Program GRIDPROBE

Summary

The gridprobe program interpolates/extracts the time series for a specified variable for a specified set of points from a GRIDDED3 input file INFILE, and writes the resulting time series as an M3IO file of type CUSTOM3 or as columns to a (human-readable) ASCII REPORT-file with optional header, or both. Points to be extracted are specified in terms of Lat-Lon coordinates taken from an ASCII POINTS file.
Source code for program gridprobe is available under the GNU GPL License, Version 2, and can be downloaded from the CMAS web site as part of the I/O API distribution tar-ball from this page.

Usage

    setenv  INFILE    <path name for  input gridded file>
    setenv  POINTS    <path name for  input points  file>
    setenv  REPORT    <path name for output ASCII   file> or "NONE"
    setenv  OUTFILE   <path name for output M3IO    file> or "NONE"
    setenv  HEADER    <ASCII header on ${REPORT}? (Y/N) [N]>
    gridprobe [and answer the prompts]
    
where INFILE is the logical name of the input data file, POINTS is the logical name of the ASCII points-file, and REPORT is the logical name of the report file to which the ASCII time series report is printed. INFILE must be of type GRDDED3. POINTS is a list-formatted (blank or comma delimited) ASCII file with up to 256 lines giving the latitude and longitude for the interpolation-points, with one point per line.
The program will prompt you for the starting and ending date and time and the time step for the report period, and the name of the variable to be reported. Default values for the time period are computed from the metadata in the INFILE header, and may be accepted by hitting the RETURN key.
The program will log both the input Lat-Lon coordinates and the corresponding grid-normal coordinates (i.e., 1 + INT(X) = grid-column and 1 + INT(Y) = grid-row):
X_grid = ( X - XORIG ) / XCELL Y_grid = ( Y - YORIG ) / YCELL
of the input points, and also write that information to the REPORT-file, if it is produced.
If you want to run this program in batch mode (from a script), the recommended way to develop the script is to run the program once interactively noting the pattern of responses to prompts which generate the particular analysis you want. The pattern of responses then becomes either a command-input file which is redirected into the program in the script, or becomes a "here-document" fed into the execution.