Documentation

Mathlib.Data.Int.Sqrt

Square root of integers #

This file defines the square root function on integers. Int.sqrt z is the greatest integer r such that r * r ≤ z. If z ≤ 0, then Int.sqrt z = 0.

def Int.sqrt (z : ) :

sqrt z is the square root of an integer z. If z is positive, it returns the largest integer r such that r * r ≤ n. If it is negative, it returns 0. For example, sqrt (-1) = 0, sqrt 1 = 1, sqrt 2 = 1

Equations
Instances For
    theorem Int.sqrt_eq (n : ) :
    Int.sqrt (n * n) = (Int.natAbs n)
    theorem Int.exists_mul_self (x : ) :
    (∃ (n : ), n * n = x) Int.sqrt x * Int.sqrt x = x

    IsSquare can be decided on by checking against the square root.

    Equations