From 9141e2a00fbaf7afb7a87bfa4c74903d7414e560 Mon Sep 17 00:00:00 2001
From: Adam Nelson <nelsonag@umich.edu>
Date: Tue, 17 Nov 2015 20:30:16 -0500
Subject: [PATCH] Updated testing harness and input_set for MG tests and added
 first MG test: test_mg_basic

---
 tests/c5g7_mgxs.xml                  | 383 +++++++++++++++++++++++++++
 tests/input_set.py                   | 162 +++++++++++
 tests/test_mg_basic/inputs_true.dat  |   1 +
 tests/test_mg_basic/results_true.dat |   2 +
 tests/test_mg_basic/test_mg_basic.py |  17 ++
 tests/testing_harness.py             |   9 +-
 6 files changed, 571 insertions(+), 3 deletions(-)
 create mode 100644 tests/c5g7_mgxs.xml
 create mode 100644 tests/test_mg_basic/inputs_true.dat
 create mode 100644 tests/test_mg_basic/results_true.dat
 create mode 100644 tests/test_mg_basic/test_mg_basic.py

diff --git a/tests/c5g7_mgxs.xml b/tests/c5g7_mgxs.xml
new file mode 100644
index 0000000000..ec85d4b593
--- /dev/null
+++ b/tests/c5g7_mgxs.xml
@@ -0,0 +1,383 @@
+<?xml version="1.0"?>
+<library>
+  <!-- Before getting to the data, set common information -->
+  <groups> 7 </groups>
+  <group_structure>
+    1E-11 0.0635E-6 10.0E-6 1.0E-4 1.0E-3 0.5 1.0 20.0
+  </group_structure>
+
+  <!--
+    Move on to the data.  Each <xsdata> has a unique id and label.
+  -->
+  <xsdata>
+    <!-- Meta data for this data -->
+    <name>UO2.71c</name>
+    <alias>UO2.71c</alias>
+    <kT> 2.53E-8 </kT> <!-- in MeV -->
+    <order>0</order>
+    <fissionable>true</fissionable>
+    <!-- Optional (default is isotropic) -->
+    <representation>isotropic</representation>
+
+    <!-- The data itself, like tallies,
+      goes from low energies (groups) to high energies
+    -->
+    <absorption>
+      8.0248E-03 3.7174E-03 2.6769E-02 9.6236E-02 3.0020E-02 1.1126E-01 2.8278E-01
+    </absorption>
+
+    <nu_fission>
+      2.005998E-02 2.027303E-03 1.570599E-02 4.518301E-02 4.334208E-02 2.020901E-01 5.257105E-01
+    </nu_fission>
+
+    <chi>
+      5.8791E-01 4.1176E-01 3.3906E-04 1.1761E-07 0.0000E+00 0.0000E+00 0.0000E+00
+    </chi>
+    <fission>
+      7.21206E-03 8.19301E-04 6.45320E-03 1.85648E-02 1.78084E-02 8.30348E-02 2.16004E-01
+    </fission>
+
+    <!-- units of MeV/cm -->
+    <!-- If no kappa fission tallies, this is not needed; it will not be loaded
+         if there is no kappa fission scores anyways -->
+    <k_fission>
+      1.0 1.0 1.0 1.0 1.0 1.0 1.0
+    </k_fission>
+
+    <!-- for consistency must include nu-scatter -->
+    <!-- will be a matrix of (order+1) x g_in x g_out -->
+    <scatter>
+      0.1275370 0.0423780 0.0000094 0.0000000 0.0000000 0.0000000 0.0000000
+      0.0000000 0.3244560 0.0016314 0.0000000 0.0000000 0.0000000 0.0000000
+      0.0000000 0.0000000 0.4509400 0.0026792 0.0000000 0.0000000 0.0000000
+      0.0000000 0.0000000 0.0000000 0.4525650 0.0055664 0.0000000 0.0000000
+      0.0000000 0.0000000 0.0000000 0.0001253 0.2714010 0.0102550 0.0000000
+      0.0000000 0.0000000 0.0000000 0.0000000 0.0012968 0.2658020 0.0168090
+      0.0000000 0.0000000 0.0000000 0.0000000 0.0000000 0.0085458 0.2730800
+    </scatter>
+
+    <!-- If total is not provided, it will be calculated.
