1 files changed, 44 insertions, 0 deletions
diff --git a/noao/twodspec/multispec/armsr.x b/noao/twodspec/multispec/armsr.x
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+++ b/noao/twodspec/multispec/armsr.x
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+# ARMSR -- Compute the rms of an array.
+
+real procedure armsr (a, npoints)
+
+real	a[ARB]				# Return rms of this array
+int	npoints				# Number of points in the array
+
+int	i
+real	avg, rms
+
+begin
+	avg = 0.
+	rms = 0.
+	do i = 1, npoints {
+	    avg = avg + a[i]
+	    rms = rms + a[i] * a[i]
+	}
+	rms = sqrt ((npoints * rms - avg * avg) / (npoints * (npoints - 1)))
+
+	return (rms)
+end
+
+
+# ARMSRR -- Compute the vector rms between two real arrays.
+
+real procedure armsrr (a, b, npoints)
+
+real	a[ARB]				# First array
+real	b[ARB]				# Second array
+int	npoints				# Number of points
+
+int	i
+real	residual, rms
+
+begin
+	rms = 0.
+	do i = 1, npoints {
+	    residual = a[i] - b[i]
+	    rms = rms + residual ** 2
+	}
+	rms = sqrt (rms / npoints)
+
+	return (rms)
+end