How to take a partial derivative



# Hi!
# How can I say maxima to "take the partial derivative, not total
derivative" For example, I define such dependencies: (Potential depends to
position and position changes in time)

depends(V, x)$
depends(x, t)$

(%i3) diff(V,x);
                                      dV
(%o3)                                 --
                                      dx


(%i4) diff(V,t);
                                     dx dV
(%o4)                                -- --
                                     dt dx
(%i5)

# This is the total derivative, which uses chain rule. But some function
which takes the partial derivative
partialdiff(V,t);
# should give 0, because V does not depends on t explicitly. But I couldn't
the name of that function. Is there any? If not, maybe if there is a
function which shows the explicit and implicit dependencies, I can write my
own partialdiff function.
# Have a nice day!
-u?ur-