2d804382e0be1bb3d7154f650275c7daa14beb4d
jcasper
  Mon Aug 12 07:43:51 2019 -0700
Making a hic error message more helpful, refs #22316

diff --git src/hg/lib/straw/straw.cpp src/hg/lib/straw/straw.cpp
index 4626f37..9054889 100644
--- src/hg/lib/straw/straw.cpp
+++ src/hg/lib/straw/straw.cpp
@@ -141,31 +141,34 @@
       if (c1pos1 == -100) {
 	c1pos1 = 0;
 	c1pos2 = length;
       }
     }
     if (name==chr2) {
       found2=true;
       chr2ind = i;
       if (c2pos1 == -100) {
 	c2pos1 = 0;
 	c2pos2 = length;
       }
     }
   }
   if (!found1 || !found2) {
-    throw strawException("One of the chromosomes wasn't found in the file. Check that the chromosome name matches the genome.");
+    if (chr1==chr2)
+        throw strawException("Chromosome " + chr1 + " wasn't found in the file. Check that the chromosome name matches the genome.");
+    else
+        throw strawException("Chromosomes " + chr1 + " and/or " + chr2 + " weren't found in the file. Check that the chromosome names match the genome.");
   }
   return master;
 }
 
 // reads the footer from the master pointer location. takes in the chromosomes,
 // norm, unit (BP or FRAG) and resolution or binsize, and sets the file 
 // position of the matrix and the normalization vectors for those chromosomes 
 // at the given normalization and resolution
 void readFooter(istream& fin, long master, int c1, int c2, string norm, string unit, int resolution, long &myFilePos, indexEntry &c1NormEntry, indexEntry &c2NormEntry) {
   int nBytes;
   fin.read((char*)&nBytes, sizeof(int));
   stringstream ss;
   ss << c1 << "_" << c2;
   string key = ss.str();