Re: [ESPResSo-devel] Bond-deleting strangeness

[Florian Weik]

Hi,

the function looks suspicious to me, might be an off by one error. I'll get back to you if I've got it figured out.

Florian

On Wed, Jan 7, 2015 at 3:45 PM, Rudolf Weeber <address@hidden> wrote:

Hi,
On Wed, Jan 07, 2015 at 02:42:27PM +0100, Rudolf Weeber wrote:
> I encountered very strange behaviour when deleting individual bonds from particles which have more than one bond.
> In some cases, the code works correctly, in some cases, the wrong bond seems to be deleted and in some cases, the bond list gets screwed up completely.
> The code, which is supposed to delete the bond is in particle_data.cpp:try_delete_bond()
And here is a case, where the bond list is screwed up entirely:


{0 FENE 47.396 2.5 1.0} {1 angle_harmonic 473.96000000000004 1.0471975512} {2 FENE 473960.0 2.0 1.0} {3 FENE 473960.0 0.1 0.0} {1 1 lennard-jones 1000.0 2.672696154421018 3.0 0.25 0.0 0.0 0.0 } {magnetic 1.0  dawaanr }
I.e., bond 0 and 2 have one partner, bond 1 has two partners



Initial bond configurations
{ {0 21746} {0 21747} {0 22047} {1 22047 21746} {1 22049 21747} {1 22348 22047} {1 22349 22049} }
  Del: 0 21746
{ {0 21747} {0 22047} {1 22047 21746} {1 22049 21747} {22047 1} {22047 1} {22349 22049} }
                                                      ---------------------------------

The relevant code is
proc makeBondRigid { id bond} {
global bondMeshPairSoft 0
global bondMeshAngleSoft 1
global bondMeshPairStiff 2
global bondParticleMesh 3

 puts "$id: Making bond rigid: $bond"
 # First delete the old bond
 puts "[part $id print bond]"
 puts "  Del: $bond"
 eval "part $id bond delete $bond"
 puts "[part $id print bond]"

 # Make new bond with changed type
 lset bond 0 $bondMeshPairStiff
 # Add
 puts "  Add: $bond"
 eval "part $id bond $bond"
 puts "[part $id print bond]"
}


Regards, Rudolf

--

Florian Weik

address@hidden
++49 157 85939252