+    However, in the C5G7 problems, we want to use a transport-corrected value
+    so we dont want to have it be calculated -->
+    <total>
+      0.1779492 0.3298048 0.4803882 0.5543674000000001  0.3118013 0.39516779999999996 0.5644058
+    </total>
+
+  </xsdata>
+
+  <xsdata>
+    <!-- Meta data for this data -->
+    <name>MOX1.71c</name>
+    <alias>MOX1.71c</alias>
+    <kT> 2.53E-8 </kT> <!-- in MeV -->
+    <order>0</order>
+    <fissionable>true</fissionable>
+
+    <!-- The data itself, like tallies,
+      goes from low energies (groups) to high energies
+    -->
+    <absorption>
+      8.4339E-03 3.7577E-03 2.7970E-02 1.0421E-01 1.3994E-01 4.0918E-01 4.0935E-01
+    </absorption>
+    <!--
+      Since chi_vector is false, this will be a matrix
+      Matrix is g_in, g_out.
+      This is to show that you can either use a chi vector + nu_fission vector,
+      like in the UO2 data, or a nu_fission matrix like here.
+    -->
+    <nu_fission>
+      1.27888062E-02  8.95701528E-03  7.37557218E-06  2.55837033E-09  0.00000000E+00  0.00000000E+00  0.00000000E+00
+      1.49041240E-03  1.04385401E-03  8.59552023E-07  2.98153464E-10  0.00000000E+00  0.00000000E+00  0.00000000E+00
+      9.56411400E-03  6.69850756E-03  5.51582469E-06  1.91327830E-09  0.00000000E+00  0.00000000E+00  0.00000000E+00
+      3.84928781E-02  2.69596154E-02  2.21996483E-05  7.70040890E-09  0.00000000E+00  0.00000000E+00  0.00000000E+00
+      1.80629998E-02  1.26509513E-02  1.04173100E-05  3.61346022E-09  0.00000000E+00  0.00000000E+00  0.00000000E+00
+      3.91930789E-01  2.74500216E-01  2.26034688E-04  7.84048241E-08  0.00000000E+00  0.00000000E+00  0.00000000E+00
+      4.19762096E-01  2.93992687E-01  2.42085585E-04  8.39724109E-08  0.00000000E+00  0.00000000E+00  0.00000000E+00
+    </nu_fission>
+
+    <fission>
+      7.62704E-03 8.76898E-04 5.69835E-03 2.28872E-02 1.07635E-02 2.32757E-01 2.48968E-01
+    </fission>
+
+     <!-- units of MeV/cm -->
+    <k_fission>
+      1.0 1.0 1.0 1.0 1.0 1.0 1.0
+    </k_fission>
+
+    <!-- for consistency must include nu-scatter -->
+    <!-- will be a matrix of (order+1) x g_in x g_out -->
+    <scatter>
+      1.27537000E-01  4.23780000E-02  9.43740000E-06  5.51630000E-09  0.00000000E+00  0.00000000E+00  0.00000000E+00
+      0.00000000E+00  3.24456000E-01  1.63140000E-03  3.14270000E-09  0.00000000E+00  0.00000000E+00  0.00000000E+00
+      0.00000000E+00  0.00000000E+00  4.50940000E-01  2.67920000E-03  0.00000000E+00  0.00000000E+00  0.00000000E+00
+      0.00000000E+00  0.00000000E+00  0.00000000E+00  4.52565000E-01  5.56640000E-03  0.00000000E+00  0.00000000E+00
+      0.00000000E+00  0.00000000E+00  0.00000000E+00  1.25250000E-04  2.71401000E-01  1.02550000E-02  1.00210000E-08
+      0.00000000E+00  0.00000000E+00  0.00000000E+00  0.00000000E+00  1.29680000E-03  2.65802000E-01  1.68090000E-02
+      0.00000000E+00  0.00000000E+00  0.00000000E+00  0.00000000E+00  0.00000000E+00  8.54580000E-03  2.73080000E-01
+    </scatter>
+
+    <total>
+      0.1783583429163 0.3298451031427 0.4815892 0.5623414 0.421721260021 0.6930878 0.6909757999999999
+    </total>
+
+  </xsdata>
+
+  <xsdata>
+    <!-- Meta data for this data -->
+    <name>MOX2.71c</name>
+    <alias>MOX2.71c</alias>
+    <kT> 2.53E-8 </kT> <!-- in MeV -->
+    <order>0</order>
+    <fissionable>true</fissionable>
