Labview and Matlab for PT

Hahaha!!! The title of this article is not real. Not until someone tell me the concept of shift register did I write labview since I began writing matlab. Today, I spent two hours to know how to do DAQ in labview which I didn't accomplish 3 years ago. The main reason possibly is that labview is my first programming language and I know nothing about programming, so it was difficult for me to do DAQ at that time.

Here is my simple code:

Recently, I have upgraded almost my computers to windows 7 except the computer in my lab. Yesterday, I installed matlab 7.1 on my desktop and found out some errors when running the program, even using the comparable mode provided by windows 7. So I find the solution on the internet and here is the solution.

The original article is from this: How To Run Matlab 7.1 On Windows 7

Instructions

1. Right Click On Desktop, choose Personalize
2. Got to Basic and High Contrast Themes tab, and click Window Classic
3. Now, Run matlab
4. Finish

Yesterday night, one of junior classmates told me that he found a useful function called "ginput" which can make the thing getting mouse position easier than using "get(gca......)". It's very convenient when designing some program such as calculating angle in coordinate plane. So, here is a very simple example about how to calculate the angle in a certain image.

global flag h_im h_1
filename='D:\07020203_mpg2-0000281.jpg';
im=imread(filename);
h_im=image(im);
while 1
    cal_cord_ang;
end

function cal_cord_ang
global flag h_im h_1
cla(h_im)
[x,y] = ginput(1);
a=[x,y];
x0=a(1,1);
y0=a(1,2);
hold on
h_1=plot(x0,y0,'color','r','marker','+');
[x,y] = ginput(1);
b=[x,y];
x1=b(1,1);
y1=b(1,2);
h_1=plot([x0 x1],[y0 y1],'color','r','marker','+');
[x,y] = ginput(1);
c=[x,y];
x2=c(1,1);
y2=c(1,2);
h_1=plot([x0 x1 x2],[y0 y1 y2],'color','r','marker','+');

% calculate angle by using this formula --> A dot B = ABcos
A=a-b;
B=c-b;
angle=acosd(dot(A,B)/(norm(A)*norm(B)));
x_t=mean([x0 x2]);
y_t=mean([y0 y2]);
text(x_t,y_t,num2str(angle),'color','r')
ginput(1)
cla(h_im)

However, I almost forget the concept of vector, even the product of two vectors. You can review the concept in this url: http://www.euclideanspace.com/maths/algebra/vectors/angleBetween/index.htm.

Try it, it's very funny!!!

This article, 35 Complete GUI Examples, gives examples about GUI that I found today. It contains several questions that many people usually ask and also attaches the example codes. It is very useful reference when designing a GUI program.