Math Forum / Math Software / MATLAB / July 2009

Dear Sir
** How can i crop a circle from an image?
** How can i create a push button without border using matlab?
                                                           Thanks

I can take an image and easily threshold it to find the bright spots and count them. In this case they are dyed cells. However the background intensity and dyed cell intensity varies over the area of the images. I need an example of how to locally find the background intensity in ...

i wrote a function for ode23s and what to put a loop in it. the original looks like this:
function ydot=chloride(t,y)
K1=5e7;
K1r=58;

Hopefully this is a simple answer (I'm new to matlab), but how do I create an if/for loop where some of the if conditions are joined? So if I want the if statements to check to see if x>3 AND if y=5 how do I go around doing that? Any help would be great. here's a mock script of ...

I recently upgraded to Matlab 2009a, and I'm having trouble building an XPC Target model. I've tried two different compilers -Visual C++ Express 2008 and Open Watcom 1.8- to build a very simple model, but I get errors in each case:
========================================
Open ...

I have an array A:
A=[1 2 4 5];
I want to add 3 in the third column thus
A=[1 2 3 4 5];

Using set(0,'pointerposition',[x,y]), I can move the mouse cursor around. But can I make it click for real?

I'm twiddling together my first Matlab-GUI with Guide.  Everything
works out nicely so far, but my lack of experience shows.
My routines produce a bitmap image that I want to display in an
axes-control in my GUI.  The tag of the axes-control is "preview_area"

I am trying to export data to a text file, feature.s2p, that is supposed to look like this:
<code># GHZ S RI R 50
31 34
71 78</code>

May I ask why there is an error occur as
"??? Error using ==> optimset
Unrecognized parameter name 'Algorithm'."
when I write the following sentence?

I am trying to retrieve internal function name that is different from
the .m file name, but failed to do it.
For example, I have a .m file named as test.m, and inside the mysum.m,
I have:

I have A and B written in this way
A =
1
1

[NUMERIC,TXT,RAW]=XLSREAD(FILE, RANGE)
If I want the "RANGE" to be the second column, how to write it? thanks.

Just look to modify a figure so that the axis is at a fixed scale. For
example, 100 samples of data equals 25 mm on the screen (used to plot
ECG's).
Thanks!

Are there matlab functions that will:
1. access a web page
2. find a particular field on that web page
3. submit information in that field