+
+    <!-- The data itself, like tallies,
+      goes from low energies (groups) to high energies
+    -->
+    <absorption>
+      0.0090657 0.0042967 0.032881 0.12203 0.18298 0.56846 0.58521
+    </absorption>
+    <!--
+      Since chi_vector is false, this will be a matrix
+      Matrix is g_in, g_out !!! Need to get these values looking right to match
+      output of a nu-fission tally with <energy> filter above <energyout> filter
+    -->
+    <nu_fission>
+      1.40004593E-02  9.80563205E-03  8.07435789E-06  2.80075866E-09  0.00000000E+00  0.00000000E+00  0.00000000E+00
+      2.26856185E-03  1.58885378E-03  1.30832709E-06  4.53820413E-10  0.00000000E+00  0.00000000E+00  0.00000000E+00
+      1.41886199E-02  9.93741584E-03  8.18287404E-06  2.83839974E-09  0.00000000E+00  0.00000000E+00  0.00000000E+00
+      5.54788444E-02  3.88562347E-02  3.19958106E-05  1.10984111E-08  0.00000000E+00  0.00000000E+00  0.00000000E+00
+      2.69085702E-02  1.88462058E-02  1.55187355E-05  5.38299559E-09  0.00000000E+00  0.00000000E+00  0.00000000E+00
+      5.45687127E-01  3.82187973E-01  3.14709185E-04  1.09163414E-07  0.00000000E+00  0.00000000E+00  0.00000000E+00
+      6.13307712E-01  4.29548032E-01  3.53707392E-04  1.22690752E-07  0.00000000E+00  0.00000000E+00  0.00000000E+00
+    </nu_fission>
+
+    <fission>
+      0.00825446 0.00132565 0.00842156 0.032873 0.0159636 0.323794 0.362803
+    </fission>
+
+     <!-- units of MeV/cm -->
+    <k_fission>
+      1.0 1.0 1.0 1.0 1.0 1.0 1.0
+    </k_fission>
+
+    <!-- for consistency must include nu-scatter -->
+    <!-- will be a matrix of (order+1) x g_in x g_out -->
+    <scatter>
+      1.30457000E-01  4.17920000E-02  8.51050000E-06  5.13290000E-09  0.00000000E+00  0.00000000E+00  0.00000000E+00
+      0.00000000E+00  3.28428000E-01  1.64360000E-03  2.20170000E-09  0.00000000E+00  0.00000000E+00  0.00000000E+00
+      0.00000000E+00  0.00000000E+00  4.58371000E-01  2.53310000E-03  0.00000000E+00  0.00000000E+00  0.00000000E+00
+      0.00000000E+00  0.00000000E+00  0.00000000E+00  4.63709000E-01  5.47660000E-03  0.00000000E+00  0.00000000E+00
+      0.00000000E+00  0.00000000E+00  0.00000000E+00  1.76190000E-04  2.82313000E-01  8.72890000E-03  9.00160000E-09
+      0.00000000E+00  0.00000000E+00  0.00000000E+00  0.00000000E+00  2.27600000E-03  2.49751000E-01  1.31140000E-02
+      0.00000000E+00  0.00000000E+00  0.00000000E+00  0.00000000E+00  0.00000000E+00  8.86450000E-03  2.59529000E-01
+    </scatter>
+
+    <total>
+      0.1813232156329 0.3343683022017 0.4937851 0.5912156 0.47419809900160004 0.833601 0.8536035
+    </total>
+
+  </xsdata>
+
+  <xsdata>
+    <!-- Meta data for this data -->
+    <name>MOX3.71c</name>
+    <alias>MOX3.71c</alias>
+    <kT> 2.53E-8 </kT> <!-- in MeV -->
+    <order>0</order>
+    <fissionable>true</fissionable>
+
+    <!-- The data itself, like tallies,
+      goes from low energies (groups) to high energies
+    -->
+    <absorption>
+      9.48620000E-03 4.65560000E-03 3.62400000E-02 1.32720000E-01 2.08400000E-01 6.58700000E-01 6.90170000E-01
+    </absorption>
+    <!--
+      Since chi_vector is false, this will be a matrix
+      Matrix is g_in, g_out !!! Need to get these values looking right to match
+      output of a nu-fission tally with <energy> filter above <energyout> filter
+    -->
+    <nu_fission>
