Return a number equal to the specified value (except for possible rounding) having the exponent equal to the exponent of the specified exponent. Rounding may occur when the exponent is greater than the quantum of value. E.g., quantize(147e-2_d32, 1e-1_d32) yields 15e-1_d32. In the opposite direction, if exponent is sufficiently less than the quantum of value, it may not be possible to construct the requested result, and if so, NaN is returned. E.g., quantize(1234567e0_d32, 1e-1_d32) returns NaN.