How do I create bin widths using a simple algebra function?

I have currently created a single bin for my vector time(0-5million years) using :

ExtractedData = data(find(time<5),2);

On this bin I have removed the NaN values and calculated the mean and SD. I need to repeat these calculations for bins which are 5-10million years, 10-15millionyears...etc until 540million years. I've been instructed to do this by creating a loop e.g.

for n=1:108

ExtractedData = data(find(time<5),2);

%%%code to remove NaN

%%%code to calculate mean and SD etc

end

and to change the part of the function "time<5" with a function for a maximum and minimum value of time where the minimum is defined by the function 5(n-1) and the maximum defined by 5(n-1)+5.

I was wandering how I can incorporate this into the line of code starting with "ExtractedData"?

Thanks

Charlie

Answer 1

[Massimo Zanetti]

IMPORTANT: there is no need to use find!!!

EXPLOIT MATLAB LOGICAL INDEXING

To replace "time<5" with "5<time<10" just use & (and operator) to match the cases where both 5<time AND time<10:

data( (5<time)&(time<10) ,2);

[Charlie Finnie]

okay, thank you. DO you know how to replace "5<time" with a function that will give me values of time which follow the algebra function 5n+1?

[Massimo Zanetti]

for an index k, it is k=5n+1 for some n if k-1 is divisible by 5, so

 data( rem(time-1,5)==0 ,2);

Of course, this only works if time is vector of integers.

Answer 2

[Steven Lord]

Rather than building the bins yourself, I recommend using the approach I described in one of your other questions that uses discretize.

[Massimo Zanetti]

Steven, the author of question in the link you posted is the same as here.. so I think he is really interested in knowing how to bin using another approach..

[Charlie Finnie]

Hi, yeah I need to create the bins manually (not using discretize) as this is required for the modelling I will be doing on the bins