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Expression in arrays to get a scalar one. Matlab

I have a vector array that contains Time values in an asceding order. With relational expressions I can obtain subset values from that array, after that I need the first value of that subset without creating new variables. For example. Time is an column vector, then I can use Time(something==X) to get a subset values of Time, but then I need the first value of Time(something==X), I can't use Time(something==X)(1) like some programming languages u.u

Solution

  • Unfortunately with MATLAB you need to use temporary variables. It doesn't support this kind of indexing, though it is quite natural and I would love if they supported it.

    You would have to do this: 

    x = Time(something==X);
y = x(1);

    Octave does have the ability of doing this kind of indexing though. The only way I can think of you escaping this is if you use cell arrays. However, if you want to use a normal vector, then you're SOL.

    EDIT: May 13th, 2014 - Referencing David's comment, it is possible to do this without a temporary variable, but readability is very poor. In the end, a temporary variable is still the better way for readability and reproducibility. Check the following SO post that he has referenced: