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Reliable integer root function?

Does Sage have an integer_root(x, n) function which reliable (!) returns floor(root(x,n)) for n-th roots? I think that it should be offered as a Sage function if not.

This seems to work:

def integer_root(x, n): return gp('sqrtnint(%d,%d)' %(x,n))

Integer n-th root of x, where x is non-negative integer.

// Related: question 10730.

Reliable integer root function?

Does Sage have an integer_root(x, n) function which reliable (!) returns floor(root(x,n)) for n-th roots? I think that it should be offered as a Sage function if not.

This seems to work:

def integer_root(x, n): return gp('sqrtnint(%d,%d)' %(x,n))

Integer n-th root of x, where x is non-negative integer.

// Related: question 10730.

Edit: The answer of castor below shows a second way to define such a function:

def integer_root(x, n): return ZZ(x).nth_root(n, truncate_mode=1)[0]

Which version will be faster?