Grouping by explicit list

In the most straightforward case, you can use MAKESET to make a single Set out of a group of files listed by name:

% makeset '"im01,im02,im03"' mode=list accept

    MAKESET
    =======
  3 input NDFs accessed using parameter IN

 Set name  Set index   NDF name
 --------  ---------   --------

 im01:
               1       im01
               2       im02
               3       im03

This will write a Set header to each of the named files. As the output shows, the same Set Name attribute ``im01'' (the name of the first file in the list) is given to each, and the Set Index attributes are 1, 2 and 3 respectively.

If you have many files to put into Sets, this may be an unwieldy approach. By using the SETSIZE parameter, an invocation like this can generate many Sets at the same time. If your directory contains the files im01 ... im12 and each group of three in order represents the data from the three CCDs in a mosaic camera, you can write

% makeset 'im*' mode=list setsize=3 accept

    MAKESET
    =======
  6 input NDFs accessed using parameter IN

 Set name  Set index   NDF name
 --------  ---------   --------

 im01:
               1       im01
               2       im02
               3       im03

 im04:
               1       im04
               2       im05
               3       im06

 im07:
               1       im07
               2       im08
               3       im09

 im10:
               1       im10
               2       im11
               3       im12

Care has to be taken with this usage however; it relies on the files being presented to MAKESET in the correct order, which in turn may depend on how your operating system expands wildcards, which is normally alphabetically. If for instance in the above example the files had been named

  im1   im2   im3   im4   im5   im6   im7   im8   im9  im10  im11  im12

(i.e. without the leading zero for numbers less than 10) then they would probably have been presented to MAKESET in the order

 
  im1   im10  im11  im12  im2   im3   im4   im5   im6  im7   im8   im9

which is almost certainly not what you want. If you use MAKESET with wildcards you should be careful to check the logged output to ensure that it has done the right thing.