Exporting time history data from multiple nodes

[Flaxman]

I am modeling the vibration over a floor slab and want to export the displacement time history for a large number of nodes into a text or excel file (so that I can then manipulate the data to find the maximum velocity at each point).

Is there a way of getting the time history for a range of nodes, rather than selecting them one by one?

Thanks in advance

 

[Drej]

Try the following as a starter for ten (save the following to a text file - you will need to be in /post26 before you read this file in):

! ======= OUTPUT TIME HISTORY DATA TO ASCII FILE ========
cmsel,s,EQP_DISPS ! select a component for output

*get,num_n,NODE,0,COUNT ! get number of nodes
*get,n_min,NODE,0,NUM,MIN ! get min node number

*do,i,1,num_n,1 ! output to ascii by looping over nodes
curr_n=n_min
nsol,10,curr_n,u,x ! output UX
nsol,20,curr_n,u,y ! output UY
nsol,30,curr_n,u,z ! output UZ

*dim,N%curr_n%_output,array,10000,4

vget,N%curr_n%_output(1,1),1 ! put time in array
vget,N%curr_n%_output(1,2),10 ! put UX in array
vget,N%curr_n%_output(1,3),20 ! put UY in array
vget,N%curr_n%_output(1,4),30 ! put UZ in array

*cfopen,N%curr_n%,dat
*vwrite,N%curr_n%_output(1,1),N%curr_n%_output(1,2),N%curr_n%_output(1,3),N%curr_n%_output(1,4)
(4(E15.6))
*cfopen

*get,n_min,NODE,curr_n,NXTH
*enddo

! ========================


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[maxibonne]

Drej

I am trying to modify your file in order to get the maximum temperature reached by each node at the end of the analysis. Currently my code looks like this and I have a query about the 1st line: what is EQP_DISPS?


cmsel,s,EQP_DISPS ! select a component for output

*get,num_n,NODE,0,COUNT ! get number of nodes
*get,n_min,NODE,0,NUM,MIN ! get min node number

*do,i,1,num_n,1 ! output to ascii by looping over nodes
curr_n=n_min
nsol,10,curr_n,temp ! output temp


*dim,N%curr_n%_output,array,100,2

vget,N%curr_n%_output(1,1),1 ! put time in array
vget,N%curr_n%_output(1,2),10 ! put temp in array

*cfopen,N%curr_n%,dat
*vwrite,N%curr_n%_output(1,1),N%curr_n%_output(1,2)
(4(E15.6))
*cfopen

*get,n_min,NODE,curr_n,NXTH
*enddo

 

[Drej]

EQP_DISPS is the name of a node component that was generated earlier in the analysis e.g:

nsel,s,node,,1,10 ! select nodes 1 to 10
cm,EQP_DISPS,node ! save these nodes in a component
alls

then the code as before:

cmsel,s,EQP_DISPS ! select a component for output

*get,num_n,NODE,0,COUNT ! get number of nodes
*get,n_min,NODE,0,NUM,MIN ! get min node number

etc.
etc.
etc.


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[maxibonne]

thanks.

another question if you don't mind please: what is "(4(E15.6))" towards the end?

thank you for your time; I am finding your answers very useful in my work

 

[balu25]

thats in what format the results to be written, check help for *vwrite..

 

[Flaxman]

Thanks for the tips.

A message keeps popping up for each iteration of the loop saying
"Redimensioning parameter NXXX_OUTPUT will erase all current values. SHOULD THE *DIM COMMAND BE EXECUTED?"

How can I prevent this message from appearing (I guess that somehow I have to delete the parameter before defining its dimensions?)

 

[balu25]

u can try, i am not so sure if it is possible to delete it.

 

[Flaxman]

I managed to get around the problem by changing the name of the output files to MXXX_OUTPUT, IXXX_OUTPUT etc for each analysis

This did the trick for a while, but now I get an error message saying that there are too many defined parameters, and I have exceeded the limit of 5000.

I have tried working in a different directory but this doesnt solve the problem. The software must be making a record somewhere of each parameter that is defined. I just need to find a way of un-defining or deleting the old parameters. This would also solve the problem of constantly having to find new names for the parameters.
Any ideas?