function cosbell

Creates a cosine bell filter. This is defined by: Center position (x, y), inner radius r1, and outer radius r2. Optional keywords are naxis1, naxis2 which determine the size of the array. If not set, the size of the array is determined from global variables.

Syntax
result = cosbell(X, Y, RADIUS1, RADIUS2 [, naxis1=value] [, naxis2 = value])

Arguments

X:   The center of the cosine bell filter in the x-axes

Y:   The center of the cosine bell filter in the y-axes

RADIUS1:   The inner radius where the filter is equal to 1

RADIUS2:   The outer radius where the filter is equal to 0

naxis1=value:   Optional, the size of the resulting array in the first dimension

naxis2=value:   Optional, the size of the resulting array in the second dimension

X:	The center of the cosine bell filter in the x-axes
Y:	The center of the cosine bell filter in the y-axes
RADIUS1:	The inner radius where the filter is equal to 1
RADIUS2:	The outer radius where the filter is equal to 0
naxis1=value:	Optional, the size of the resulting array in the first dimension
naxis2=value:	Optional, the size of the resulting array in the second dimension