$twoSqrtPi
$twoSqrtPi
ERF(float $lower, float $upper = null) : float|string
ERF.
Returns the error function integrated between the lower and upper bound arguments.
Note: In Excel 2007 or earlier, if you input a negative value for the upper or lower bound arguments, the function would return a #NUM! error. However, in Excel 2010, the function algorithm was improved, so that it can now calculate the function for both positive and negative ranges. PhpSpreadsheet follows Excel 2010 behaviour, and accepts negative arguments.
Excel Function: ERF(lower[,upper])
| float | $lower | lower bound for integrating ERF |
| float | $upper | upper bound for integrating ERF. If omitted, ERF integrates between zero and lower_limit |