Subject: Re: CCL:SHAKE in Charmm

From: Tru Huynh <[email-masked]>
Date: Thu, 28 Jun 2001 11:56:10 +0200

"Xiang(Simon) Wang" wrote:
> 
> Dear CCLers:
> 
> I met the following ERROR message when running SHAKE BONH within a TIP3
> droplet model:
> 
> CHARMM> SHAKE BONH
> SHKSET: *** ERROR *** NO. OF CONSTRAINTS 45091 IS LARGER THAN MAXSHK 45090
> *** LEVEL -2 WARNING *** BOMLEV IS -2
> 
> My version of Charmm is c25b2, compiled w/ large and FULL.
> 
You just need to recompile a bigger CHARMM version.

1)make a XLARGE version
or
2)modify line 26 of source/fcm/dimens.fcm
> from
      PARAMETER (LARGE=60120, MEDIUM=25140, SMALL=6120)
to
      PARAMETER (LARGE=100000, MEDIUM=25140, SMALL=6120)

----- extract of dimens.fcm ----
CHARMM Element source/fcm/dimens.fcm 1.1
C
C This common file contains all useful dimensioning information.
C                                   BRB - 01/12/89
C
C-----------------------------------------------------------------------
C     Standard Size parameters
C
C   XLARGE version - ~240,000 atoms 
C   LARGE  version -  ~60,000 atoms
C   MEDIUM version -  ~25,000 atoms
C   SMALL  version -   ~6,000 atoms
C   XSMALL version -   ~2,000 atoms
C   REDUCE version - A special version for non-virtual memory machines.
C                    There is an attempt to greatly limit static memory.
C
C   The actual size varies by machine type.
C   It is listed in the header of the CHARMM output file.
C
      INTEGER LARGE,MEDIUM,SMALL,REDUCE
##IF QUANTA
      PARAMETER (LARGE=60000, MEDIUM=30000, SMALL=15000)
##ELIF T3D
      PARAMETER (LARGE=30120, MEDIUM=20160, SMALL=6120)
##ELSE
      PARAMETER (LARGE=60120, MEDIUM=25140, SMALL=6120) 
##ENDIF
      PARAMETER (REDUCE=15000)
      INTEGER SIZE
##IF XLARGE
      PARAMETER (SIZE=LARGE*4)
##ELIF LARGE
      PARAMETER (SIZE=LARGE)
##ELIF MEDIUM
      PARAMETER (SIZE=MEDIUM)
##ELIF REDUCE
      PARAMETER (SIZE=REDUCE)
##ELIF SMALL
      PARAMETER (SIZE=SMALL)
##ELIF XSMALL
      PARAMETER (SIZE=SMALL/3)
##ENDIF

<...>
C-----------------------------------------------------------------------
C  FROM:  shake.fcm
C
C  MAXSHK - The maximum number of SHAKE constraints.
C
      INTEGER MAXSHK
##IF XSMALL
      PARAMETER (MAXSHK = 20)
##ELIF REDUCE
      PARAMETER (MAXSHK = 5120)
##ELSE
      PARAMETER (MAXSHK = SIZE*3/4)
##ENDIF
C

-- 
Dr Tru Huynh          | Bioinformatique Structurale
mailto:[email-masked] | tel/fax +33 1 45 68 87 37/19
Institut Pasteur, 25-28 rue du Docteur Roux, 75724 Paris CEDEX 15 France