Function

# vvexpm1

Calculates eˣ-1 for each element in an array of double-precision values.

## Parameters

`parameter 1`

The output array, y.

`parameter 2`

The input array, x.

`parameter 3`

The number of elements in the arrays.

## Discussion

If x is nearly zero, the common expression exp(x)-1.0 will suffer from catastrophic cancellation and the result will have little or no precision. This function provides an alternative means to do this calculation without the risk of significant loss of precision. This function provides high accuracy when x is around zero.

### Array-Oriented Exponential and Logarithmic Functions

`vvexp`

Calculates e raised to the power of each element in an array of double-precision values.

`vvexpf`

Calculates e raised to the power of each element in an array of single-precision values.

`vvexp2`

Calculates 2 raised to the power of each element in an array of double-precision values.

`vvexp2f`

Calculates 2 raised to the power of each element in an array of single-precision values.

`vvexpm1f`

Calculates eˣ-1 for each element in an array of single-precision values.

`vvlog`

Calculates the natural logarithm for each element in an array of double-precision values.

`vvlogf`

Calculates the natural logarithm for each element in an array of single-precision values.

`vvlog1p`

Calculates log(1+x) for each element in an array of double-precision values.

`vvlog1pf`

Calculates log(1+x) for each element in an array of single-precision values.

`vvlog2`

Calculates the base 2 logarithm of each element in an array of double-precision values.

`vvlog2f`

Calculates the base 2 logarithm of each element in an array of single-precision values.

`vvlog10`

Calculates the base 10 logarithm of each element in an array of double-precision values.

`vvlog10f`

Calculates the base 10 logarithm of each element in an array of single-precision values.

`vvlogb`

Calculates the unbiased exponent of each element in an array of double-precision values.

`vvlogbf`

Calculates the unbiased exponent of each element in an array of single-precision values.