# boxcox1p
> Compute a one-parameter [Box-Cox transformation][box-cox-transformation] of `1+x`.
A one-parameter [Box-Cox transformation][box-cox-transformation] is defined as
## Usage
```javascript
var boxcox1p = require( '@stdlib/math/base/special/boxcox1p' );
```
#### boxcox1p( x, lambda )
Computes a one-parameter [Box-Cox transformation][box-cox-transformation] of `1+x`.
```javascript
var v = boxcox1p( 1.0, 2.5 );
// returns ~1.8627
v = boxcox1p( 4.0, 2.5 );
// returns ~21.9607
v = boxcox1p( 10.0, 2.5 );
// returns ~160.1246
v = boxcox1p( 2.0, 0.0 );
// returns ~1.0986
v = boxcox1p( -1.0, 2.5 );
// returns -0.4
v = boxcox1p( 0.0, -1.0 );
// returns 0.0
v = boxcox1p( -1.0, -1.0 );
// returns -Infinity
```
## Examples
```javascript
var incrspace = require( '@stdlib/array/incrspace' );
var boxcox1p = require( '@stdlib/math/base/special/boxcox1p' );
var x = incrspace( -1.0, 10.0, 1.0 );
var l = incrspace( -0.5, 5.0, 0.5 );
var b;
var i;
var j;
for ( i = 0; i < x.length; i++ ) {
for ( j = 0; j < l.length; j++ ) {
b = boxcox1p( x[ i ], l[ j ] );
console.log( 'boxcox1p(%d, %d) = %d', x[ i ], l[ j ], b );
}
}
```
## References
- Box, G. E. P., and D. R. Cox. 1964. "An Analysis of Transformations." _Journal of the Royal Statistical Society. Series B (Methodological)_ 26 (2). \[Royal Statistical Society, Wiley]: 211–52. .
[box-cox-transformation]: https://en.wikipedia.org/wiki/Power_transform#Box-Cox_transformation
