cbrt() [5/6]

var stan::math::cbrt ( const var &  a )

inline

Returns the cube root of the specified variable (C99).

The derivative is

\(\frac{d}{dx} x^{1/3} = \frac{1}{3 x^{2/3}}\).

\[ \mbox{cbrt}(x) = \begin{cases} \sqrt[3]{x} & \mbox{if } -\infty\leq x \leq \infty \\[6pt] \textrm{NaN} & \mbox{if } x = \textrm{NaN} \end{cases} \]

\[ \frac{\partial\, \mbox{cbrt}(x)}{\partial x} = \begin{cases} \frac{1}{3x^{2/3}} & \mbox{if } -\infty\leq x\leq \infty \\[6pt] \textrm{NaN} & \mbox{if } x = \textrm{NaN} \end{cases} \]

Parameters

a	Specified variable.

Returns

Cube root of the variable.

Definition at line 37 of file cbrt.hpp.