@chapter Expression Evaluation
@c man begin EXPRESSION EVALUATION
-When evaluating an arithemetic expression, Libav uses an internal
+When evaluating an arithmetic expression, Libav uses an internal
formula evaluator, implemented through the @file{libavutil/eval.h}
interface.
@item abs(x)
@item squish(x)
@item gauss(x)
+@item isinf(x)
+Return 1.0 if @var{x} is +/-INFINITY, 0.0 otherwise.
@item isnan(x)
Return 1.0 if @var{x} is NAN, 0.0 otherwise.
@item ld(var)
Allow to load the value of the internal variable with number
-@var{var}, which was previosly stored with st(@var{var}, @var{expr}).
+@var{var}, which was previously stored with st(@var{var}, @var{expr}).
The function returns the loaded value.
@item while(cond, expr)