Computes the base e natural logarithm of a specified input value.

If x is 0, ln is - $\infty$. If x is not complex and is less than 0, ln is not a number (NaN).

For very small values of x, Natural Logarithm (Arg +1) is more accurate than adding 1 to x then using this node.

x

An input to this operation.

This input supports scalar numbers, arrays or clusters of numbers, and arrays of clusters of numbers.

ln

Result of the operation.

This output assumes the same numeric representation as x. When x is of the form x = a + bi, that is, when x is complex, the following equation defines the natural logarithm ln:
$\mathrm{ln}\left(x\right)=\mathrm{ln}\left(|x|\right)+i\mathrm{arg}\left(x\right)$
where arg( x) is the phase of x over the interval $-\pi <\mathrm{arg}\left(x\right)\le \pi$. In other words, LabVIEW uses the following equation:
$\mathrm{ln}\left(x\right)=\mathrm{ln}\left(\sqrt{{a}^{2}+{b}^{2}}\right)+i\mathrm{arctan}2\left(b,a\right)$