Math is a global variable(namespace) for built in constants and functions that are very handy when developing. I will go through the most common ones in this article:
Starting with the most common constant, PI:
Math.PI // 3.141592653589793
To get the absolute difference between numbers without getting a negative number you can use the absolute function that is built in.
console.log(-23 - -22);// -> -1 console.log(Math.abs(-23 - -22));// -> 1 console.log(-23 + 22);// -> -1 console.log(Math.abs(-23 + 22));// -> 1 console.log(-23 - 22); // -45 console.log(Math.abs(-23 - 22)); // 45
Another useful Math function is max which takes a set of arguments and returns the biggest one:
console.log(Math.max(1,5,7,-90,222)); //->222
min does the same but for smallest number:
console.log(Math.min(1,5,7,-90,222)); //->-90
to combine all these 3 functions we can find the absolute difference in range between a set of numbers:
console.log(Math.abs(Math.max(1,5,7,-90,222) - Math.min(1,5,7,-90,222))); //-> 312
Difference between -90 and 222 is 312 and that’s we got. If you are alert you might notice that in this case Math.abs was unnecessary and we would have got 312 regardless..
console.log(Math.max(1,5,7,-90,222) - Math.min(1,5,7,-90,222)); //-> 312
That’s true but what if we swap places with the Min and max?
console.log(Math.min(1,5,7,-90,222) - Math.max(1,5,7,-90,222)); //-> -312
Now you can see the power of Math.abs, if you don’t know for certain on which side of the – the numbers will fall. Math.abs can be very handy tool.
console.log(Math.abs(Math.min(1,5,7,-90,222) - Math.max(1,5,7,-90,222))); //-> 312
Another very common function is Math.random which returns a random number between 0 and 1.
console.log(Math.random()); //-> 0.2222222222
You’ll find a more useful way to use this function in this code snippet how to generate a random number with min and max value without any decimals:
Generate a random number
Some other math functions that can be handy:
Math.sqrt returns the Square root of a number:
console.log(Math.sqrt(100)); //-> 10
The Math.tan() function returns the tangent of a number:
console.log(Math.tan(100)); //-> -0.5872139151569291
The Math.log() function returns the natural logarithm of a number
console.log(Math.log(100)); // -> 4.605170185988092
You can find more of these at https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Math
