isnum - Return code telling whether the input string is numerical

       Jessica Mink, SAO (jmink@cfa.harvard.edu)

6 November 2015                                     WCSTools                                            isnum(1)

isnum is a utility for identifying and classifying an input string.  <B>isnum</B> returns an integer code
       depending  on  how  it  identifies  the input number: 0: string is not any sort of number 1: String is an
       integer 2: String is a floating point number 3: String is a hh:mm:ss.ss time 4: String  is  a  yyyy-mm-dd
       date

       isnum - Return code telling whether the input string is numerical

       isnum string