some comments

Author: oneilm

chunkie/+chnk/+axissymlap2d/g0funcall.m

@@ -4,7 +4,11 @@
 % chnk.axissymlap2d.g0funcall evaluates a collection of axisymmetric Laplace
 % Green's functions, defined by the expression:
 %
-%     gfunc(n) = pi*rp * \int_0^{2\pi} 1/|x - x'| e^(-i n t) dt 
+%     gfunc(n) = pi*rp * \int_0^{2\pi} 1/|x - x'| e^(-i n t) dt
+%
+% it is assumed that x = (x,0,z) otherwise the integral above should pick up a
+% phase factor out front of exp(i*n*phi), where phi is the azimuthal coordinate
+% of x in cylindrical coordinates.
 %
 % The extra factor of rp (and maybe pi?) out front makes subsequent interfacing
 % with RCIP slightly easier. Modes 0 through maxm are returned, with gval(1) =

devtools/test/g0funcallTest.m

@@ -25,6 +25,10 @@
 nq = 2000;
 hhh = 0.000001
 
+% evaluate the kernel using brute force trapezoidal integration, and then
+% compare with the recurrence relation code. Note: The "exact" derivatives are
+% estimated using finite difference, so it is expected that the error is O(h^2)
+
 for m = 1:(maxm+1)
     dint = chnk.axissymlap2d.gkm_brute(r, rp, z, zp, zk, m-1, nq);
     exact(m) = dint*4*pi*pi*rp;