_Added in 4.3_

*$modinv(base, modulus)*

Returns the "inverse modulus":https://en.wikipedia.org/wiki/Modular_multiplicative_inverse for the specified base and modulus.

*Parameters*

base - The base to calculate for.
modulus - The modulus to calculate for.

*Example*

<pre>
//echo -ag The inverse modulus for 2 and 1907 is $modinv(2, 1907)
</pre>