if loop on array

i want to use if loop on a array. let say if i have two arrays:

a=[1 2 3 4 5] 
b=[2 3 4 5 6]

now if i want to use if loop such that when any value in array 'a' is 3 and corresponding value in array 'b' is 4,it should print 'ali'.

i tried the following code but it did'nt work.

a=[3 4 3 44 3];
b=[4 3 4 34 26];

    if (any(a==3) & b==4)   
        sprintf('ali')
    end

Answer 1

[Image Analyst]

Your parentheses are not right. Try it this way

a=[3 4 3 44 3];
b=[4 3 4 34 26];
if any(a==3 & b==4)   
    fprintf('ali\n')
end

ali

A=[1 2 5 66 7];
B=[6 4 4 77 8];
% if any element in array A is 5 and the corresponding B element is between 2 and 6
if any(A==5 & B>=2 & B<=6)   
    fprintf('ali')
else
    fprintf('No Matches.\n')
end

ali

[ali hassan]

https://www.mathworks.com/matlabcentral/answers/1644540-if-loop-on-array#answer_893165

@Image Analyst what if i want to know that how many times my first condition is fullfilled or you can say how many times it happened that:

% any element in array A is 5 and the corresponding B element is between 2 and 6

can it be done without using loop?

[Image Analyst]

The conditions are logical variables that can be converted to 0 or 1 when you do math on them. So to count the number of times in the vector where the condition is true, you can use sum

count = sum(A==5 & B>=2 & B<=6)

[ali hassan]

@Image Analyst what if i want it to give logic 1 only if the condition satisfies for 5 times in a row. likewhat i mean is that it continuosly repeat for 5 times.

A=[1 5 5 5 5 5 6];
B=[6 2 5 5 4 3 5];

here only once it is happening that condiition is fulfilled five times in a row.

[ali hassan]

here we have a vector column 'FF_liter_ho_'.If i want to know that how many times non zero values were greater than 770 in a row.

so it happened only once in the column.

[Image Analyst]

@ali hassan if you have the Image Processing Toolbox, you can use regionprops():

ff_liter_ho = [nan, 75, 0, nan, nan, nan, nan, nan, nan, nan, 75, 37, nan, 0, 1, 2, 3, 4]

ff_liter_ho = 1×18

NaN 75 0 NaN NaN NaN NaN NaN NaN NaN 75 37 NaN 0 1 2 3 4

nonZeroIndexes = ff_liter_ho > 0

nonZeroIndexes = 1×18 logical array
   0   1   0   0   0   0   0   0   0   0   1   1   0   0   1   1   1   1

props = regionprops(nonZeroIndexes, 'Area');
numRuns = length(props)

numRuns = 3

runLengths = [props.Area]

runLengths = 1×3

1 2 4

Answer 2

[KSSV]

a=[3 4 3 44 3];
b=[4 3 4 34 26];

if (any(a==3))
    idx = a == 3 ;
    if any(b(idx) == 4 )
        fprintf('ali\n')
    end
end

[KSSV]

@ali hassan commented: https://www.mathworks.com/matlabcentral/answers/1644540-if-loop-on-array#answer_890440

what if i want to give a range of valus? like if a has a value between 3 and 4 and corresponding value of b is between 4 and 5?

[KSSV]

Any example data?

[ali hassan]

assume, i have an array

A=[1 2 5 66 7] and B=[6 4 4 77 8]

i want to put if condition such that if any element in array A is 5 and the corresponding is between 2 and 6, i want to know how many times the condition meets.

[ali hassan]

https://www.mathworks.com/matlabcentral/answers/1644540-if-loop-on-array#comment_1973455

yes this one.