fix(sfr): remove sensitivity to SFR reach_data (ds2) rec array order. (…

…#637)

* making sfr reachdata (ds2) write insensitive to data field order

currently uses dtype.descr which can fail is struct array fields change
order.

* happend upon etvr not evtr in evt package

* Adding test that exposes issue with passing disordered reach_data arrays

* tidy-up

autotest/t009_test.py

@@ -398,7 +398,6 @@ def test_ds_6d_6e_disordered():
     sfr = m.get_package("SFR")
     sfr2 = m2.get_package("SFR")
 
-
     if len(sfr.graph) != len(sfr2.graph):
         raise AssertionError
 
@@ -416,6 +415,28 @@ def test_ds_6d_6e_disordered():
                 raise AssertionError
 
 
+def test_disordered_reachdata_fields():
+    path = os.path.join("..", "examples", "data", "hydmod_test")
+    wpath = os.path.join(".", "temp", "t009_disorderfields")
+    m = flopy.modflow.Modflow.load("test1tr2.nam",
+                                   model_ws=path)
+    sfr = m.get_package("SFR")
+    orig_reach_data = sfr.reach_data
+    # build shuffled rec array
+    shuffled_fields = list(set(orig_reach_data.dtype.names))
+    data = []
+    names = []
+    formats = []
+    for field in shuffled_fields:
+        data.append(orig_reach_data[field])
+        names.append(field)
+        formats.append(orig_reach_data.dtype[field].str)
+    reach_data = np.rec.fromarrays(data, names=names, formats=formats)
+    m.sfr.reach_data = reach_data
+    m.change_model_ws(wpath)
+    m.write_input()
+
+
 def test_transient_example():
     path = os.path.join('temp', 't009')
     gpth = os.path.join('..', 'examples', 'data', 'mf2005_test', 'testsfr2.*')
@@ -488,14 +509,16 @@ def test_sfr_plot():
     #assert True
     pass
 
+
 if __name__ == '__main__':
     # test_sfr()
     # test_ds_6d_6e_disordered()
+    test_disordered_reachdata_fields()
     # test_sfr_renumbering()
     # test_example()
     # test_export()
-    #test_transient_example()
-    #test_sfr_plot()
+    # test_transient_example()
+    # mtest_sfr_plot()
     # test_assign_layers()
     # test_SfrFile()
     # test_const()

flopy/modflow/mfsfr2.py

@@ -1605,7 +1605,7 @@ def _write_reach_data(self, f_sfr):
         for idx in ['k', 'i', 'j', 'node']:
             if (idx in columns):
                 d[idx] += 1
-        d = d[columns]
+        d = d[columns]  # data columns sorted
         formats = _fmt_string(d)[:-1] + '\n'
         for rec in d:
             f_sfr.write(formats.format(*rec))
@@ -2805,8 +2805,8 @@ def _get_item2_names(nstrm, reachinput, isfropt, structured=False):
 
 def _fmt_string(array, float_format='{!s}'):
     fmt_string = ''
-    for field in array.dtype.descr:
-        vtype = field[1][1].lower()
+    for field in array.dtype.names:  # data already sorted
+        vtype = array.dtype[field].str[1].lower()
         if vtype == 'v':
             continue
         if vtype == 'i':