+      1.48071013E-02  1.03705874E-02  8.53956516E-06  2.96212546E-09  0.00000000E+00  0.00000000E+00  0.00000000E+00
+      2.78640474E-03  1.95154023E-03  1.60697792E-06  5.57413653E-10  0.00000000E+00  0.00000000E+00  0.00000000E+00
+      1.73304404E-02  1.21378819E-02  9.99482763E-06  3.46691346E-09  0.00000000E+00  0.00000000E+00  0.00000000E+00
+      6.59928975E-02  4.62200600E-02  3.80594850E-05  1.32017225E-08  0.00000000E+00  0.00000000E+00  0.00000000E+00
+      3.25131926E-02  2.27715674E-02  1.87510386E-05  6.50418701E-09  0.00000000E+00  0.00000000E+00  0.00000000E+00
+      6.32002662E-01  4.42641588E-01  3.64489161E-04  1.26430632E-07  0.00000000E+00  0.00000000E+00  0.00000000E+00
+      7.28595687E-01  5.10293344E-01  4.20196380E-04  1.45753838E-07  0.00000000E+00  0.00000000E+00  0.00000000E+00
+    </nu_fission>
+
+    <fission>
+      8.67209000E-03 1.62426000E-03 1.02716000E-02 3.90447000E-02 1.92576000E-02 3.74888000E-01 4.30599000E-01
+    </fission>
+
+     <!-- units of MeV/cm -->
+    <k_fission>
+      1.0 1.0 1.0 1.0 1.0 1.0 1.0
+    </k_fission>
+
+    <!-- for consistency must include nu-scatter -->
+    <!-- will be a matrix of (order+1) x g_in x g_out -->
+    <scatter>
+      1.31504000E-01  4.20460000E-02  8.69720000E-06  5.19380000E-09  0.00000000E+00  0.00000000E+00  0.00000000E+00
+      0.00000000E+00  3.30403000E-01  1.64630000E-03  2.60060000E-09  0.00000000E+00  0.00000000E+00  0.00000000E+00
+      0.00000000E+00  0.00000000E+00  4.61792000E-01  2.47490000E-03  0.00000000E+00  0.00000000E+00  0.00000000E+00
+      0.00000000E+00  0.00000000E+00  0.00000000E+00  4.68021000E-01  5.43300000E-03  0.00000000E+00  0.00000000E+00
+      0.00000000E+00  0.00000000E+00  0.00000000E+00  1.85970000E-04  2.85771000E-01  8.39730000E-03  8.92800000E-09
+      0.00000000E+00  0.00000000E+00  0.00000000E+00  0.00000000E+00  2.39160000E-03  2.47614000E-01  1.23220000E-02
+      0.00000000E+00  0.00000000E+00  0.00000000E+00  0.00000000E+00  0.00000000E+00  8.96810000E-03  2.56093000E-01
+    </scatter>
+
+    <total>
+      1.83044902E-01 3.36704903E-01 5.00506900E-01 6.06174000E-01 5.02754279E-01 9.21027600E-01 9.55231100E-01
+    </total>
+
+  </xsdata>
+
+  <xsdata>
+    <!-- Meta data for this data -->
+    <name>FC.71c</name>
+    <alias>FC.71c</alias>
+    <kT> 2.53E-8 </kT> <!-- in MeV -->
+    <order>0</order>
+    <fissionable>true</fissionable>
+
+    <!-- The data itself, like tallies,
+      goes from low energies (groups) to high energies
+    -->
+    <absorption>
+      5.1132E-04 7.5813E-05 3.1643E-04 1.1675E-03 3.3977E-03 9.1886E-03 2.3244E-02
+    </absorption>
+
+    <nu_fission>
+      1.323401E-08 1.434500E-08 1.128599E-06 1.276299E-05 3.538502E-07 1.740099E-06 5.063302E-06
+    </nu_fission>
+
+    <chi>
+      5.8791E-01 4.1176E-01 3.3906E-04 1.1761E-07 0.0000E+00 0.0000E+00 0.0000E+00
+    </chi>
+
+    <fission>
+      4.79002E-09 5.82564E-09 4.63719E-07 5.24406E-06 1.45390E-07 7.14972E-07 2.08041E-06
+    </fission>
+
+     <!-- units of MeV/cm -->
+    <k_fission>
+      1.0 1.0 1.0 1.0 1.0 1.0 1.0
+    </k_fission>
+
+    <!-- for consistency must include nu-scatter -->
+    <!-- will be a matrix of (order+1) x g_in x g_out -->
+    <scatter>
+      6.61659000E-02  5.90700000E-02  2.83340000E-04  1.46220000E-06  2.06420000E-08  0.00000000E00 0.00000000E00
