I would like to do if-else in 1 line in matlab but I don't know if MATLAB has this feature.

My C program is: 

x = (d < D0)?20:30;

which is equal to
if (d < D0)
   x = 20;
else
   x = 30;

Please suggest how can I do this for 1 line in matlab??? Thank you very much.

On 4 Dez., 06:15, "Aui " <littlebearproj...@gmail.com> wrote:
> I would like to do if-else in 1 line in matlab but I don't know if MATLAB has this feature.
>
> My C program is:
>
> x = (d < D0)?20:30;
>
> which is equal to
> if (d < D0)
>    x = 20;
> else
>    x = 30;
>
> Please suggest how can I do this for 1 line in matlab??? Thank you very much.

why does everyone wants to make his code unreadable?

if (d < D0) x = 20; else x = 30;end;

or for this special case

x = (d < D0)*10+20;

Thank you Justus. 

Actually, I want to apply on matrix and the code is just for example.

The real one is 

F_mb = G./((D <= 500).*H1);
F_mb = G./((D > 500).*H2);

where D, G, H1 and H2 is matrix with the same size.

I just would like to combine them into a single line. Is that possible.

Well, actually, the above code is that I would like to avoid divided by zeros.

but the above code is still incorrect.

My goal is that I would like to divide G with H only the position that H element is not zeros so that will not produce divided by zero problem.

F_mb = G./((H1 ~= 0).*H1);

but in this case, even H1 is 0, it still divided by zeros.

In this thread you seem to be unclear as to what exactly you want.  Does this do it?


F_mb = H1~=0;
F_mb = G(F_mb)./H1(F_mb)

This *could* be done in one line, but it wouldn't be as efficient.

Hello, Matt Fig,

Thank you. It seems to produce what I want but the dimension of the result matrix change!!!! How can I keep the same dimension?

I applied your code for testing a small size matrix
F_mb = H1~=0;
F_mb = G(F_mb)./H1(F_mb)

-------------------

>> G = [2 2; 4 4];
>> H1 = [0 0; 10 10];
>> F_mb = H1~=0

F_mb =

     0     0
     1     1

>> F_mb = G(F_mb)./H1(F_mb)

F_mb =

    0.4000
    0.4000

------------------

What I expect the result should be
F_mb = 
 2                         2
 0.4000              0.4000

Thank you

Well that does add a little bit of complication doesn't it?

% Data
G = [2 2; 4 4];
H1 = [0 0; 10 10];


% Engine
F_mb = G;
idx = H1~=0;
F_mb(idx) = G(idx)./H1(idx)

Hi Matt Fig,

Thank you so much. That's what I want (but I cannot do it myself ^^).