SHUFFLE OUTSET=shuffle
Set shuffle has 3 axes
RA-NCP from -127 to 128
DEC-NCP from -127 to 128
VELO from -32 to 32
SHUFFLE +++ FINISHED +++
Notes: In general the axes names of the output set will be the
same as the ais names of the input set, except for
frequency axis with velocity information. In these cases
the axis name will be converted to VELO.
Updates: Jul 15, 1992: KGB, Document created.
Mar 09, 2000: JMH, increased NMAX to 128