# math

## Mathematical functions.

This module provides an interface to a number of mathematical functions.

## Note!

Not all functions are provided on all platforms. In particular, the `erf/1` and `erfc/1` functions are not provided on Windows.

### acos(X) -> float()

• `X = number()`

### acosh(X) -> float()

• `X = number()`

### asin(X) -> float()

• `X = number()`

### asinh(X) -> float()

• `X = number()`

### atan(X) -> float()

• `X = number()`

### atan2(Y, X) -> float()

• `Y = X = number()`

### atanh(X) -> float()

• `X = number()`

### cos(X) -> float()

• `X = number()`

### cosh(X) -> float()

• `X = number()`

### exp(X) -> float()

• `X = number()`

### log(X) -> float()

• `X = number()`

### log10(X) -> float()

• `X = number()`

### log2(X) -> float()

• `X = number()`

### pow(X, Y) -> float()

• `X = Y = number()`

### sin(X) -> float()

• `X = number()`

### sinh(X) -> float()

• `X = number()`

### sqrt(X) -> float()

• `X = number()`

### tan(X) -> float()

• `X = number()`

### tanh(X) -> float()

• `X = number()`

A collection of mathematical functions that return floats. Arguments are numbers.

### erf(X) -> float()

• `X = number()`

Returns the error function of `X`, where:

`erf(X) = 2/sqrt(pi)*integral from 0 to X of exp(-t*t) dt.`

### erfc(X) -> float()

• `X = number()`

`erfc(X)` returns `1.0` - `erf(X)`, computed by methods that avoid cancellation for large `X`.

### pi() -> float()

A useful number.

#### Limitations

As these are the C library, the same limitations apply.