account negative numbers. Thanks to Nishit Sureshchandra Shah
<nishit@stanford.edu> for the correction.
@item Convert @code{n} to fixed point:
@tab @code{n * f}
-@item Convert @code{x} to integer (rounding down):
+@item Convert @code{x} to integer (rounding toward zero):
@tab @code{x / f}
@item Convert @code{x} to integer (rounding to nearest):
-@tab @code{(x + f / 2) / f}
+@tab @code{(x + f / 2) / f} if @code{x >= 0}, @*
+@code{(x - f / 2) / f} if @code{x <= 0}.
@item Add @code{x} and @code{y}:
@tab @code{x + y}