From fa080de7afc95aa1c19a6e6fc0e0708ced2eadc4 Mon Sep 17 00:00:00 2001
From: Joseph Hunkeler <jhunkeler@gmail.com>
Date: Wed, 8 Jul 2015 20:46:52 -0400
Subject: Initial commit

---
 sys/vops/ak/abavr.x | 36 ++++++++++++++++++++++++++++++++++++
 1 file changed, 36 insertions(+)
 create mode 100644 sys/vops/ak/abavr.x

(limited to 'sys/vops/ak/abavr.x')

diff --git a/sys/vops/ak/abavr.x b/sys/vops/ak/abavr.x
new file mode 100644
index 00000000..3e442d8e
--- /dev/null
+++ b/sys/vops/ak/abavr.x
@@ -0,0 +1,36 @@
+# Copyright(c) 1986 Association of Universities for Research in Astronomy Inc.
+
+# ABAV -- Vector block average.  Each pixel in the output vector is the
+# average of the input vector over a block of pixels.  The input vector must
+# be at least (nblocks * npix_per_block) pixels in length.
+
+procedure abavr (a, b, nblocks, npix_per_block)
+
+real	a[ARB]			# input vector
+real	b[nblocks]		# output vector
+int	nblocks			# number of blocks (pixels in output vector)
+int	npix_per_block		# number of input pixels per block
+
+real	sum, width
+
+int	i, j
+int	block_offset, next_block, block_length
+
+begin
+	block_offset = 1
+	block_length = npix_per_block
+	    width = block_length
+
+	if (block_length <= 1)
+	    call amovr (a[block_offset], b, nblocks)
+	else {
+	    do j = 1, nblocks {
+		next_block = block_offset + block_length
+		sum = 0
+		do i = block_offset, next_block - 1
+		    sum = sum + a[i]
+		b[j] = sum / width
+		block_offset = next_block
+	    }
+	}
+end
-- 
cgit