The simplify(expr, zero) calling sequence replaces complex numerics of type embedded_real with their corresponding real parts, and it replaces objects of type embedded_imaginary with their corresponding imaginary parts.

Note:  This routine is not called automatically by the general simplify routine.

$\mathrm{simplify}\left(3+\left(0.+2\mathrm{I}\right)f\left(-1.-0.\mathrm{I}\,x\right)\,\mathrm{zero}\right)$

$3+2.\mathrm{I}f\left(\mathrm{-1.}\,x\right)$