show gradient vectors orthogonal to level curves



Dear Jaime ,

> On Seg, 2009-10-26 at 20:40 +0100, Adam Majewski wrote:
>> It is not descibed in help ?
>> Why plot in wxMaxima is related with installation of xmaxima ?
> 
> The manual ... says: ....
You are right. It is well descibed in help ( and I should find it).
Only ploteq is not described in help.

Is it posible to :
- check for needed packages when plotdf is loaded ?
- make a info in installer that xmaxima is not only a gui and needed by 
some packages ?


Regards

Adam