Average Rating
User Rating:
Visitors Rating:
My rating:

• Last update: 6 years ago
• Price: Free |
• Operating system: Linux, Mac OS X, Win All, BSD, Solaris
• Publisher: Peter (4 other programs)
See full specifications

Conjugate Gradient Optimizer (Scripts) Publisher's description

This example demonstrates the use of conjgrad.m The main advantage of conjgrad.m is that it takes handles to functions which perform the evaluation of the linear operator and its adjoint

This example demonstrates the use of conjgrad.m
The main advantage of conjgrad.m is that it takes handles to functions which perform the evaluation of the linear operator and its adjoint.

The parameter space can be multidimensional.

Example #1

- matrix inversion generate well conditioned random matrix

N = 128;
[U,S,V]=svd(randn(N));
s=diag(S);
A=U*diag(s+max(s))*V;
b=randn(N,1);

define the operator and its adjoint operator = @(x) A*x;

x0 = zeros(size(b));
res_limit = 1e-4;
max_steps = 100;
plot(log10(Res));

Example #2

- deconvolution

N = 128;

the convolution kernel is two dots. So the forward operator will make a twin-image shifted by 2 pixels.

kernel = zeros(N);
kernel(N/2,N/2) = 1;
kernel(N/2,N/2+2) = 1;
f_kernel = fft2(kernel);
test_image = randn(N);

the adjoint of FFT is iFFT
the adjoint of pointwise multiplication is multiplication by conjugate

operator = @(x) ifft2(f_kernel.*fft2(x));
b = operator(test_image);
x0 = zeros(size(test_image));

res_limit = 1e-2;
max_steps = 100;
plot(log10(Res))

System Requirements:

MATLAB 7.9 (2009b)
Program Release Status: New Release
Program Install Support: Install and Uninstall

Click on a tag to find related softwares

Most Popular

ASK, OOK, FSK, BPSK, QPSK, 8PSK modulation 1.1
ASK, OOK, FSK, BPSK, QPSK, 8PSK modulation contain several functions for digital modulation simulation