minutes for Sept 10, 2025 meeting

Author: DrTimothyAldenDavis

minutes/2025-09-10.md

@@ -0,0 +1,86 @@
+Minutes, Sept 10, 2025
+
+    * LAGraph v1.2.1: released
+    * "vanilla": agreed that if an algorithm cannot be done (or done easily)
+        without GxB extensions in SuiteSparse:GraphBLAS, then it is OK for
+        the vanilla method to return GrB_NOT_IMPLEMENTED.
+        See notes_for_development/000_README_in_development.txt, repeated
+        below.
+
+--------------------------------------------------------------------------------
+
+    consider these methods for src.  Minor revisions needed in some of them,
+    including API revisions:
+
+        LAGr_BreadthFirstSearch_Extended.c: uses LG_:
+            LG_BreadthFirstSearch_SSGrB_Extended.c
+            LG_BreadthFirstSearch_vanilla_Extended.c
+        LAGr_PeerPressureClustering.c
+        LAGraph_AllKCore.c: need both basic & adv methods; this is mixed
+        LAGraph_AllKTruss.c
+        LAGraph_HITS.c
+        LAGraph_Hdip_Fiedler.c: needs lots of polish
+        LAGraph_KCore.c: need both basic & adv
+        LAGraph_KTruss.c
+        LAGraph_MaximalIndependentSet.c: rename LAGr_, need a basic method
+        LAGraph_SquareClustering.c
+        LAGraph_VertexCentrality_Triangle.c
+        LAGraph_coloring_MIS.c
+        LAGraph_coloring_independent_set.c
+        LAGraph_lcc.c
+        LAGraph_cdlp.c: use Container methods
+
+    these need "vanilla" methods, or do we abandon the need for vanilla
+    methods and just require SuiteSparse:GraphBLAS?  Note that
+    SuiteSparse/GraphBLAS.h has "#ifndef GRAPHBLAS_VANILLA" now,
+    so it can be told not to expose and GxB methods in GraphBLAS.h.
+
+        LAGr_EdgeBetweennessCentrality.c
+        LAGr_MarkovClustering.c (but see latest issue posted)
+        LAGr_Modularity.c
+        LAGr_PartitionQuality.c
+        LAGr_SwapEdges.c
+        LAGraph_SwapEdges.c
+        LAGraph_CFL_reachability.c
+        LAGraph_EstimateDiameter.c
+        LAGraph_ExactDiameter.c
+        LAGraph_FastGraphletTransform.c
+        LAGraph_KCoreDecompose.c
+        LAGraph_MultiSourceBFS.c
+        LAGraph_RegularPathQuery.c
+        LAGraph_RichClubCoefficient.c
+        LAGraph_scc.c
+        LG_CC_FastSV5.c
+        LG_CC_FastSV7_FA.c
+
+        suggestion:  if LAGRAPH_VANILLA is true, and a method
+        requires GxB (and we do not have a "vanilla" algorithm),
+        then return GrB_NOT_IMPLEMENTED for the "vanilla" case.
+
+        DECIDED: at Sept 10, 2025 meeting:  the suggestion was accepted
+
+    Algorithms need work:
+
+        LAGr_MaxFlow.c (need to provide output R matrix?  And flow_matrix is
+                expensive to compute; revise)
+        LAGraph_argminmax.c
+        LAGraph_msf.c
+        LAGraph_BF_*.c: need just one variant
+
+    need new LAGraph_Graph enums:
+
+        LAGraph_MaximalMatching.c: need LAGraph_Graph incidence matrix
+        LAGraph_Coarsen_Matching.c: need LAGraph_Graph incidence matrix,
+            and vanilla method
+        LAGr_MaximumMatching.c:  need to switch to Container methods;
+            need LAGraph_Graph bipartite graph, and vanilla method
+        LAGraph_cc_lacc.c: unsure
+
+    do not consider:
+
+        LAGr_PageRankGX.c: for LDBC benchmarks only
+        LAGr_TriangleCount_GPU.c: for testing draft GPU kernels only
+        LAGraph_dnn.c: for an IEEE HPEC Graph Challenge only
+        LAGraph_HelloWorld.c: will always be experimental
+        LAGraph_cdlp_withsort.c: OK, but slow, see LAGraph_cdlp instead
+

notes_for_development/000_README_in_development.txt

@@ -22,7 +22,9 @@ Sept 10, 2025:
         LAGraph_cdlp.c: use Container methods
 
     these need "vanilla" methods, or do we abandon the need for vanilla
-    methods and just require SuiteSparse:GraphBLAS?
+    methods and just require SuiteSparse:GraphBLAS?  Note that
+    SuiteSparse/GraphBLAS.h has "#ifndef GRAPHBLAS_VANILLA" now,
+    so it can be told not to expose and GxB methods in GraphBLAS.h.
 
         LAGr_EdgeBetweennessCentrality.c
         LAGr_MarkovClustering.c (but see latest issue posted)
@@ -42,6 +44,12 @@ Sept 10, 2025:
         LG_CC_FastSV5.c
         LG_CC_FastSV7_FA.c
 
+        suggestion:  if LAGRAPH_VANILLA is true, and a method
+        requires GxB (and we do not have a "vanilla" algorithm),
+        then return GrB_NOT_IMPLEMENTED for the "vanilla" case.
+
+        DECIDED: at Sept 10, 2025 meeting:  the suggestion was accepted
+
     Algorithms need work:
 
         LAGr_MaxFlow.c (need to provide output R matrix?  And flow_matrix is