-.PP
-.if n \
-hypot(infinity,v) = hypot(v,infinity) = +infinity for all v,
-.if t \
-hypot(\(if,v) = hypot(v,\(if) = +\(if for all v,
-including \*(nn.
-.SH ERROR (due to Roundoff, etc.)
-Below 0.97 \*(ups. Consequently hypot(5.0,12.0)\0=\013.0 exactly;