# Contents of /trunk/doc/examples/cookbook/example01a.py

Revision 3892 - (show annotations)
Tue Apr 10 08:57:23 2012 UTC (6 years, 9 months ago) by jfenwick
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```Merged changes across from the attempt2 branch.
This version builds and passes python2 tests.
It also passes most python3 tests.

```
 1 2 from __future__ import print_function 3 ######################################################## 4 # 5 # Copyright (c) 2009 by University of Queensland 6 # Earth Systems Science Computational Center (ESSCC) 7 8 # 9 # Primary Business: Queensland, Australia 10 # Licensed under the Open Software License version 3.0 11 12 # 13 ######################################################## 14 15 __copyright__="""Copyright (c) 2009 by University of Queensland 16 Earth Systems Science Computational Center (ESSCC) 17 http://www.uq.edu.au/esscc 18 Primary Business: Queensland, Australia""" 19 __license__="""Licensed under the Open Software License version 3.0 20 21 __url__= 22 23 """ 24 Author: Antony Hallam antony.hallam@uqconnect.edu.au 25 """ 26 ############################################################FILE HEADER 27 # example01a.py 28 # Model temperature diffusion between two granite blocks of unequal 29 # initial temperature. Solve for total energy in the system. 30 31 #######################################################EXTERNAL MODULES 32 # To solve the problem it is necessary to import the modules we require. 33 from esys.escript import * # This imports everything from the escript library 34 from esys.escript.unitsSI import * 35 from esys.escript.linearPDEs import LinearPDE # This defines LinearPDE as LinearPDE 36 from esys.finley import Rectangle # This imports the rectangle domain function 37 38 #################################################ESTABLISHING VARIABLES 39 #Domain related. 40 mx = 500*m #meters - model length 41 my = 100*m #meters - model width 42 ndx = 100 # mesh steps in x direction 43 ndy = 1 # mesh steps in y direction - one dimension means one element 44 boundloc = mx/2 # location of boundary between the two blocks 45 #PDE related 46 rho = 2750. *kg/m**3 #kg/m{3} density of iron 47 cp = 790.*J/(kg*K) # J/Kg.K thermal capacity 48 rhocp = rho*cp 49 kappa = 2.2*W/m/K # watts/m.Kthermal conductivity 50 qH=0 * J/(sec*m**3) # J/(sec.m{3}) no heat source 51 T1=20 * Celsius # initial temperature at Block 1 52 T2=2273. * Celsius # base temperature at Block 2 53 54 55 ################################################ESTABLISHING PARAMETERS 56 t=0 * day # our start time, usually zero 57 tend=50 * yr # - time to end simulation 58 outputs = 200 # number of time steps required. 59 h=(tend-t)/outputs #size of time step 60 #user warning statement 61 print("Expected Number of time outputs is: ", (tend-t)/h) 62 i=0 #loop counter 63 #the folder to put our outputs in, leave blank "" for script path 64 save_path= os.path.join("data","example01") 65 #ensure the dir exists 66 mkDir(save_path, os.path.join(save_path,"tempT")) 67 68 ####################################################DOMAIN CONSTRUCTION 69 blocks = Rectangle(l0=mx,l1=my,n0=ndx, n1=ndy) 70 71 ###############################################ESCRIPT PDE CONSTRUCTION 72 #... open PDE and set coefficients ... 73 mypde=LinearPDE(blocks) 74 mypde.setSymmetryOn() 75 A=zeros((2,2)) 76 A[0,0]=kappa 77 mypde.setValue(A=A,D=rhocp/h) 78 # ... set initial temperature .... 79 x=Solution(blocks).getX() 80 T= T1*whereNegative(x[0]-boundloc)+T2*(1-whereNegative(x[0]-boundloc)) 81 82 ########################################################START ITERATION 83 while t