check whether an interval instant belongs to an array of intervals

Hi everbod!

have an array of intervals like this C = {[1.54,2.49], [4.97,5.88], [6.69,7.98], [8.05,8.25],[8.58,9.09], [10.48,10.86], [11.16,12.97], [14.51,15.24],[15.38,15.60], [17.20,17.74], [19.16,22.38], [23.69,23.73],[24.59,25.47], [25.59,26.22], [26.65,29.27]};

I want to check if current intervals instant belongs to this array. Where interval divided into different parts e.g. 1.54 to 2.49 is the first part and so on..How can I make program for this?

for example

A=2;

whether or not belongs to 'C'? Help me please

Answer 1

[Kevin Hellemans]

Hi,

I would use cellfun to loop through the intervals and check in each cell. The function belows takes the cell array C and value A, checks if A is part of C and, returns true/false (tf) and if true, provides the position as optional output.

function [tf, position] = ValueInArray(C,A)
    result = cellfun(@(x) inInterval(x,A),C);
    tf = sum(result) > 0;
    if tf
        position = find(result);
    else
        position = [];
    end
end
function tf = inInterval(interval,val)
    lowerLimit = val >= min(interval);
    upperLimit = val <= max(interval);
    tf = lowerLimit && upperLimit;
end

With the values provided, this is my output:

[tf, position] = ValueInArray(C,A)

tf =

  logical

   1


position =

     1

[Walter Roberson]

    tf = sum(result) > 0;
    if tf
        position = find(result);
    else
        position = [];
    end

can be simplified to

    position = find(result);

provided that C is scalar. (If it is not scalar then your code would fail.)