arraylib::GaborPatch


Name:
arraylib::GaborPatch - Return a two-dimensional array with Gabor function.
Synopsis:
 
nrows ncols GaborPatch -> [[] .. []]
Description:
 
This function returns a matrix of nrows by ncols, with the amplitudes
of a Gabor function, computed over the range of [x_min,x_max] by [y_min,y_max].
These and other parameters can be set by changing the function's options.

An orientation of 0 RAD results in a vertically oriented Gabor.
An orientation of Pi/2 results in an horizontally oriented Gabor.
Angles are measured counter clockwise from the positive x-axis.

The implementation follows the description given by
N. Petkov and R. Kruizinga Biol.Cybern. 76, 83-97 (1997).

Note that GaborPatch automatically performs a coordinate transformation
from the mathematical x-y plane to the matrix row-column system.

Parameters:
 
nrows: number of rows of the result matrix.
ncols: number of columns of the result matrix.

Options:
 
Options which determine the argument range of the Gabor patch.

x_min doubletype - smallest x coordinate value [-2Pi]
x_max doubletype - largest x coordinate value. [ 2Pi]
y_min doubletype - smallest y coordinate value. [-2Pi]
y_max doubletype - largest y coordinate value. [ 2Pi]

Options which determine the Gabor function:

lambda doubletype - Wavelength of the Gabor in RAD. [ 2Pi]
phase doubletype - Phase of the Gabor in RAD. [ 0.0]
orientation doubletype - Rotation of the Gabor in RAD [ 0.0]
sigma doubletype - Width of the Gaussian envelope. [ Pi]
gamma doubletype - Spatial aspect ratio. [ 1.0]

The options correspond to the status dictionary entries of the
gabor_device. Thus, it is possible to use the option dictionary
of the GaborPatch to set the properties of a gabor device.

References:
Petkov N and Kruizinga P: Biol. Cybern. 76, 83-96 (1997)  
Author:
Marc-Oliver Gewaltig  
SeeAlso: Source:
/home/nest/work/nest-2.14.0/lib/sli/arraylib.sli