Much faster cumsum operator

tarnold17 · Jul 25, 2019 · 72e9132 · 72e9132
1 parent bd0bf8e
commit 72e9132
Showing 1 changed file with 6 additions and 9 deletions.
diff --git a/@sdpvar/cumsum.m b/@sdpvar/cumsum.m
@@ -2,23 +2,20 @@
 %CUMSUM (overloaded)
 
 if nargin == 1 & min(X.dim)==1
-    B = cumsum(X.basis);
+    X.basis = cumsum(X.basis);     
 else
     if nargin == 1
         I = min(find(X.dim>1));
         if isempty(I)
             I = 1;
         end
-    end
-
-    B = [];
-    for i = 1:length(X.lmi_variables)+1
-        C = reshape(X.basis(:,i),X.dim);
-        C = cumsum(C,I);
-        B = [B C(:)];
+    end    
+    if I == 2
+        X = (tril(ones(size(X,2)))*X')';
+    else
+        X = tril(ones(size(X,1)))*X;
     end
 end
-X.basis = B;
 X.conicinfo = [0 0];
 X.extra.opname = '';
 X = flush(X);