condition

I am a new in Matlab I try to do condition with (if and elseif and else) for a simple arry but the condion equations that I put do not verified array a, what is the problem?

a=1:1:10
for m=1
  for n=1:10
   if a(m,n)<4
     a=a*2
   elseif a(m,n)>4
     a=a*3
   else 
     a=a*4
   end
 end
end

[Paulo Silva]

please format your code, put it inside {}

[Paulo Silva]

please explain what's the purpose of the code you want to do

Answer 1

[bym]

your last condition is dead code, your conditions are either less than 4 or greater than 4, so the last 'else' statement is not used. Also, you do not need the for m= 1 loop. Here is an example:

a = 1:10
for k = 1:10
if a(k)<4
x(k)=a(k)*2;
elseif a(k)<8
x(k)=a(k)*3;
else
x(k) = a(k)*4;
end
end
[a;x]

[Walter Roberson]

Unless the question was edited, I believe you have incorrectly determined the final condition to be "dead code". Consider when a(k) is 4 exactly: that is not less than 4, and it is not greater than 4, so the else would be reached and for that one case of a(k)==4 only, the code should multiply by 4.

Your code, though, would multiply the case of a(k)==4 by 3, and would multiply the cases of a(k)==8, a(k)==9, and a(k)==10 by 4 whereas the original code would multiply those cases by 3.

[Walter Roberson]

Would multiply, that is, if the original poster had done the multiplications on a(k) instead of on _all_ of a.

[Paulo Silva]

The OP doesn't seem very interested about his question, no explanation so far, I'm starting to ignore such questions and move on to other questions where the OP explained what he/she wants.

[Jan]

@Paulo: Are the "Op has left the building" threads getting more in the last weeks? Or am I getting tired?

[Paulo Silva]

Jan, just a few more than usual, must be vacations related, what's getting up on my nerves is the ones that post without enough details and expect us to decode what they want.