compute reduce does not work in parallel

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1

Hi,

I am executing the following line in order to find out which atom has the highest enegy

compute 2 body pe/atom
compute 3 all property/atom id
compute 4 all reduce max c_3 c_2 replace 2 1

thermo_style custom step c_4[1]
run 0

when I use one processor it immediately runs and gives the answer. On the other hand when I use multiple processors it just gets stuck and does not run. I was wondering if there is a bug in compute_reduce

Thanks,
Sina

2

Hi,

I am executing the following line in order to find out which atom has the
highest enegy

compute 2 body pe/atom
compute 3 all property/atom id
compute 4 all reduce max c_3 c_2 replace 2 1

thermo_style custom step c_4[1]
run 0

when I use one processor it immediately runs and gives the answer. On the
other hand when I use multiple processors it just gets stuck and does not
run. I was wondering if there is a bug in compute_reduce

hmmm... your compute 2 is over the group "body"
but 3 and 4 are over the group "all".

that doesn't look right to me.

axel.

3

My apologies, originally it was all the groups was “body” I changed it to “all” when I transferred it to the mailing list, I forgot to change compute 2. No that is not the problem

compute 2 all pe/atom
compute 3 all property/atom id
compute 4 all reduce max c_3 c_2 replace 2 1

thermo_style custom step c_4[1]
run 0

4

My apologies, originally it was all the groups was "body" I changed it to
"all" when I transferred it to the mailing list, I forgot to change compute
2. No that is not the problem

compute 2 all pe/atom

compute 3 all property/atom id

please change this line:

compute 4 all reduce max c_3 c_2 replace 2 1

into this

compute 4 all reduce max c_3 c_2 replace 1 2

which is consistent with the documentation,
    axel

5

Thanks that solved my problem.