PDE u(r,theta) BC IC pytorch solution ■(f:=θ↦{■(20&0≤θ≤π@&0□( ) π<θ<2π)

┤@pde:=∂^2/(∂r^2 ) u(r,θ)+(∂/∂r u(r,θ))/r+(∂^2/(∂θ^2 )u(r,θ))/r^2

=0@bc:=u(1,θ)={■(20&0≤θ≤π@0&π<θ<2π),u(r,0)=u(r,2π),D_2 (u)(r,0)=D_2 (u)(r,2π)┤ )