From 10b2692149bc30c35618e18e6e69f08b064ee71f Mon Sep 17 00:00:00 2001
From: Travis Askham <askhamwhat@gmail.com>
Date: Wed, 29 May 2024 10:34:30 -0400
Subject: [PATCH] fixes small bug in chunkermat, working toward speeding up
 chunkermatapply

---
 chunkie/chunkermat.m                |  2 +-
 chunkie/chunkermatapply.m           | 17 +++++------------
 devtools/test/chunkermatapplyTest.m |  8 ++++----
 3 files changed, 10 insertions(+), 17 deletions(-)

diff --git a/chunkie/chunkermat.m b/chunkie/chunkermat.m
index 79f2fa5..fd6d5a8 100644
--- a/chunkie/chunkermat.m
+++ b/chunkie/chunkermat.m
@@ -256,7 +256,7 @@
     chnkri = chnkrs(i);
     for j = 1:nchunkers
         chnkrj = chnkrs(j);
-        if (chnkri.nch < 1 || chnkri.k < 1 || chnkrj.nch<1 || chnkri.k<1)
+        if (chnkri.nch < 1 || chnkri.k < 1 || chnkrj.nch<1 || chnkrj.k<1)
             sysmat_tmp = [];
             break
         end
diff --git a/chunkie/chunkermatapply.m b/chunkie/chunkermatapply.m
index 8b91580..517c260 100644
--- a/chunkie/chunkermatapply.m
+++ b/chunkie/chunkermatapply.m
@@ -1,7 +1,7 @@
-function u = chunkermatapply(chnkr,kern,dval,dens,cormat,opts)
+function u = chunkermatapply(chnkr,kern,dens,cormat,opts)
 %CHUNKERMATAPPLY - apply chunkermat system on chunker defined by kern
 %
-% Syntax:  u = chunkermatapply(chnkr,kern,dval,dens,sigma,opts)
+% Syntax:  u = chunkermatapply(chnkr,kern,dens,sigma,opts)
 %
 % Input:
 %   chnkobj - chunker object describing boundary
@@ -14,13 +14,6 @@
 %                ptinfo.n - unit normals (2,:)
 %                ptinfo.d2 - second derivative in underlying
 %                     parameterization (2,:)
-%   dval - (default 0.0) float or float array. Let A be the matrix 
-%           corresponding to on-curve convolution with the provided kernel. 
-%           If a scalar is provided, the system matrix is 
-%                   A + dval*eye(size(A))  
-%           If a vector is provided, it should be length size(A,1). The
-%           system matrix is then
-%                   A + diag(dval)
 %   dens - density on boundary, should have size opdims(2) x k x nch
 %          where k = chnkr.k, nch = chnkr.nch, where opdims is the 
 %           size of kern for a single src,targ pair
@@ -120,10 +113,10 @@
     error(msg);
 end
     
-if nargin < 5
+if nargin < 4
     cormat = [];
 end
-if nargin < 6
+if nargin < 5
     opts = [];
 end
 
@@ -203,7 +196,7 @@
 
 
 % apply local corrections and diagonal scaling
-u = dval*dens + cormat*dens;
+u = cormat*dens;
 
 % apply smooth quadratures
 if size(kern) == 1
diff --git a/devtools/test/chunkermatapplyTest.m b/devtools/test/chunkermatapplyTest.m
index 211828f..3cd14f4 100644
--- a/devtools/test/chunkermatapplyTest.m
+++ b/devtools/test/chunkermatapplyTest.m
@@ -41,7 +41,7 @@
 udense = sys*dens;
 start = tic; cormat = chunkermat(chnkr,fkern,struct("corrections",true)); 
 toc(start)
-sysapply = @(sigma) chunkermatapply(chnkr,fkern,-0.5,sigma,cormat);
+sysapply = @(sigma) -0.5*sigma + chunkermatapply(chnkr,fkern,sigma,cormat);
 start = tic; u = sysapply(dens); t1 = toc(start);
 
 fprintf('%5.2e s : time for matrix free apply\n',t1)
@@ -89,7 +89,7 @@
 
 udense = sys*bdry_data;
 cormat = chunkermat(chnkr,kerns,struct("corrections",true));
-sysapply = @(sigma) chunkermatapply(chnkr,kerns,eye(2),sigma,cormat);
+sysapply = @(sigma) sigma + chunkermatapply(chnkr,kerns,sigma,cormat);
 
 start = tic; u = sysapply(bdry_data); t1 = toc(start);
 fprintf('%5.2e s : time for matrix free apply\n',t1)
@@ -153,7 +153,7 @@
 
 udense = sys*dens;
 cormat = chunkermat(cgrph,fkern,struct("corrections",true));
-sysapply = @(sigma) chunkermatapply(cgrph,fkern,1,sigma,cormat);
+sysapply = @(sigma) sigma + chunkermatapply(cgrph,fkern,sigma,cormat);
 
 start = tic; u = sysapply(dens); t1 = toc(start);
 fprintf('%5.2e s : time for matrix free apply\n',t1)
@@ -201,7 +201,7 @@
 
 udense = sys*bdry_data;
 cormat = chunkermat(cgrph,kerns,struct("corrections",true));
-sysapply = @(sigma) chunkermatapply(cgrph,kerns,1,sigma,cormat);
+sysapply = @(sigma) sigma + chunkermatapply(cgrph,kerns,sigma,cormat);
 start = tic; u = sysapply(bdry_data); t1 = toc(start);
 fprintf('%5.2e s : time for matrix free apply\n',t1)