Help for a "Surface and Flux integrals" program

[salvomic]

(11-04-2017 12:06 AM)Arno K Wrote:  Checked that by hand, 4 is ok, so my program works like it shall and the only remaining problem is catching an error to provide help, I will think about that, tomorrow as it is late now. But you can skip the '' around the entries, that leaves only the {} around that all and you can provide help...

I saw we can avoid also {}:
sfint(3*x+y,[u,v,u*v],[0,1],[0,2π]) works, like the other form (for flux) with a vector at first place. So the syntax is a bit easier.
For the control, you are right; however already in some cases the Prime complaint with a warning "no control is made for singular points..."

Salvo

EDIT:
also they are correct these examples (you can use also these ones for testing):
sfint(1,[r*COS(u), r*SIN(u), v],[0,2π],[0,L]) -> 2*L*π*|r|, that's the area of a cylinder with radius r and high L
and
sfint([y, -x, z],[r*SIN(u)*COS(v), r*SIN(u)*SIN(v), r*COS(u)],[0,π],[0,2π] ), the Flux of f(x)=yi-xj+zk exiting from a sphere radius 1 centered in the origin, with spheric coordinates in [0,π] x [0,2π] where σ(u,v) = r*sin(u)*cos(v) i + r*sin(u)*sin(v)j+r*cos(u)k
\( \int_{\Sigma }\mathbf{f}\cdot \mathbf{n}=\frac{4}{3}\pi r^3 \)