ratio_rate_stream::init

Source: stream/rate/Ratio/ratio_rate_stream__init.pro

 ratio_rate_stream::init
        Constructor for a ratio stream.

 Usage:
        strref = obj_new("ratio_rate_stream", parent, channel, <keys>)

 Argument:
        parent  objref          The reference to the dataset to which
                                the stream is attached.
        Channel string  input   The channel name for the ratio
                                stream.

 Keywords:
        parents pointer input   A 2-element pointer array with the
                                items from which the new stream is to
                                be derived (this can be 2 stream
                                references, a stream reference and a
                                float or a stream reference and an
                                integer).
        name    string  input   A name for the stream.
        operation string input  The operation by which the values were
                                combined 

 History:
        Original: 17/7/00; SJT
        Revise refcount handling: 8/2/01; SJT
        Fix so it works for single-parent streams: 22/5/01; SJT
        Added operation & scalar keys: 21/6/01; SJT
        Added slist keyword: 30/7/01; SJT
        Major reconstruction: 9/4/02; SJT
        Reorder some code to preven undefined variables in
        rate_stream::init: 19/7/02; SJT