1 files changed, 55 insertions, 0 deletions
diff --git a/pkg/utilities/nttools/lib/invert.x b/pkg/utilities/nttools/lib/invert.x
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+++ b/pkg/utilities/nttools/lib/invert.x
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+
+include <tbset.h>
+
+# INVERT -- Create the complement (inverse) of an array of column pointers
+#
+# B.Simon	20-Oct-87	First Code
+
+procedure invert (tp, numptr, colptr)
+
+pointer	tp		# i:  Table descriptor
+int	numptr		# io: Number of column pointers
+pointer	colptr[ARB]	# io: Array of column pointers
+
+bool	match
+int	numcol, icol, iptr, jptr
+pointer newptr, cp
+
+int	tbpsta(), tbcnum()
+
+begin
+	# Create a temporary array to hold the pointers
+
+	numcol = tbpsta (tp, TBL_NCOLS)
+	call malloc (newptr, numcol, TY_INT)
+
+	jptr = 0
+	do icol = 1, numcol {
+
+	    # Get each pointer in the table and 
+	    # see if it is in the original array
+
+	    cp = tbcnum (tp, icol)
+	    match = false
+	    do iptr = 1, numptr {
+		if (cp == colptr[iptr]) {
+		    match = true
+		    break
+		}
+	    }
+
+	    # If not, add it to the temporary array
+
+	    if (! match) {
+		Memi[newptr+jptr] =  cp
+		jptr = jptr + 1
+	    }
+	}
+
+#	Copy the temporary array to the output array
+
+	numptr = jptr
+	call amovi (Memi[newptr], colptr, numptr)
+	call mfree (newptr, TY_INT)
+
+end