#NEWLINE# def test_mirror_formula( ) : #NEWLINE# #INDENT# ( u , v , f ) = symbols ( 'u, v, f' ) #NEWLINE# assert ( mirror_formula ( focal_length = f , u = u ) == ( ( f * u ) / ( ( - f ) + u ) ) ) #NEWLINE# assert ( mirror_formula ( focal_length = f , v = v ) == ( ( f * v ) / ( ( - f ) + v ) ) ) #NEWLINE# assert ( mirror_formula ( u = u , v = v ) == ( ( u * u ) / ( u + v ) ) ) #NEWLINE# assert ( mirror_formula ( u = oo , v = v ) == v ) #NEWLINE# assert ( mirror_formula ( u = oo , v = oo ) == oo )