Subscript indices must either be real positive integers or logicals in bsxfun

Hi there,

Had a look at various others posts that include this error message but cannot find what is missing from my code. Feel like I am brute forcing this by as it stands I have

T     19081 x 22 double % Raw Data values 

StdTimedEdit  1 x 22 double % Standard Deviation values for each column

MeanTimedEdit 1 x 22 double % Means for each column

StDIndexFull  19081 x 22 logical % Logical Index for which values I want to run the bxs function on

I am trying to do run a bxsfun to replace values outside 2 standard deviations from the mean for each column with 'NaN', but only on the values that equal 1 in the logical StDIndexFull. Currently it looks as such:

T(bsxfun(@lt, T(T(StdIndexFull)), (MeanTimedEdit + 2*StDsTimedEdit)) ...
& bsxfun(@gt, T(T(StdIndexFull)), (MeanTimedEdit - 2*StDsTimedEdit)))= NaN;

This returns the following error:

Subscript indices must either be real positive integers or logicals.

Any assistance or opinions would be muchly appreciated

Matt

Answer 1

[Guillaume]

As Star said, one of your problem is the use of T to index into itself. That makes no sense, I'm not sure what you intended with that.

In addition, your logic has gone a bit wrong on where to use the logical array. You want to find the values that:

1. are outside the standard deviation (using bsxfun indeed) AND
2. correspond to true in the logical array

This is written as:

(bsxfun(@lt, T, MeanTimedEdit - 2*StDsTimedEdit) | bsxfun(@gt, T, MeanTimedEdit + 2*StDsTimedEdit)) ... %part 1
& StdIndexFull  %part 2

So the replacing is written as:

T((bsxfun(@lt, T, MeanTimedEdit - 2*StDsTimedEdit) | bsxfun(@gt, T, MeanTimedEdit + 2*StDsTimedEdit)) & StdIndexFull) = nan;

[Matthew Zelko]

Thanks for this Guillaume, apart from missing 't' after @gt, this works great!

Apparently I didn't realise the bxsfun could use the Index as a stand alone criteria.

Thanks again to both yourself and Star Strider.

[Guillaume]

Sorry about the typo, now fixed.

No, bsxfun is not using the index as a stand alone criteria. What is happening is that the two bsxfun are generating a logical array telling you which number is outside the standard deviation (step 1). It does not use your index array at all. That step 1 logical array is then combined with your index logical array using normal boolean operation.