Help with adding a variable to 'else, if' statements please

Using Arduino Programming Questions
12

I'll add, that's why a lot of people like to do:

  if(0 == desired && hallTemp <setPoint - hysteresis)

Because if you forget the second '=', you wind up with an assignment to a literal rather than a variable, which the compiler will catch. Thusly, completely avoiding the problem in the first place.