blob: 3e442d8e47e3a7f4d126f7191ae068b99cac0952 (
plain) (
blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
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
|
