if inside of for loop

I don't know what is wrong with this code. The code works when I don't include the if statement. Any idea?

for i = 1:3
  if rt > 100 & rt < 1000
      average(i) = mean(rt(cue==i))
      dev(i) = std(rt(cue==i))
  end
end

[the cyclist]

You are leaving too much for us to guess at, which makes it difficult for us to help you.

Please describe what you mean by "doesn't work" in more detail. Does the code give an error? If so, tell us the complete error message, and which line it occurs on.

If it does not give an error, but just an unexpected result, tell us the expected and actual result.

In general, it would be better to supply code that we can actually run ourselves (e.g. by supplying the values of rt and cue.)

Answer 1

[Jan]

Or perhaps:

match = (rt > 100 & rt < 1000);
rtx   = rt(match);
cuex  = cue(match);
for i = 1:3
  average(i) = mean(rtx(cuex==i))
  dev(i)     = std(rtx(cuex==i))
end

Note that "if rt > 100 & rt < 1000" is evaluated as:

if all(rt > 100 & rt < 1000) && ~isempty(rt)

[Alejandro Estudillo]

I just modified some bits and works pretty well!

match = (rt > 100 & rt < 1000);
rtx   = rt(match);
cuex  = cue(match);
for i = 1:3
  average(i) = mean(rtx(cuex==i))
  dev(i)     = std(rtx(cuex==i))
end

[Jan]

@Alejandro: Yes, this way a typo. Inside the loop rtx and cuex are needed. I've fixed this in my answer.

Answer 2

[Birdman]

You probably forgot subscripting of rt.

for i = 1:3
  if rt(i) > 100 & rt(i) < 1000
      average(i) = mean(rt(cue==i))
      dev(i) = std(rt(cue==i))
  end
end

[Alejandro Estudillo]

I tried the following code, but it only gives me a couple of values and the first one is 0.

for i = 1:3
if rt(cue==i) > 100 & rt(cue==i) < 1000
average(i) = mean(rt(cue==i))
      dev(i) = std(rt(cue==i))
  end
end

[Birdman]

But again

rt(cue==i)

this will result in an array. You may perhaps do it before the loop and give it subscripted to for loop as

rt=rt(cue==i);
for i=1:3
if rt(i)...