operator-() [13/18]

var stan::math::operator- ( const var &  a, const var &  b  )

inline

Subtraction operator for variables.

The partial derivatives are defined by

$\frac{\partial}{\partial x} (x-y) = 1$, and

$\frac{\partial}{\partial y} (x-y) = -1$.

$$\mbox{operator-}(x, y) = \begin{cases} x-y & \mbox{if } -\infty\leq x, y \leq \infty \\[6pt] \textrm{NaN} & \mbox{if } x = \textrm{NaN or } y = \textrm{NaN} \end{cases}$$

$$\frac{\partial\, \mbox{operator-}(x, y)}{\partial x} = \begin{cases} 1 & \mbox{if } -\infty\leq x, y \leq \infty \\[6pt] \textrm{NaN} & \mbox{if } x = \textrm{NaN or } y = \textrm{NaN} \end{cases}$$

$$\frac{\partial\, \mbox{operator-}(x, y)}{\partial y} = \begin{cases} -1 & \mbox{if } -\infty\leq x, y \leq \infty \\[6pt] \textrm{NaN} & \mbox{if } x = \textrm{NaN or } y = \textrm{NaN} \end{cases}$$

Template Parameters

Var1	value type of a var
Var2	value type of a var

Parameters

a	First variable operand.
b	Second variable operand.

Returns

Variable result of subtracting the second variable from the first.

Definition at line 56 of file operator_subtraction.hpp.