Error Accessing Index - Told index must be positive or logical, however it is both...

I am using a forloop to pull out values of one vector based on indecies specified by a second vector. My trial array is 500x6 and my events vector is 4x1 of two decimal numbers (i.e - 1.23, 3.42, 4.89). For certain columns in my trial array, I want to reset the start point to 0 and adjust all values in that cycle accordingly Here is what my code looks like

for cycle = 1:(length(events)-1)

    initial_value = trial(events(cycle)*100, 11)

    plot(linspace(0,1,100)*100, (interp1(linspace(0,1,length(trial(events(cycle)*100:events(cycle+1)*100, 11))), (trial(events(cycle)*100:events(cycle+1)*100, 11)-initial_value), linspace(0,1,100))))

end

When I do this, I get this error message:

Attempted to access trial(253,11); index must be a positive integer or logical.

However, my trial file does indeed contain the index 253, 11. Any ideas why I am getting this error?

Answer 1

[Andreas Goser]

Maybe it is not exactly and integer, like 1.0000001.

[Walter Roberson]

http://matlab.wikia.com/wiki/FAQ#Why_is_0.3_-_0.2_-_0.1_.28or_similar.29_not_equal_to_zero.3F

Answer 2

[Sean de Wolski]

dbstop if error

Then wait until it errors and inspect your variables.

format long

will likely show you that Andreas' is correct.

Answer 3

[Shawn]

I put in a round function on my events variable and it seems to have fixed it. I guess after looking for all the complicated answers I looked right past the simple one! Thank you