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# log

Computes the natural log of a numeric type.

## Prototype

function log (
value  : numeric
)

return_val [dimsizes(value)] :  float or double

## Arguments

value

An array of one or more values of any dimension value > 0.0

## Return value

Returns a floating point array dimensioned the same as value.

The return type is floating point if the input is floating point, and double if the input is of type double.

## Description

This function returns the natural logarithm of each element of value. Missing values are ignored.

## Examples

Example 1

f = 3.6
log_f = log(f)
print(log_f)        ; Should be 1.280934
Example 2: Find the cube root of 3112.136 [=x^3]

x = exp( log(3112.136)/3.0 )
print( x )        ; Should be 14.6
Example 3: Solve the following for x: y = 9.328*(0.729-x^3) - 1.8

y = 2.0
x = exp( log(0.729-((y+1.8)/9.328))/3.0 )  ; = 0.685

## Errors

If value < 0.0, nan is returned.

If value = 0.0, -inf is returned.