loop for matlab array

i have a problem with for loop.we have a vector a=[0 1 1 1 0] and a vector b=[1 1 1 1 1]

 for i = 1:length(a)
     if a(i)==0 
         c = [-1.*b] ;
     else if a(i)==1
         c = [1.* b];
     end
 end

the loop works only for a(1)=0 and stops.

Answer 1

[Geoff Hayes]

Try removing the space between the else if. Re-write this as

 if a(i)==0 
     c = [-1.*b] ;
 elseif a(i)==1
     c = [1.* b];
 end

[best16 programmer]

thank you for your answer,but still does not works,even i removed the space

[Image Analyst]

What are you trying to do? Each iteration you make up a c array which is different on each iteration. c is not a single number you know. It's a vector.

[best16 programmer]

yes i know,i'm trying to display the result c in a edit text

[Image Analyst]

Then just do

handles.edit1.String = sprintf('%d ', c);

This will convert the vector to a string and put it into the edit text box on your GUI.

Answer 2

[Image Analyst]

Maybe you wanted elseif instead of "else if". This works and does several iterations:

a=[0 1 1 1 0]
b=[1 1 1 1 1]

for i = 1:length(a)
  if a(i)==0
    c = [-1.*b]
  elseif a(i)==1
    c = [1.* b]
  end
end

Of course there are better ways to do that and no experienced MATLAB programmer would do that operation like that.

[best16 programmer]

i'm a beginner in matlab.i removed the space but still not working.do you have any suggestions.thanks for advance

[best16 programmer]

the problem is how can we display all the c values in a edit text

[Image Analyst]

They will all be displayed because there is no semicolon at the end of the line. Did you actually try it and look in the command window?

Answer 3

[Andrei Bobrov]

c = (a(:)*2 - 1)*b(:)';

or

c = (a(:)*2 - 1).*b(:);