+      0.00000000E00 2.40377000E-01  5.24350000E-02  2.49900000E-04  1.92390000E-05  2.98750000E-06  4.21400000E-07
+      0.00000000E00 0.00000000E00 1.83425000E-01  9.22880000E-02  6.93650000E-03  1.07900000E-03  2.05430000E-04
+      0.00000000E00 0.00000000E00 0.00000000E00 7.90769000E-02  1.69990000E-01  2.58600000E-02  4.92560000E-03
+      0.00000000E00 0.00000000E00 0.00000000E00 3.73400000E-05  9.97570000E-02  2.06790000E-01  2.44780000E-02
+      0.00000000E00 0.00000000E00 0.00000000E00 0.00000000E00 9.17420000E-04  3.16774000E-01  2.38760000E-01
+      0.00000000E00 0.00000000E00 0.00000000E00 0.00000000E00 0.00000000E00 4.97930000E-02  1.09910000E00
+    </scatter>
+
+    <total>
+      1.26032048E-01 2.93160367E-01 2.84250824E-01 2.81025244E-01 3.34460185E-01 5.65640735E-01 1.17213908E00
+    </total>
+
+  </xsdata>
+
+  <xsdata>
+    <!-- Meta data for this data -->
+    <name>GT.71c</name>
+    <alias>GT.71c</alias>
+    <kT> 2.53E-8 </kT> <!-- in MeV -->
+    <order>0</order>
+    <fissionable>false</fissionable>
+
+    <!-- The data itself, like tallies,
+      goes from low energies (groups) to high energies
+    -->
+    <absorption>
+      5.11320000E-04 7.58010000E-05 3.15720000E-04 1.15820000E-03 3.39750000E-03 9.18780000E-03 2.32420000E-02
+    </absorption>
+
+    <!-- for consistency must include nu-scatter -->
+    <!-- will be a matrix of (order+1) x g_in x g_out -->
+    <scatter>
+      6.61659000E-02  5.90700000E-02  2.83340000E-04  1.46220000E-06  2.06420000E-08  0.00000000E+00  0.00000000E+00
+      0.00000000E+00  2.40377000E-01  5.24350000E-02  2.49900000E-04  1.92390000E-05  2.98750000E-06  4.21400000E-07
+      0.00000000E+00  0.00000000E+00  1.83297000E-01  9.23970000E-02  6.94460000E-03  1.08030000E-03  2.05670000E-04
+      0.00000000E+00  0.00000000E+00  0.00000000E+00  7.88511000E-02  1.70140000E-01  2.58810000E-02  4.92970000E-03
+      0.00000000E+00  0.00000000E+00  0.00000000E+00  3.73330000E-05  9.97372000E-02  2.06790000E-01  2.44780000E-02
+      0.00000000E+00  0.00000000E+00  0.00000000E+00  0.00000000E+00  9.17260000E-04  3.16765000E-01  2.38770000E-01
+      0.00000000E+00  0.00000000E+00  0.00000000E+00  0.00000000E+00  0.00000000E+00  4.97920000E-02  1.09912000E+00
+    </scatter>
+
+    <total>
+      1.26032043E-01 2.93160349E-01 2.84240290E-01 2.80960000E-01 3.34440033E-01 5.65640060E-01 1.17215400E+00
+    </total>
+  </xsdata>
+
+  <xsdata>
+    <!-- Meta data for this data -->
+    <name>LWTR.71c</name>
+    <alias>LWTR.71c</alias>
+    <kT> 2.53E-8 </kT> <!-- in MeV -->
+    <order>0</order>
+    <fissionable>false</fissionable>
+
+    <!-- The data itself, like tallies,
+      goes from low energies (groups) to high energies
+    -->
+    <absorption>
+      6.0105E-04 1.5793E-05 3.3716E-04 1.9406E-03 5.7416E-03 1.5001E-02 3.7239E-02
+    </absorption>
+
+    <!-- for consistency must include nu-scatter -->
+    <!-- will be a matrix of (order+1) x g_in x g_out -->
+    <scatter>
+      0.0444777 0.1134000 0.0007235 0.0000037 0.0000001 0.0000000 0.0000000
+      0.0000000 0.2823340 0.1299400 0.0006234 0.0000480 0.0000074 0.0000010
+      0.0000000 0.0000000 0.3452560 0.2245700 0.0169990 0.0026443 0.0005034
+      0.0000000 0.0000000 0.0000000 0.0910284 0.4155100 0.0637320 0.0121390
+      0.0000000 0.0000000 0.0000000 0.0000714 0.1391380 0.5118200 0.0612290
