# Vector Mathematical Functions

This chapter describes Vector Mathematical Functions Library (VML), which is designed to compute mathematical functions on vector arguments. VML is an integral part of the Intel® MKL Kernel Library and the VML terminology is used here for simplicity in discussing this group of functions.

VML includes a set of highly optimized implementations of certain computationally expensive core mathematical functions (power, trigonometric, exponential, hyperbolic etc.) that operate on vectors of real and complex numbers.

Application programs that might significantly improve performance with VML include nonlinear programming software, integrals computation, and many others.

VML functions are divided into the following groups according to the operations they perform:

- VML Mathematical Functions compute values of mathematical functions (such as sine, cosine, exponential, logarithm and so on) on vectors with unit increment indexing.

- VML Pack/Unpack Functions convert to and from vectors with positive increment indexing, vector indexing and mask indexing (see Appendix “Vector Arguments in VML” for details on vector indexing methods).

- VML Service Functions allow the user to set/get the accuracy mode, and set/get the error code.

VML mathematical functions take an input vector as argument, compute values of the respective function element-wise, and return the results in an output vector.