Real nth root of real numbers
Find the real cube root of
ans = -3
For comparison, also calculate
ans = 1.5000 + 2.5981i
The result is the complex cube root of
Create a vector of roots to calculate,
N = [5 3 -1];
nthroot to calculate several real roots of
Y = nthroot(-8,N)
Y = 1×3 -1.5157 -2.0000 -0.1250
The result is a vector of the same size as
Create a matrix of bases,
X, and a matrix of nth roots,
X = [-2 -2 -2; 4 -3 -5]
X = 2×3 -2 -2 -2 4 -3 -5
N = [1 -1 3; 1/2 5 3]
N = 2×3 1.0000 -1.0000 3.0000 0.5000 5.0000 3.0000
Each element in
X corresponds to an element in
Calculate the real nth roots of the elements in
Y = nthroot(X,N)
Y = 2×3 -2.0000 -0.5000 -1.2599 16.0000 -1.2457 -1.7100
Except for the signs (which are treated separately), the result is comparable to
abs(X).^(1./N). By contrast, you can calculate the complex roots using
X— Input array
Input array, specified as a scalar, vector, matrix, or multidimensional
X can be either a scalar or an array of
the same size as
N. The elements of
N— Roots to calculate
Roots to calculate, specified as a scalar or array of the same
X. The elements of
be real. If an element in
X is negative, the corresponding
N must be an odd integer.
power is a more efficient
function for computing the roots of numbers, in cases where both real
and complex roots exist,
power returns only the
complex roots. In these cases, use
nthroot to obtain
the real roots.
This function fully supports tall arrays. For more information, see Tall Arrays.
backgroundPoolor accelerate code with Parallel Computing Toolbox™
This function fully supports thread-based environments. For more information, see Run MATLAB Functions in Thread-Based Environment.
This function fully supports GPU arrays. For more information, see Run MATLAB Functions on a GPU (Parallel Computing Toolbox).
This function fully supports distributed arrays. For more information, see Run MATLAB Functions with Distributed Arrays (Parallel Computing Toolbox).