mesh parsing example

notebooks/2015-05-29-parsing-mesh-files.ipynb

@@ -0,0 +1,191 @@
+{
+ "cells": [
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "Let's collect here examples how to parse mesh files (i.e. topologies; nodes and connectivity) from different kind of sources."
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 1,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [],
+   "source": [
+    "f = open(\"../testdata/tripod.GiD.msh\");\n",
+    "data = readlines(f)\n",
+    "close(f)"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 2,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "data": {
+      "text/plain": [
+       "Dict{Any,Any} with 0 entries"
+      ]
+     },
+     "execution_count": 2,
+     "metadata": {},
+     "output_type": "execute_result"
+    }
+   ],
+   "source": [
+    "type Node\n",
+    "    node_id\n",
+    "    coords\n",
+    "end\n",
+    "type Element\n",
+    "    element_id\n",
+    "    node_ids\n",
+    "end\n",
+    "nodes = Dict()\n",
+    "elements = Dict()"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 3,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "Entering section Coordinates\n",
+      "Leaving section Coordinates\n",
+      "Entering section Elements\n",
+      "Leaving section Elements\n",
+      "Mesh parsed\n"
+     ]
+    }
+   ],
+   "source": [
+    "section = \"\"\n",
+    "for line in data\n",
+    "    line = strip(line)\n",
+    "    if line == \"Coordinates\" || line == \"Elements\"\n",
+    "        section = line\n",
+    "        println(\"Entering section \",section)\n",
+    "    end\n",
+    "    if beginswith(line, \"end\")\n",
+    "        println(\"Leaving section \",section)\n",
+    "        section = \"\"\n",
+    "    end\n",
+    "    if section == \"Coordinates\"\n",
+    "        m = matchall(r\"[-0-9.]+\", line)\n",
+    "        if length(m) == 0\n",
+    "            continue\n",
+    "        end\n",
+    "        id = integer(m[1])\n",
+    "        coords = float(m[2:end])\n",
+    "        nodes[id] = Node(id, coords)\n",
+    "    end\n",
+    "    if section == \"Elements\"\n",
+    "        #println(line)\n",
+    "        m = matchall(r\"[0-9]+\", line)\n",
+    "        #println(m)\n",
+    "        if length(m) == 0\n",
+    "            continue\n",
+    "        end\n",
+    "        id = integer(m[1])\n",
+    "        #println(line)\n",
+    "        #println(m)\n",
+    "        #print(id)\n",
+    "        node_ids = m[2:end]\n",
+    "        #println(id,node_ids)\n",
+    "        elements[id] = Element(id, map(integer, node_ids))\n",
+    "    end\n",
+    "end\n",
+    "println(\"Mesh parsed\")"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 4,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "data": {
+      "text/plain": [
+       "10-element Array{Int64,1}:\n",
+       " 1411\n",
+       " 1527\n",
+       " 1338\n",
+       " 1581\n",
+       " 1467\n",
+       " 1431\n",
+       " 1375\n",
+       " 1494\n",
+       " 1557\n",
+       " 1455"
+      ]
+     },
+     "execution_count": 4,
+     "metadata": {},
+     "output_type": "execute_result"
+    }
+   ],
+   "source": [
+    "elements[100].node_ids"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 5,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "data": {
+      "text/plain": [
+       "10-element Array{Node,1}:\n",
+       " Node(1411,[1.55541,4.93615,12.9066])\n",
+       " Node(1527,[3.55077,4.78495,12.5057])\n",
+       " Node(1338,[1.26995,2.70013,12.9378])\n",
+       " Node(1581,[2.09046,5.60655,10.2598])\n",
+       " Node(1467,[2.56484,4.86055,12.7445])\n",
+       " Node(1431,[2.42483,3.74254,12.7719])\n",
+       " Node(1375,[1.41281,3.81814,12.923]) \n",
+       " Node(1494,[1.82293,5.27135,11.5832])\n",
+       " Node(1557,[2.82062,5.19575,11.3827])\n",
+       " Node(1455,[1.68021,4.15334,11.5988])"
+      ]
+     },
+     "execution_count": 5,
+     "metadata": {},
+     "output_type": "execute_result"
+    }
+   ],
+   "source": [
+    "map(id -> nodes[id], elements[100].node_ids)"
+   ]
+  }
+ ],
+ "metadata": {
+  "kernelspec": {
+   "display_name": "Julia 0.3.8",
+   "language": "julia",
+   "name": "julia-0.3"
+  },
+  "language_info": {
+   "name": "julia",
+   "version": "0.3.8"
+  }
+ },
+ "nbformat": 4,
+ "nbformat_minor": 0
+}