Home > p2plib > getGlam.m

getGlam

PURPOSE

calc Glam

SYNOPSIS

function Glam=getGlam(p,u,lam,r)

DESCRIPTION

 calc Glam

CROSS-REFERENCE INFORMATION

This function calls:

resi compute residual for -div(c grad u)+au-f-b grad u=0,

This function is called by:

nlooppde newton-loop (with damping parameter alpha) for pde alone,
sgndetA compute sign(detA) from data in p

SOURCE CODE

0001 function Glam=getGlam(p,u,lam,r) 
0002 % calc Glam
0003 if(p.jsw==0 || p.jsw==2) % analyt.
0004   [c,fu,flam]=p.jac(p,u,lam); bc=p.bcf(p,u,lam); c=0; a=0; 
0005   [Gu,Glam]=assempde(bc,p.points,p.edges,p.tria,c,a,-flam); 
0006 else % numerically
0007   del=1e-8; r1=resi(p,u,lam+del);Glam=-(r-r1)/del; 
0008 end
0009