# UNV2X base code, J.Cugnoni, www.caelinux.com,9.2006
# Licence: GPL
# Purpose: this is a set of objects & functions to read a Universal File
# into a simple FEM object structure in order to simplify the
# conversion of Mesh definitions from UNV to any other format
# How it works:
# This code is based on two main objects:
# 1) a simple FEM object structure to store nodes, elements and groups
# 2) a UNVParser which provides a simple & modular solution to read
# some datasets from UNV file and store them in a FEM object structure
# To Do: add UNV data handler functions for other datasets (to be defined)
# add your own code to write the model into your own file format
import os
import os.path
import sys
class FEM:
""" a simple FEM object structure"""
def __init__(self):
self.nnodes=0
self.nelems=0
self.nnodesets=0
self.nelemsets=0
self.nodes=[]
self.elems=[]
self.nodesets=[]
self.elemsets=[]
class Node:
""" a single node object """
def __init__(self,id,coords):
self.id=id
self.coords=coords
class Element:
""" a single finite element object"""
def __init__(self,id,type,material,color,nnodes,cntvt):
self.id=id
self.type=type
self.material=material
self.color=color
self.nnodes=nnodes
self.cntvt=cntvt
class Group:
""" FE group object """
def __init__(self,id,name):
self.id=id
self.type=0
self.name=name
self.nitems=0
self.items=[]
def Line2Float(line):
"""Convert a string into a list of Float"""
return map(float,line.split())
def Line2Int(line):
"""Convert a string into a list of Int"""
return map(int,line.split())
def UNV2411Reader(file,FEM):
""" reads an UNV2411 dataset (nodes) from file and store data in FEM structure
return an updated FEM object"""
endFlag=' -1'
loop=True
while loop:
line1=file.readline()
line2=file.readline()
if len(line2)>0:
if line1.startswith(endFlag):
loop=False
break
else:
dataline=Line2Int(line1)
coords=Line2Float(line2)
FEM.nodes.append(Node(dataline[0],coords))
FEM.nnodes=FEM.nnodes+1
else:
loop=False
return FEM
def UNV2412Reader(file,FEM):
""" reads an UNV2412 dataset (elements) from file and store data in FEM structure
return an updated FEM object"""
endFlag=' -1'
SpecialElemTypes=[11] # types of elements which are defined on 3 lines
loop=True
while loop:
line1=file.readline()
line2=file.readline()
if len(line2)>0:
if line1.startswith(endFlag):
loop=False
break
else:
dataline=Line2Int(line1)
eltype=dataline[1]
nnodes=dataline[-1]
if eltype<33:
# 1D elements have an additionnal line in their definition
line3=file.readline()
cntvt=Line2Int(line3)
else:
# standard elements have their connectivities on secnd line
cntvt=Line2Int(line2)
if nnodes>8:
cntvt.extend(Line2Int(file.readline()))
if nnodes>16:
cntvt.extend(Line2Int(file.readline()))
if nnodes>24:
cntvt.extend(Line2Int(file.readline()))
FEM.elems.append(Element(dataline[0],dataline[1],0,0,dataline[5],cntvt))
FEM.nelems=FEM.nelems+1
else:
loop=False
return FEM
def UNV2467Reader(file,FEM):
""" reads an UNV2467 dataset (groups) from file and store data in FEM structure
return an updated FEM object"""
endFlag=' -1'
loop=True
while loop:
line1=file.readline()
line2=file.readline()
if len(line2)>0:
if line1.startswith(endFlag):
loop=False
break
else:
# read group
dataline=Line2Int(line1)
groupname=line2
id=dataline[0]
nitems=dataline[7]
nlines=(nitems+1)/2
# read group items
lst=[]
for i in range(nlines):
dat=Line2Int(file.readline())
lst.append(dat[0:3])
if len(dat)>4:
lst.append(dat[4:7])
# split group in node & element sets
nset=Group(id,groupname)
elset=Group(id,groupname)
nset.type=7
elset.type=8
for item in lst:
if item[0]==7:
nset.items.append(item[1])
if item[0]==8:
elset.items.append(item[1])
nset.nitems=len(nset.items)
elset.nitems=len(elset.items)
# store non empty groups
if nset.nitems>0:
FEM.nodesets.append(nset)
if elset.nitems>0:
FEM.elemsets.append(elset)
FEM.nnodesets=len(FEM.nodesets)
FEM.nelemsets=len(FEM.elemsets)
else:
loop=False
return FEM
class UNVParser:
""" Universal file parser class"""
def __init__(self,filename):
self.file=None
self.filename=filename
self.FEM=FEM()
self.startFlag=' -1'
self.endFlag=' -1'
# list of supported datasets and corresponding dataset handler functions
self.datasetsIds=[2411,2412,2467]
self.datasetsHandlers=[UNV2411Reader,UNV2412Reader,UNV2467Reader]
self.sections=[]
def scanfile(self):
""" Read file & fill the section list"""
loop=True
while loop:
line=self.file.readline()
if len(line)>0:
if line.startswith(self.startFlag):
# identify section & save offset
id=int(self.file.readline())
offset=self.file.tell()
self.sections.append([id,offset])
# ignore data until end of section
while not(self.file.readline().startswith(self.endFlag)):
pass
else:
loop=False
# rewind file
self.file.seek(0)
def parse(self):
""" parse UNV file to fill the FEM data structure"""
self.file=open(self.filename,'r')
self.scanfile()
for sectionId,offset in self.sections:
if (sectionId in self.datasetsIds):
self.file.seek(offset)
func=self.datasetsHandlers[self.datasetsIds.index(sectionId)]
self.FEM=func(self.file,self.FEM)
self.file.close()
return self.FEM
if __name__=='__main__':
helpmsg=""" UNV2X: example of use, write data in separate text files
usage: UNV2X unvfile prefix
what it does: read unvfile, create an internal FEM object structure
in memory and writes the following files:
prefix.nodes, prefix.elems, prefix.groups
"""
if len(sys.argv)==3:
unvfile=sys.argv[1]
prefix=sys.argv[2]
# read UNV file in FEM object structure
UNV=UNVParser(unvfile)
FEM=UNV.parse()
# write files
ls=os.linesep
# node file
nf=open(prefix + '.nodes','w')
for node in FEM.nodes:
nf.write(('%5d, %8g, %8g, %8g'+ls) % (node.id,node.coords[0],node.coords[1],node.coords[2]))
nf.close()
# element file
ef=open(prefix + '.elems','w')
for elem in FEM.elems:
dat=[elem.id,elem.type,elem.material,elem.color,elem.nnodes]
dat.extend([x for x in elem.cntvt])
format='%5d, ' * (4 + elem.nnodes) + ' %5d' + ls
ef.write(format % tuple(dat))
ef.close()
# group file
grouptypes={7:'NodeSet',8:'ElementSet'}
gf=open(prefix + '.groups','w')
for group in (FEM.nodesets + FEM.elemsets):
gf.write(('%s(%d) Id: %d'+ls) % (grouptypes[group.type],group.type,group.id))
gf.write('Name: %s' % (group.name))
count=0
lst=group.items
for i in range(group.nitems):
count=count+1
if (count<8)&(i<>group.nitems-1):
gf.write('%5d, ' % lst.pop(0))
else:
gf.write(('%5d'+ls) % lst.pop(0))
count=0
gf.close()
else:
print(helpmsg)