+      0.0000000 0.0000000 0.0000000 0.0000000 0.0022157 0.6999130 0.5373200
+      0.0000000 0.0000000 0.0000000 0.0000000 0.0000000 0.1324400 2.4807000
+    </scatter>
+
+    <total>
+      0.15920605  0.41296959299999997 0.59030986  0.5843499999999999  0.7180000000000001  1.2544497000000001  2.650379
+    </total>
+
+  </xsdata>
+
+  <xsdata>
+    <!-- Meta data for this data -->
+    <name>CR.71c</name>
+    <alias>CR.71c</alias>
+    <kT> 2.53E-8 </kT> <!-- in MeV -->
+    <order>0</order>
+    <fissionable>false</fissionable>
+
+    <!-- The data itself, like tallies,
+      goes from low energies (groups) to high energies
+    -->
+    <absorption>
+      1.70490000E-03 8.36224000E-03 8.37901000E-02 3.97797000E-01 6.98763000E-01 9.29508000E-01 1.17836000E+00
+    </absorption>
+
+    <!-- for consistency must include nu-scatter -->
+    <!-- will be a matrix of (order+1) x g_in x g_out -->
+    <scatter>
+      1.70563000E-01  4.44012000E-02  9.83670000E-05  1.27786000E-07  0.00000000E+00  0.00000000E+00  0.00000000E+00
+      0.00000000E+00  4.71050000E-01  6.85480000E-04  3.91395000E-10  0.00000000E+00  0.00000000E+00  0.00000000E+00
+      0.00000000E+00  0.00000000E+00  8.01859000E-01  7.20132000E-04  0.00000000E+00  0.00000000E+00  0.00000000E+00
+      0.00000000E+00  0.00000000E+00  0.00000000E+00  5.70752000E-01  1.46015000E-03  0.00000000E+00  0.00000000E+00
+      0.00000000E+00  0.00000000E+00  0.00000000E+00  6.55562000E-05  2.07838000E-01  3.81486000E-03  3.69760000E-09
+      0.00000000E+00  0.00000000E+00  0.00000000E+00  0.00000000E+00  1.02427000E-03  2.02465000E-01  4.75290000E-03
+      0.00000000E+00  0.00000000E+00  0.00000000E+00  0.00000000E+00  0.00000000E+00  3.53043000E-03  6.58597000E-01
+    </scatter>
+
+    <total>
+      2.16767595E-01 4.80097720E-01 8.86369232E-01 9.70009150E-01 9.10481420E-01 1.13775017E+00 1.84048743E+00
+    </total>
+  </xsdata>
+</library>
diff --git a/tests/input_set.py b/tests/input_set.py
index 87b857f4a9..4e8974680e 100644
--- a/tests/input_set.py
+++ b/tests/input_set.py
@@ -569,3 +569,165 @@ class InputSet(object):
         plot.color = 'mat'
 
         self.plots.add_plot(plot)
+
+class MGInputSet(InputSet):
+    def build_default_materials_and_geometry(self):
+        # Define materials needed for C5G7 2-D UO2 Assembly
+        uo2_data = openmc.Macroscopic('UO2', '71c')
+        uo2 = openmc.Material(name='UO2', material_id=1)
+        uo2.set_density('macro', 1.0)
+        uo2.add_macroscopic(uo2_data)
+
+        fiss_cham_data = openmc.Macroscopic('FC', '71c')
+        fiss_cham = openmc.Material(name='FC', material_id=2)
+        fiss_cham.set_density('macro', 1.0)
+        fiss_cham.add_macroscopic(fiss_cham_data)
+
+        guide_tube_data = openmc.Macroscopic('GT', '71c')
+        guide_tube = openmc.Material(name='GT', material_id=3)
+        guide_tube.set_density('macro', 1.0)
+        guide_tube.add_macroscopic(guide_tube_data)
+
+        water_data = openmc.Macroscopic('LWTR', '71c')
+        water = openmc.Material(name='LWTR', material_id=4)
+        water.set_density('macro', 1.0)
+        water.add_macroscopic(water_data)
+
+        # Define the materials file.
+        self.materials.default_xs = '71c'
+        self.materials.add_materials((uo2, fiss_cham, guide_tube, water))
+
+        # Define surfaces.
