********> bugfix.45
Correction Author: David A. Pearlman
Correction Date: 7/31/92  

Programs: GIBBS

Severity: slight

Problem: 

       If the default value for NDMPMC is used (frequency of "dumping"
       to the MICSTAT file), and the simulation results in more than
       100 windows being collected, the numbers of equilibration and
       data collection steps reported for the first window, the
       101st window, the 201st window, etc. in the MICSTAT file
       will be incorrect. (The average numbers of equilibration/data
       collection steps reported at the end of the file will similarly
       be wrong).

       The simulation is correct. The correct numbers of equilibration
       and data collection steps will have been collected. All free energy
       values reported are correct. The only error is in the values 
       reported for these step counters in MICSTAT.

Affects: 

        The reported numbers of equilibration and data collection steps
        every 1+N*100 windows will be in error in MICSTAT. This is only a
        reporting error. No part of the calculation, or any of the results,
        is in error.

Cause: 

        A comparison statment was incorrectly allowing values to be
        stored in the "101st" location in an array dimension for only
        100 elements.

Fix:  Make the following change to routine MICST in file micst.f

*** OLD micst.f
--- NEW micst.f
***************
*** 182,189 ****
        IEQUIL = 0
        ICOLL = 1
  C
!       IF (NCOUNT.GT.MXBUF.OR.(NCOUNT.GT.NDUMP.AND.NDUMP.GT.0))
!      *GO TO 1201
        RETURN
  C
--- 182,189 ----
        IEQUIL = 0
        ICOLL = 1
  C
!       IF (NCOUNT.GE.MXBUF.OR.(NCOUNT.GT.NDUMP.AND.NDUMP.GT.0))
       *GO TO 1201
        RETURN
  C
------------------------------------------------------------------------------
(.GT. becomes .GE.)

Temporary workarounds: 

     Setting NDMPMC to 99 (or any value >0 and <100) will avoid the problem.
     In most cases, the error will be of negligable significance. The user
     should simply be aware of its origin.

Routines affected:

     GIBBS   Routine MICST in file ...amber4/src/micst.f

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