Hyperbolic {base} | R Documentation

## Hyperbolic Functions

### Description

These functions give the obvious hyperbolic functions. They respectively compute the hyperbolic cosine, sine, tangent, and their inverses, arc-cosine, arc-sine, arc-tangent (or ‘area cosine’, etc).

### Usage

    cosh(x)
    sinh(x)
    tanh(x)
    acosh(x)
    asinh(x)
    atanh(x)

### Arguments

`x` | a numeric or complex vector

### Details

These are internal generic primitive functions: methods can be defined for them individually or via the `Math` group generic.

Branch cuts are consistent with the inverse trigonometric functions `asin` et seq, and agree with those defined in Abramowitz and Stegun, figure 4.7, page 86. The behaviour actually on the cuts follows the C99 standard which requires continuity coming round the endpoint in a counter-clockwise direction.

### S4 methods

All are S4 generic functions: methods can be defined for them individually or via the `Math` group generic.

### References

Abramowitz, M. and Stegun, I. A. (1972) Handbook of Mathematical Functions. New York: Dover.
Chapter 4. Elementary Transcendental Functions: Logarithmic, Exponential, Circular and Hyperbolic Functions

### See Also

The trigonometric functions, `cos`, `sin`, `tan`, and their inverses `acos`, `asin`, `atan`.

The logistic distribution function `plogis` is a shifted version of `tanh()` for numeric `x`.

[Package base version 2.15.2 Index]