log1p

Scilab Function
Last update : 25/04/2007

log1p - computes with accuracy the natural logarithm of its argument added by one

### Calling Sequence

  `y=log1p(x)`

### Parameters

- `x` : real scalar, vector or matrix
- `y` : real scalar, vector or matrix

### Description

`logp1(x)` is the "element-wise" log(1+x) function. `y(i,j)=log(1 + x(i,j))` . This function, defined for x > -1, must be used if we want to compute log(1+x) with accuracy for |x| << 1.

### Examples

    format("e",24)
    log(1.001)
    log1p(0.001)
    log(1 + 1.e-7)
    log1p(1.e-7)
    log(1 + 1.e-20)
    log1p(1.e-20)
    format("v") //reset default format

### See Also

`log` ,

### Author

B.P.;