Error in program (assignment A(I)=B)

Question

Geovanni Rodriguez Martinez 2015-5-8

0
链接

此问题的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/215728-error-in-program-assignment-a-i-b

编辑： James Tursa 2015-5-8

This is my code

>clc, clear, close
xmax=4;
m = 0;
for ang=0:0.5:360
    m = m + 1;
    if ang<=270
    s(m)=(xmax/2)*(1-cos((2*pi*ang)/(270)));
    else
    s(m)=0;
    end 
end
D = [0:0.5:360];
figure; plot (D,s);
E = [0.5:.5:360];
V=diff(s);
figure; plot (E,V);
F = [1:0.5:360];
A=diff(V);
figure; plot (F,A);
ofs=0.470;
rb=2.0;
rr=0.70;
p=0;
for ang=0:0.5:360
    p =p+1;
    sref(p)=sqrt(((rb(p)+rr(p))^2)-(ofs(p)^2));
    xr(p)=ofs;
    yr(p)=sref(p)+s(m);
    l=diff(s);
    b(p)=atan((xr(p)-l)/(yr(p)));
    Xc(p)=xr(p)-rr*sin(b(p));
    Yc(p)=yr(p)-rr*cos(b(p));
    xc(p)=Xc(p)*cos(ang)+Yc(p)*sin(ang);
    yc(p)=-Xc(p)*sin(ang)+Yc(p)*cos(ang);
end
figure; plot(xc,yc);
>Error
>In an assignment  A(I) = B, the number of elements in B and I must be the same.
>Error in graphscam (line 34)
>    b(p)=atan((xr(p)-l)/(yr(p)));

Can Someone help me? I don't understand. I have MATLAB R2011b

2 个评论
显示无隐藏无

Brendan Hamm 2015-5-8

Format your code using the '{} Code' button

Adam 2015-5-8

在 MATLAB Online 中打开

Have you debugged the code? Finding the cause of errors such as this is trivial if you put breakpoints in and query:

size( p );
size( atan((xr(p)-l)/(yr(p)));

at the relevant points. At a glance they look as though they should both be the same size, but there's no need to be guessing from a block of code when you can just debug and find the answer easily.

请先登录，再进行评论。

请先登录，再回答此问题。

Answer 1

James Tursa 2015-5-8

0
链接

此回答的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/215728-error-in-program-assignment-a-i-b#answer_178394

编辑：James Tursa 2015-5-8

在 MATLAB Online 中打开

To debug, at the command line type the following:

dbstop if error

Then run your code as usual. When the error occurs, you will be at the line of code that caused the problem. Examine the sizes of the variables involved to see what the mismatch is. Then trace back through your code to figure out the problem.

If you want to step through your code in the debugger, click on the dash to the right of a line number in the editor (you can set this on any line with a dash ... not just the line with the error). That should put a red dot on that line, which indicates a break point. When you subsequently run your code, the execution will pause at the breakpoints. This allows you to examine variables etc at the command line. You can also use the "Step" etc buttons at the top to step through your code line by line.