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diff --git a/noao/twodspec/multispec/sampline.x b/noao/twodspec/multispec/sampline.x
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+include <mach.h>
+include	"ms.h"
+
+
+# GET_SAMPLE_LINE -- Get the nearest sample line to the given image lines.
+#
+# The nearest sample line to each image line is found an returned
+# as the function value.
+
+int procedure get_sample_line (ms, line)
+
+pointer	ms				# MULTISPEC data structure
+int	line				# Image line
+
+int	sample, midpoint
+
+begin
+	sample = 0
+	midpoint = 0
+
+	repeat {
+	    sample = sample + 1
+	    if (sample < MS_NSAMPLES(ms))
+		midpoint = (LINE(ms, sample) + LINE(ms, sample + 1)) / 2
+	    else if (sample == MS_NSAMPLES(ms))
+		midpoint = MAX_INT
+	    else
+		break
+	} until (line < midpoint)
+
+	return (sample)
+end
+
+
+# GET_SAMPLE_LINES -- Get the sample lines for the given image lines.
+#
+# Image lines in the form of a range array are given.
+# The nearest sample line to each image line is found.  The array of
+# sample lines is returned and the function value is the number of
+# sample lines.
+
+int procedure get_sample_lines (ms, lines, samples)
+
+pointer	ms				# MULTISPEC data structure
+int	lines[ARB]			# Image line range array
+int	samples[ARB]			# Return sample lines
+
+int	nsamples, sample, line, midpoint
+int	get_next_number()
+
+begin
+	nsamples = 0
+	sample = 0
+	midpoint = 0
+	line = 0
+
+	while (get_next_number (lines, line) != EOF) {
+	    repeat {
+	        sample = sample + 1
+	        if (sample < MS_NSAMPLES(ms))
+		    midpoint = (LINE(ms, sample) + LINE(ms, sample + 1)) / 2
+	        else if (sample == MS_NSAMPLES(ms))
+		    midpoint = MAX_INT
+	        else
+		    return (nsamples)
+	    } until (line < midpoint)
+
+	    nsamples = nsamples + 1
+	    samples[nsamples] = sample
+	    line = midpoint - 1
+	}
+	return (nsamples)
+end