Doing simple things

With Figaro you can not only look at data that happen to be lying around, you can also process data and thus change the contents of data files. The simplest operations are adding or subtracting a constant, or multiplying or dividing a constant into a data set. These four commands are `icadd', `icsub', `icmult', and `icdiv'.

   ICL> icadd
   IMAGE - (IMage) Name of image to be added to /@a_file/ >
   FACTOR - (FACtor) Additive constant /1/ > 25
   OUTPUT - (OUTput) Name of resulting image > b_file

If you compare the statistics of the old `a_file.sdf' and the new `b_file.sdf', you will find that 25 has been added to each pixel value.

What happens if you give for `output' the same file name as for `image'? In most cases this is possible. You will then not get a second file, but the first file will be modified to contain the new data.

What if you have a spectrum and not an image? Usually that does not matter. When a command asks for the `spectrum' parameter it usually has to be a spectrum. But when it asks for the `image' parameter you can in most cases give a spectrum instead.

You can also use two images as operands instead of an image and a constant. The commands for this are `iadd', `isub', `imult', and `idiv'.

   ICL> idiv
   IMAGE - (IMage) Name of first image /@a_file/ >
   IMAGE1 - (IMAGE1) Name of second image > b_file
   OUTPUT - (OUTput) Name of resulting image > a_file

The first operand is overwritten with the result.