unable to calculate logs in SWARM

[Laurence Clark]

Hi,

I have been having problems using the log10(double) function from with my
SWARM application.  (I'm using SWARM 1.2 under Linux Redhat 5.0)

The following function:

// add an entry to the table
-addEntry:(char *) r result: (char *) r2 rateConstant: (float) c signalSent:
(int) s {
  Reaction * entry;
  entry = [Reaction create: [self getZone]];
  [entry setReaction:r result: (char *) r2 rateConstant:c signalSent:s];
  [ReactionList addLast: entry];
  printf("Reaction: %s => %s added.\n", r, r2);
  if (1.0/c < tSim) tSim=1.0/c;
  printf("rate=%e, log=%e\n", c, log10(c));
  return self;}

yields this output:

Reaction: TT(0)WWAA + asp => asp-TT(0)WWAA added.
rate=6.000000e-07, log=1.753933e-321
Reaction: TT(0)WWAAp + asp => asp-TT(0)WWAAp added.
rate=8.000000e01, log=1.753933e-321
Reaction: asp-TT(0)WWAA => asp + TT(0)WWAA added.
rate=2.500000e07, log=1.753933e-321
Reaction: asp-TT(0)WWAAp => asp + TT(0)WWAAp added.
rate=6.000000e-07, log=1.753933e-321
Reaction: TT(1)WWAA + asp => asp-TT(1)WWAA added.
rate=9.000000e03, log=1.753933e-321
Reaction: TT(1)WWAAp + asp => asp-TT(1)WWAAp added.
rate=5.000000e-02, log=1.753933e-321

The log10() function always gives the same, incorrect answer regardless of
the input.  Can anyone help with this?



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