MATLAB: How to find values which are in specific range for each rows in matrix…

find

for example…
X = [1 2 3 4 5 6 7 8 9;
     2 3 4 5 6 7 8 9 1;
     3 4 5 6 7 8 9 1 2;
     4 5 6 7 8 9 1 2 3;
     5 6 7 8 9 1 2 3 4];
I want to find values which are bigger than 7 and smaller than 3 in each rows.
And also I have to save the data, index of values.
when I made a code like blew,
for k =1:m
    [row(k) col(k)]=find((X(k,:) > 7) && (X(k,:) < 3));
end
there is an error "Operands to the and && operators must be convertible to logical scalar values."
please… help me

Best Answer

The loop is completely pointless in this case. Plus, once you've fixed the error with &&, if there's more than one value that is in range you'll be trying to assign the vectors returned by find to the scalar values row(k) and col(k) which will error. The logical operator for arrays is & not && (see find array elements that meet a condition and logical operators short circuit)
[row, col] = find(x > 3 & X < 7)
edit: and I presume you meant bigger than 3 and smaller than 7, not bigger than 7 and smaller than 3 as there's no number that can match these two conditions.
edit2: and if you want an answer similar to that of KSSV:
[row, col] = find(X < 7 & X > 3); %or whatever the condition is
indx = accumarray(row, col, [], @(c) {c});
Again, no loop needed
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