PRO test_str_vec, vdata, status, vsize, vtype

; Description: This module tests that the parameter "vdata" contains a one-dimensional vector
;              of strings. In other words, it checks that "vdata" is non-empty, contains data
;              of STRING type, and has exactly one dimension. If the module finds that "vdata"
;              does indeed contain one-dimensional string data, then it also determines the 
;              vector length and saves this information in the parameter "vsize". Finally, the
;              module also returns the IDL type code of the parameter "vdata". 
;
; Input Parameters:
;
;   vdata - ANY - The parameter to be tested whether or not it satisfies the properties that
;                 a one-dimensional vector of string data would have.
;
; Output Parameters:
;
;   status - INTEGER - The parameter "status" is set to "1" if the parameter "vdata" is a
;                      non-empty vector of data of STRING type, with exactly one dimension.
;                      Otherwise, the module sets "status" to a value of "0".
;   vsize - LONG - The length of "vdata". This parameter is only calculated if "status" is set 
;                  to "1".
;   vtype - INTEGER - The IDL type code of the data values stored in "vdata". Note that the IDL 
;                     type code of 7 corresponds to the STRING variable type.
;
; Author: Dan Bramich (dmb@ing.iac.es)
;
; History:
;
;   14/08/2008 - Module created (dmb)

;Determine the IDL type code for "vdata"

;Check that "vdata" has one dimension

;If "vdata" is one-dimensional and contains data of STRING type, then set the value of "status" 
;to "1" and determine the length of "vdata"