Matlab

Simple problem ...
Hi, I need one of numerous experts around this forum. it's a simple problem so if u can help me .. of give to me some references... Assume a isotropic sensor emiting a time t=0 a frontwave. The radius of detection is R and celerity is c. So tmax = R/c is the time horizon of the problem. Assume a target with... 6 Apr 2010 17:33

kronecker product for characters
I'd like to get the vector: ['0000' ; '0100' ; '1000' ; '1100'; '0001' ; '0101' ; '1001' ; '1101'; '0010' ; '0111' ; '1011' ; '1111'; '0011' ; '0111' ; '1011' ; '1111'] from: I0=['00' ;'01'; '10'; '11'] I0 = 00 01 10 11 It would be really nice if I could just do: kron(I0,I0)) But mat... 6 Apr 2010 18:42

Different runtimes for Log, Log2 and Log10
While profiling one of my programs I noticed that Log10 calculations were taking a relatively long time. I was surprised to find that it was a bit slower than Log2, which in itself was considerably slower than Log. This can be seen here: (source code attached) http://img231.imageshack.us/img231/4461/logtimes.png Fi... 7 Apr 2010 03:30

How do i save rgb2ind image so that ican use it in otherfunction?
On Tue, 06 Apr 2010 14:06:04 -0300, Akash <er.akash_agrawal(a)rediffmail.com> wrote: i=imread('image.jpg') [X,map]=rgb2ind(i,128) Here (LHS), the [] are used to indicate two distinct outputs from rgb2ind. %after convert the image i want store the image in handles.changeimage imshow(x,map) fu... 6 Apr 2010 16:26

fmincon in high-dimensional optimization
Hi, I try to estimate the parameters of a short-term interest rate model (with garch & jump in the process) by using fmincon to optimize my log-likelihood. The total parameters need to estimate is quite large (9 in total). There is also one linear inequality constraint for garch parameters. I supplied gradient and use... 6 Apr 2010 18:42

fopen
Hey guys, So, I want to overwrite some lines in a txt file via fopen. so fid = fopen(myfile, 'w+'); cur_line = fgetl(di); while ischar(cur_line) %if changeable(cur_line) %change it end fclose(fid) however when i open with w+ (to overwrite), fgetl always returns -1. Why? I read the help it says: the line c... 12 Apr 2010 15:53

C API: mxCreateDoubleMatrix() from existing pointer.
Hello all, System info: Ubuntu Linux, kernel version: 2.6.28-18-generic MATLAB 7.6.0.324 (R2008a) I am using the C API to access the MATLAB engine from a C program. I have an existing block of data which I'd like to operate on with the MATLAB engine. I've managed to do this by creating a mxArray via mxCreate... 6 Apr 2010 16:26

specify boundary condition for heat equation
How to specific boundary condition for heat equation that at one side the B.C. takes the form of dU/dt=0? thanks! ... 7 Apr 2010 03:30

how to pick elements from an array to form an new array
Hi! Suppose i have a long array, and a loop will find the index of some elements that meet certain requirement, now how to extract all these elements and let them form a new array? Thanks in advance! ... 6 Apr 2010 14:09

regarding sim power systems
> my error was Error using ==> <a href="error:C:\Program Files\MATLAB\R2007a\toolbox\physmod\powersys\powersys\private\psberror.p,16,1">powersys\private\psberror at 16</a> There is no voltage source, current source, or machine block with a frequency matching the Phasor simulation frequency. Hi, my guess is th... 6 Apr 2010 13:01