isNum() function

A simple funtion to decide if the argument is a number.

How does it work?

The function uses a simple if function to check if it is a numerical value. It uses the variable boolean, (value - value == 0) which will return true if value is numerical but false if not. The whole function is:

function isNum(value) {
  if (value - value == 0) {
    return true;
  } else {
    return false;
  };
};

Output

The function is used to output a boolean based upon if value is numerical. If you write the script,

boolean = isNum(25);

boolean will equal true. But if you write the script,

boolean = isNum("25");

boolean will equal false.