+
+        # Pin cell
+        s1 = openmc.ZCylinder(R=0.54, surface_id=1)
+        # Assembly/Problem Boundary
+        left   = openmc.XPlane(x0=0.0, surface_id=20,
+                               boundary_type='reflective')
+        right  = openmc.XPlane(x0=21.42, surface_id=21,
+                               boundary_type='reflective')
+        bottom = openmc.YPlane(y0=0.0, surface_id=22,
+                               boundary_type='reflective')
+        top    = openmc.YPlane(y0=21.42, surface_id=23,
+                               boundary_type='reflective')
+        down   = openmc.ZPlane(z0=0.0, surface_id=24,
+                               boundary_type='reflective')
+        up     = openmc.ZPlane(z0=21.42, surface_id=25,
+                               boundary_type='reflective')
+
+        # Define pin cells
+        # uo2 pin
+        c10 = openmc.Cell(cell_id=10)
+        c10.region = -s1
+        c10.fill = uo2
+        c11 = openmc.Cell(cell_id=11)
+        c11.region = +s1
+        c11.fill = water
+        fuel_pin = openmc.Universe(name='Fuel pin', universe_id=1)
+        fuel_pin.add_cells((c10, c11))
+
+        # Fission chamber pin
+        c20 = openmc.Cell(cell_id=20)
+        c20.region = -s1
+        c20.fill = fiss_cham
+        c21 = openmc.Cell(cell_id=21)
+        c21.region = +s1
+        c21.fill = water
+        fiss_chamber_pin = openmc.Universe(name='Fission Chamber', universe_id=2)
+        fiss_chamber_pin.add_cells((c20, c21))
+
+        # Guide Tube pin
+        c30 = openmc.Cell(cell_id=30)
+        c30.region = -s1
+        c30.fill = guide_tube
+        c31 = openmc.Cell(cell_id=31)
+        c31.region = +s1
+        c31.fill = water
+        gt_pin = openmc.Universe(name='Guide Tube', universe_id=3)
+        gt_pin.add_cells((c30, c31))
+
+        # Define fuel lattice
+        l100 = openmc.RectLattice(name='UO2 assembly', lattice_id=100)
+        l100.dimension = (17, 17)
+        l100.lower_left = (-10.71, -10.71)
+        l100.pitch = (1.26, 1.26)
+        l100.universes = [
+             [fuel_pin]*17,
+             [fuel_pin]*17,
+             [fuel_pin]*5 + [gt_pin] + [fuel_pin]*2 + [gt_pin]
+                + [fuel_pin]*2 + [gt_pin] + [fuel_pin]*5,
+             [fuel_pin]*3 + [gt_pin] + [fuel_pin]*9 + [gt_pin]
+                + [fuel_pin]*3,
+             [fuel_pin]*17,
+             [fuel_pin]*2 + [gt_pin] + [fuel_pin]*2 + [gt_pin]
+                + [fuel_pin]*2 + [gt_pin] + [fuel_pin]*2 + [gt_pin]
+                + [fuel_pin]*2 + [gt_pin] + [fuel_pin]*2,
+             [fuel_pin]*17,
+             [fuel_pin]*17,
+             [fuel_pin]*2 + [gt_pin] + [fuel_pin]*2 + [gt_pin]
+                + [fuel_pin]*2 + [fiss_chamber_pin] + [fuel_pin]*2 + [gt_pin]
+                + [fuel_pin]*2 + [gt_pin] + [fuel_pin]*2,
+             [fuel_pin]*17,
+             [fuel_pin]*17,
+             [fuel_pin]*2 + [gt_pin] + [fuel_pin]*2 + [gt_pin]
+                + [fuel_pin]*2 + [gt_pin] + [fuel_pin]*2 + [gt_pin]
+                + [fuel_pin]*2 + [gt_pin] + [fuel_pin]*2,
+             [fuel_pin]*17,
+             [fuel_pin]*3 + [gt_pin] + [fuel_pin]*9 + [gt_pin]
+                + [fuel_pin]*3,
+             [fuel_pin]*5 + [gt_pin] + [fuel_pin]*2 + [gt_pin]
+                + [fuel_pin]*2 + [gt_pin] + [fuel_pin]*5,
+             [fuel_pin]*17,
+             [fuel_pin]*17 ]
+
+        # Define assemblies.
