4.59 ln - Natural Logarithm

Format: ln( $num$ ,base)

Compute the natural logarithm of $num$ .

Example

Example 1: Basic Example

$ more dat1.csv
id,val
1,10
2,2.718281828
3,
4,0
5,1
6,-8
$ mcal c='ln(${val})' a=rsl i=dat1.csv o=rsl1.csv
#END# kgcal a=rsl c=ln(${val}) i=dat1.csv o=rsl1.csv
$ more rsl1.csv
id,val,rsl
1,10,2.302585093
2,2.718281828,0.9999999998
3,,
4,0,
5,1,0
6,-8,