ELEMENT_INDEX_STR(A, B) Returns index value in B for each string in A. The string comparisons are case-sensitive.

Example

(See ELEMENT_INDEX) above for a simple example of the numeric case. )

Say we have a dataset that contains a string variable called institute for a collection of stations, and station locations xloc, yloc. Use ELEMENT_INDEX_STR to draw a polygon plot where the data stations belonging to each institute is shown by a dot with a unique color for each institution.

yes? USE obsdata.nc   ! contains a variable called institute

yes? LET inst_names = {“NOAA”, “WHOI”, “FSU”, “BOM”} 
yes? LET code = IS_ELEMENT_STR(institute, inst_names) 

yes? LIST institute, code
      X: 0.5 to 53.5
    Column 1: INSTITUTE
    Column 2: CODE is ELEMENT_INDEX_STR(institute, {“NOAA”, “FSU”, “BOM”, “WHOI”}) 
   INSTITUTE CODE
    1 / 1: “NOAA” 1.000 
    2 / 2: “WHOI” 4.000 
    3 / 3: “FSU” 2.000 
    4 / 4: “BOM” 3.000 
    5 / 5: “NOAA” 1.000 
    6 / 6: “BOM” 3.000 
    ... 
yes? GO basemap X=120:250 Y=25S:65N 20 
yes? GO polymark POLY/OVER/PALETTE=rainbow_by_levels/LEV=(1,5,1) \ xloc, yloc, code, square, 0.2