1 files changed, 93 insertions, 0 deletions
diff --git a/vendor/cfitsio/iter_image.c b/vendor/cfitsio/iter_image.c
new file mode 100644
index 00000000..43f263cb
--- /dev/null
+++ b/vendor/cfitsio/iter_image.c
@@ -0,0 +1,93 @@
+#include <string.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include "fitsio.h"
+
+/*
+  This program illustrates how to use the CFITSIO iterator function.
+  It reads and modifies the input 'iter_image.fit' image file by setting
+  all the pixel values to zero (DESTROYING THE ORIGINAL IMAGE!!!)
+*/
+main()
+{
+    extern zero_image(); /* external work function is passed to the iterator */
+    fitsfile *fptr;
+    iteratorCol cols[3];  /* structure used by the iterator function */
+    int n_cols;
+    long rows_per_loop, offset;
+
+    int status, nkeys, keypos, hdutype, ii, jj;
+    char filename[]  = "iter_image.fit";     /* name of rate FITS file */
+
+    status = 0; 
+
+    fits_open_file(&fptr, filename, READWRITE, &status); /* open file */
+
+
+    n_cols = 1;
+
+    /* define input column structure members for the iterator function */
+    fits_iter_set_file(&cols[0], fptr);
+    fits_iter_set_iotype(&cols[0], InputOutputCol);
+    fits_iter_set_datatype(&cols[0], 0);
+
+    rows_per_loop = 0;  /* use default optimum number of rows */
+    offset = 0;         /* process all the rows */
+
+    /* apply the rate function to each row of the table */
+    printf("Calling iterator function...%d\n", status);
+
+    fits_iterate_data(n_cols, cols, offset, rows_per_loop,
+                      zero_image, 0L, &status);
+
+    fits_close_file(fptr, &status);      /* all done */
+
+    if (status)
+        fits_report_error(stderr, status);  /* print out error messages */
+
+    return(status);
+}
+/*--------------------------------------------------------------------------*/
+int zero_image(long totalrows, long offset, long firstrow, long nrows,
+             int ncols, iteratorCol *cols, void *user_strct ) 
+
+/*
+   Sample iterator function that calculates the output flux 'rate' column
+   by dividing the input 'counts' by the 'time' column.
+   It also applies a constant deadtime correction factor if the 'deadtime'
+   keyword exists.  Finally, this creates or updates the 'LIVETIME'
+   keyword with the sum of all the individual integration times.
+*/
+{
+    int ii, status = 0;
+
+    /* declare variables static to preserve their values between calls */
+    static int *counts;
+
+    /*--------------------------------------------------------*/
+    /*  Initialization procedures: execute on the first call  */
+    /*--------------------------------------------------------*/
+    if (firstrow == 1)
+    {
+       if (ncols != 1)
+           return(-1);  /* number of columns incorrect */
+
+       /* assign the input pointers to the appropriate arrays and null ptrs*/
+       counts       = (int *)  fits_iter_get_array(&cols[0]);
+    }
+
+    /*--------------------------------------------*/
+    /*  Main loop: process all the rows of data */
+    /*--------------------------------------------*/
+
+    /*  NOTE: 1st element of array is the null pixel value!  */
+    /*  Loop from 1 to nrows, not 0 to nrows - 1.  */
+
+    for (ii = 1; ii <= nrows; ii++)
+    {
+       counts[ii] = 1.;
+    }
+    printf("firstrows, nrows = %d %d\n", firstrow, nrows);
+    
+    return(0);  /* return successful status */
+}