How to enable function is condition is true and ignore its updates till another condition is true

i need to write this code if input1-input2>5 if condition is true, the output should equal to zero even when input1-input2<5 till input1=input3 then it equal 1 and return to if condition again. in other words if input1-input2>5 is true its update will be ignored till input1=input3

Answer 1

[Bob Thompson]

output = 0;  
if input1 == input3;
    output = 1;
    if input1-input2 > 5;
       output = 0;
    end
end

You can precondition the output however you want, but by nesting the input1-input2 condition inside of the input1=input3 condition it prevents the condition from being considered until input1=input3.

Alternatively, if you want the condition to be based on the output something like the following could work.

if output == 0;
    if input1 == input3;
        output = 1;
    end
elseif output == 1;
    if input1 - input2 > 5;
        output = 0;
    end
end

This will check for the output condition specifically and ignore the inputs unless the output is a certain value. Fair warning that in both of these conditions the output only updates once per loop, assuming you have a loop, and so will not check for input1=input3 and then input1-input2>5. You could copy the input1input2 if condition into the first output=0 condition (following the input1input3 condition) if you needed it to be considered in the same loop.

[rowida said]

the function should be activate only when input1-input2>5 then we check condition to output zero or one

the problem is that input1-input2 will vary and disable function

i need to out zero once input1-input2>5 with no consideration to that condition again till input1=input3 so i need loop to be activate once condition is true and deactivate only when input1=input3 not when condition become false

[Bob Thompson]

Maybe an if while combo then?

if input1-input2>5
    output = 0 % set output to 0 since input1-input2 condition was met
    while input1 ~=input3 % look for input1 = input 3
        % do work here
    end
    output = 1 % Change output to 1 since input1 = input3
end

[rowida said]

the simulink didnt work with while, it is variable step.

[Bob Thompson]

You're going to need to run some kind of variable loop inside your if statement if you want to consider multiple situations where your variables do or don't meet a condition. If you would be willing to post some of your code that you are working with I might be able to help more.