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+# Copyright(c) 1986 Association of Universities for Research in Astronomy Inc.
+
+# ARCZ -- Vector reciprocal with checking for zero divisors. If the result
+# of a divide would be undefined a user supplied function is called to get the
+# output pixel value.
+#
+# NOTE: in the interests of simplicity a somewhat arbitrary tolerance is used
+# to check for an undefined divide, i.e., a divide by zero or a divide by a
+# number small enough to cause floating point overflow. A better way to do
+# this would be to provide a machine dependent version of this operator in
+# host$as which catches the hardware exception rather than using a comparison.
+
+procedure arczx (a, b, c, npix, errfcn)
+
+complex a # numerator
+complex b[ARB], c[ARB] # divisor, and output arrays
+int npix # number of pixels
+complex errfcn() # user function, called on divide by zero
+
+int i
+complex divisor
+extern errfcn()
+errchk errfcn
+
+begin
+ if (a == (0.0,0.0)) {
+ call aclrx (c, npix)
+ return
+ }
+
+
+ do i = 1, npix {
+ divisor = b[i]
+ if (divisor == (0.0,0.0))
+ c[i] = errfcn (a)
+ else
+ c[i] = a / divisor
+ }
+end