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+# Copyright(c) 1986 Association of Universities for Research in Astronomy Inc.
+
+# AMED5 -- Median of five vectors. Each output point M[i] is the median of the
+# five input points A[i],B[i],C[i],D[i],E[i]. The vector min and max are also
+# computed and returned in the A and E vectors. The input vectors are modifed.
+
+procedure amed5d (a, b, c, d, e, m, npix)
+
+double a[ARB], b[ARB] # input vectors
+double c[ARB], d[ARB], e[ARB] # input vectors
+double m[ARB] # output vector (median)
+int npix
+
+int i
+double temp
+define swap {temp=$1;$1=$2;$2=temp}
+
+begin
+ do i = 1, npix {
+ # Move the minimum value to A[i].
+ if (b[i] < a[i])
+ swap (b[i], a[i])
+ if (c[i] < a[i])
+ swap (c[i], a[i])
+ if (d[i] < a[i])
+ swap (d[i], a[i])
+ if (e[i] < a[i])
+ swap (e[i], a[i])
+
+ # Move the maximum value to E[i].
+ if (b[i] > e[i])
+ swap (b[i], e[i])
+ if (c[i] > e[i])
+ swap (c[i], e[i])
+ if (d[i] > e[i])
+ swap (d[i], e[i])
+
+ # Return the median value of the central three points.
+ if (b[i] < c[i]) {
+ if (c[i] < d[i]) # bcd
+ m[i] = c[i]
+ else if (b[i] < d[i]) # bdc
+ m[i] = d[i]
+ else # dbc
+ m[i] = b[i]
+ } else {
+ if (c[i] > d[i]) # dcb
+ m[i] = c[i]
+ else if (b[i] > d[i]) # cdb
+ m[i] = d[i]
+ else # cbd
+ m[i] = b[i]
+ }
+ }
+end