# Math Constants

The following math constants are supported in the XSI::MATH namespace:

- PI
- PI2
- Invert2PI
- MilliEPS
- MicroEPS
- NanoEPS
- PicoEPS

## PI

     static const double PI(3.14159265358979323846);

Represents the `PI` constant as a `double`.

## PI2

     static const float PI2((float)PI*2.0f);

Represents the `PI` constant multiplied by `2` as a `float`.

## Invert2PI

     static const float Invert2PI(0.5f/(float)PI);

Represents the `PI` constant inverted as a `float`.

## MilliEPS

     static const float MilliEPS(1.0e-03f);

Represents `0.001` as a float.

## MicroEPS

     static const float MicroEPS(1.0e-06f);

Represents `0.000 001` as a float.

## NanoEPS

     static const float NanoEPS(1.0e-09f);

Represents `0.000 000 001` as a float.

## PicoEPS

     static const float PicoEPS(1.0e-012f);

Represents `0.000 000 000 001` as a float.