Fix #38

Author: virgesmith

setup.py

@@ -12,7 +12,7 @@ def read_reqs():
 
 setuptools.setup(
   name='ukpopulation',
-  version="1.2.0",
+  version="1.2.1",
   description='Download, cache, collate, filter, manipulate and extrapolate UK population and household estimates/projections',
   long_description=readme(),
   long_description_content_type="text/markdown",

ukpopulation/customsnppdata.py

@@ -43,16 +43,18 @@ def __init__(self, name, cache_dir=utils.default_cache_dir()):
     filename = _custom_snpp_filename(name, self.cache_dir)
     self.data = pd.read_csv(filename)
 
-  def min_year(self):
+  def min_year(self, _=None):
     """
     Returns the first year in the projection
+    (usused argument to make interface consistent with SNPPData)
     """
     # convert to country if necessary
     return min(self.data.PROJECTED_YEAR_NAME.unique())
 
-  def max_year(self):
+  def max_year(self, _=None):
     """
     Returns the final year in the projection
+    (usused argument to make interface consistent with SNPPData)
     """
     return max(self.data.PROJECTED_YEAR_NAME.unique())
 
@@ -153,7 +155,7 @@ def create_variant(self, variant_name, npp, geog_codes, year_range):
       # split out any years prior to the NPP data (currently SNPP is 2014 based but NPP is 2016)
       (pre_range, in_range) = utils.split_range(year_range, npp.min_year() - 1)
       # for any years prior to NPP we just use the SNPP data as-is (i.e. "ppp")
-      pre_data = self.filter(geog_code, pre_range)
+      pre_data = self.filter(geog_code, pre_range) if pre_range else pd.DataFrame()
       if len(pre_data) > 0:
         print("WARNING: variant {} not applied for years {} that predate the NPP data".format(variant_name, pre_range))
 

ukpopulation/nppdata.py

@@ -99,7 +99,7 @@ def detail(self, variant_name, geog, years=None, ages=range(0,91), genders=[1,2]
       genders = [genders]
 
     if not variant_name in NPPData.VARIANTS:
-      raise RuntimeError("invalid variant name: " + variant_name)
+      raise RuntimeError("invalid NPP variant name: " + variant_name)
     # make years a valid range (this *silently* removes invalid years)
     years = utils.trim_range(years, self.min_year(), self.max_year())