rate_calc

Source: cli/stream/rate_calc.pro

 rate_calc
        Calculate a ratio or other combination from streams of the
        current dataset and add them as new streams.

 Usage:
        rate_calc, index1, index2
   or:
        rate_calc, index

 Arguments:
        index1  int     input   The stream index (or a 1-d array of
                                indices) of the numerator streams. If
                                this index is negative, then user the
                                scalar (which must then be given) as
                                the left operand.
        index2  int     input   The stream index (or a 1-d array of
                                indices) of the denominator streams.
        index   int     input   A 2xN array of pairs of stream
                                indices. (or a stream index or 1-d array of
                                indices if the scalar key is present)

 Keywords:
        ratio           If set, then form the ratio of the 2 streams (default
                        action).
        difference      If set, then form the difference between the streams.
        product         If set, then form the product of the 2 streams.
        sum             If set, then form the sum of the 2 streams
        power           If set, then raise a stream to a power.
        inverse         If set, then form the inverse of the first
                        stream (the second stream is ignored).
        operation string The symbolic operation to perform.
        scalar  any     input   If this keyword is present, then the
                                second stream is ignored and the
                                supplied scalar value is used, on the
                                right of the operand.

 Notes:
        Only one type of operation can be applied for each
        invocation.
        To apply an operation of the form (scalar) (op) (stream),
        specify the first stream as -1 and give the index as the
        second stream.

 Datasets:
        RATE

 History:
        Original: 30/8/00; SJT
        Extend to allow all the new operations: 29/6/01; SJT
        Update for new framework: 15/4/02; SJT
        Renamed: 7/5/02