The function GIissqr returns a value of true if n is the square of a Gaussian integer, and false otherwise.

$\mathrm{with}\left(\mathrm{GaussInt}\right)\:$

$\mathrm{GIissqr}\left(-5+12\mathrm{I}\right)$

$\mathrm{true}$

$\mathrm{GIissqr}\left(7+9\mathrm{I}\right)$

$\mathrm{false}$