+        fa = openmc.Universe(name='Fuel assembly', universe_id=10)
+        c100 = openmc.Cell(cell_id=110)
+        c100.region = +down & -up
+        c100.fill = l100
+        fa.add_cells((c100, ))
+
+        # Define core lattices
+        l200 = openmc.RectLattice(name='Core lattice', lattice_id=200)
+        l200.dimension = (1, 1)
+        l200.lower_left = (0.0, 0.0)
+        l200.pitch = (21.42, 21.42)
+        l200.universes = [[fa]]
+
+        # Define root universe.
+        root = openmc.Universe(universe_id=0, name='root universe')
+        c1 = openmc.Cell(cell_id=1)
+        c1.region = +left & -right & +bottom & -top & +down & -up
+        c1.fill = l200
+
+        root.add_cells((c1,))
+
+        # Define the geometry file.
+        geometry = openmc.Geometry()
+        geometry.root_universe = root
+
+        self.geometry.geometry = geometry
+
+
+    def build_default_settings(self):
+        self.settings.batches = 10
+        self.settings.inactive = 5
+        self.settings.particles = 100
+        self.settings.set_source_space('box', (0.0, 0.0, 0.0, 21.42, 21.42, 100.0))
+        self.settings.energy_mode = "multi-group"
+        self.settings.cross_sections = "../c5g7_mgxs.xml"
+
+    def build_defualt_plots(self):
+        plot = openmc.Plot()
+        plot.filename = 'mat'
+        plot.origin = (10.71, 10.71, 50.0)
+        plot.width = (21.42, 21.42)
+        plot.pixels = (3000, 3000)
+        plot.color = 'mat'
+
+        self.plots.add_plot(plot)
+
+
+
+
+
diff --git a/tests/test_mg_basic/inputs_true.dat b/tests/test_mg_basic/inputs_true.dat
new file mode 100644
index 0000000000..d576cd402a
--- /dev/null
+++ b/tests/test_mg_basic/inputs_true.dat
@@ -0,0 +1 @@
+b41c9621e2f068dab8f44b4fbf29aa5f075c04e463543550b7d1324b75b4709db810808e64474d2400c8c36465814bcca095650b0e19d640860dd4a860bb40a3
\ No newline at end of file
diff --git a/tests/test_mg_basic/results_true.dat b/tests/test_mg_basic/results_true.dat
new file mode 100644
index 0000000000..93683d28bb
--- /dev/null
+++ b/tests/test_mg_basic/results_true.dat
@@ -0,0 +1,2 @@
+k-combined:
+1.359283E+00 7.465863E-02
diff --git a/tests/test_mg_basic/test_mg_basic.py b/tests/test_mg_basic/test_mg_basic.py
new file mode 100644
index 0000000000..1a49ee8a82
--- /dev/null
+++ b/tests/test_mg_basic/test_mg_basic.py
@@ -0,0 +1,17 @@
+#!/usr/bin/env python
+
+import os
+import sys
+sys.path.insert(0, os.pardir)
+from testing_harness import TestHarness, PyAPITestHarness
+import openmc
+
+
+class MGBasicTestHarness(PyAPITestHarness):
+    def _build_inputs(self):
+        super(MGBasicTestHarness, self)._build_inputs()
+
+
+if __name__ == '__main__':
+    harness = MGBasicTestHarness('statepoint.10.*', False, mg=True)
+    harness.main()
diff --git a/tests/testing_harness.py b/tests/testing_harness.py
index ed89f76946..90f35078a6 100644
--- a/tests/testing_harness.py
+++ b/tests/testing_harness.py
@@ -12,7 +12,7 @@ import sys
 import numpy as np
 
 sys.path.insert(0, os.path.join(os.pardir, os.pardir))
-from input_set import InputSet
+from input_set import InputSet, MGInputSet
 from openmc.statepoint import StatePoint
 from openmc.executor import Executor
 import openmc.particle_restart as pr
@@ -273,9 +273,12 @@ class ParticleRestartTestHarness(TestHarness):
 
 
 class PyAPITestHarness(TestHarness):
-    def __init__(self, statepoint_name, tallies_present=False):
+    def __init__(self, statepoint_name, tallies_present=False, mg=False):
         TestHarness.__init__(self, statepoint_name, tallies_present)
-        self._input_set = InputSet()
+        if mg:
+            self._input_set = MGInputSet()
+        else:
+            self._input_set = InputSet()
 
     def execute_test(self):
         """Build input XMLs, run OpenMC, and verify correct results."""