How code the following expression into Matlab

[Ein Krieger]

Hey, guys

How can the following equation be entered into matlab:
http://i074.radikal.ru/1304/fe/a8b8e0fccbe5.png

Thakns.

 

[kreil]

That depends on whether P is a matrix of data you have or if you just want to work symbolically.

in general the diff, del2 and gradient operators are used for partial derivatives