207194e06b99eef7caf1090af4fdd78c6fd08d0a
braney
  Fri Sep 22 14:04:54 2017 -0700
support custom tracks in collections

diff --git src/hg/lib/mathWig.c src/hg/lib/mathWig.c
index b596b33..761719c 100644
--- src/hg/lib/mathWig.c
+++ src/hg/lib/mathWig.c
@@ -48,30 +48,32 @@
 char *words[100];
 int count = chopByWhite(equation, words, sizeof(words)/sizeof(char *));
 int jj,ii;
 unsigned width = winEnd - winStart;
 struct lm *lm = lmInit(0);
 double *data = needHugeMem(width * sizeof(double));
 bzero(data, width * sizeof(double));
 struct opcodeStack opcodeStack;
 bzero(&opcodeStack, sizeof opcodeStack);
 
 boolean firstTime = TRUE;
 for (jj=0; jj < count; jj++)
     {
     if (pushOpcode(&opcodeStack, words[jj]))
         continue;
+    if (startsWith("$", words[jj]))  // ignore native tracks for the moment
+        continue;
     struct bbiFile *bwf = bigWigFileOpen(words[jj]);
 
     struct bbiInterval *iv, *ivList = bigWigIntervalQuery(bwf, chrom, winStart, winEnd, lm);
 
     if (firstTime)
         {
         for (iv = ivList; iv != NULL; iv = iv->next)
             {
             unsigned start = max(0, iv->start - winStart);
             unsigned end = min(width, iv->end - winStart);
 
             for (ii = start; ii < end; ii++)
                 data[ii] = iv->val;
             }