How to use two logical operation inside a if condition?

I have three statements in a if condition and they are executed when the logical operations are true. For example I have two variables a and b, and their values are:

 a=7;
 b=5;
 if a=7 && b=a || b<a
 do something
 end

Can someone please tell me what is the correct way to perform second operation (b=a | | b<a) first, and then do && operation between the result and the first statement (a=7)?

Answer 1

[Star Strider]

They are evaluated left-to right. See the documentation on Logical Operators: Short-Circuit && || (link) for a full discussion.

When in doubt, experiment to understand how the logic works:

a=7;
b=5;
L1 = a==7 && b==a || b<a

a=5;
b=5;
L2 = (b==a || b<a) && a==7 

a=6;
b=5;
L3 = (b==a || b<a) && a==7

... and others as you want to study them.

Also, you need to use ‘double equals’ here:

if a==7 && b==a || b<a

[Asim Ismail]

So it means I have to arrange them like this?

 if b=a || b<a && a=7  
 do something
 end

[Asim Ismail]

Thank you Star Strider, got it

[Star Strider]

My pleasure.

Answer 2

[Image Analyst]

Like this:

a=7;
b=5;
if a==7 && (b==a || b<a)
   % do something
end

Make sure you use double equals for comparison, rather than single equals which does assignment.

Since a has to equal 7, the if won't be true unless b is equal to or less than 7. So you could do this

if  a == 7 && b <= 7

which is the same thing.

[Asim Ismail]

Thanks Image Analyst