I did some complecated calculation for cloth simulation. When I get the value from C++ Maple API, it is 1.#QNAN. But when I get the result from Maple, the value is following: (-0.6205772259e-2-0.2125843006e-1*I)*(Pi-1.928059303+5.979053727*I)+0.2356552645e-2*(Pi-1.928059303+5.979053727*I)^2 What is the meaning of 'I' in the result? I am dying to solve the calculation without 1.#QNAN.