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+include	<tbset.h>
+
+# REORDER -- Reorder table rows according to an index array
+#
+# This procedure rearranges the rows of a table according to the contents
+# of an index array. The index array is produced by one of the two table
+# sort routines, tsort1 or tsortm. The algorithm used is taken from Knuth's
+# Sorting and Searching p.595.
+#
+# B.Simon	17-Sept-87	First Code
+# B.Simon	15-Jul-88	Rewritten
+# Phil Hodge	12-Sep-88	Don't include tbtables.h
+
+procedure reorder (tp, nindex, index)
+
+pointer	tp		#  i: Table descriptor
+int	nindex		#  i: Number of indices
+int	index[ARB]	# io: Array of row indices
+#--
+int	idx, jdx, kdx, ndx
+int	tbpsta()
+
+errchk	tbrcpy
+
+begin
+	# Use the row after the end of the table for temporary storage
+
+	ndx = tbpsta (tp, TBL_NROWS) + 1
+
+	# Loop over all rows of the table, moving them into their proper
+	# order
+
+	do idx = 1, nindex {
+
+	    # The index array forms one or more cycles. Move the first
+	    # row in the cycle to the temporary location. Repeatedly
+	    # move the remaining rows in the cycle until the final
+	    # location of the first row is found. Move the first row
+	    # from its temporary location to its final location. Update
+	    # the index array to indicate which rows have been moved.
+
+	    if (index[idx] != idx) {
+		call tbrcpy (tp, tp, idx, ndx)
+		jdx = idx
+		while (index[jdx] != idx) {
+		    kdx = index[jdx]
+		    call tbrcpy (tp, tp, kdx, jdx)
+		    index[jdx] = jdx
+		    jdx = kdx
+		}
+		call tbrcpy (tp, tp, ndx, jdx)
+		index[jdx] = jdx
+	    }
+
+	}
+
+	# Remove the temporary row
+
+	call tbrdel (tp, ndx, ndx)
+end