how to display / recall data in matlab
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i have such a long code that is really hard to reverse engineer for what i need.
i just need a code that would display which variables that have been used that calculate the matrix.
example:-
A=[10 20 30 40 50]
B= (A.*2)+1 %irreversable code
C=B(B > 40 & B < 80)
C= 41 61 81
D= 20 30 40
to elaborate furthur, i have an array of inputs, 27 elements to be exact, placed into many if conditions
and equations, now i need to know which inputs have passed all my if conditions,(REVERSE ENGINEER)
3 Comments
Rik
on 16 Mar 2019
So you mean you need to deduce which elements from A are still present in D?
It sounds like your code should be better structured to allow for something like this, instead of treating your own code as a black box.
Answers (2)
Rik
on 16 Mar 2019
As long as the input array A has sufficiently unique values, you can use either ismember or ismembertol.
A=[10 20 30 40 50]
blackbox=@(x) x(x*2+1 > 40 & x*2+1 < 80);
D=blackbox(A);
tol=1e-6;%use an absolute tolerance to account for float rounding
L=ismembertol(A,D,tol,'DataScale',1);
%exp(log(3))==3 will return false, ismembertol can account for this
%L contains the positions in A where it shares elements with D
Note that your code example is incorrect, since C would not contain 81, as that is larger than 80, not smaller.
1 Comment
Rik
on 20 Mar 2019
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TADA
on 16 Mar 2019
Seems To Me Like What You Want Is To Keep Track Of All Your If Conditions With A Logical Index
index = B > 40 & B < 80;
% your next conditions go here
index = index & ~isnan(B); % obviously this condition makes no sence, but I'm improvising
C = B(index);
D = A(index);
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