def import_propensities_from_flows(self, flows_df, inplace=False):
"""
Calculate a set of import propensities from `flows_df`
The input DataFrame must be indexed with ['sector', 'from_country',
'to_country']. Any ['sector', 'to_country'] combinations which sum to
less than 1 have the remainder assigned to RoW
"""
sum_y = flows_df.groupby(level=['to_country', 'sector']).sum()
some_ip = dataframe.broadcast(flows_df, sum_y, binary_operator='div')
# Re-include any sectors dropped due to divide by zero or not included
# in flows_df at all:
all_ip = some_ip.reindex(self._import_propensities.index)
all_ip[all_ip.isnull()] = self._import_propensities
# Set from RoW propensity to 1 anywhere the total over to_country and
# sector is zero
# TODO: This doesn't work yet!
#sums = all_ip.groupby(level=['sector', 'to_country']).sum()
#fixed_ip = all_ip.unstack('from_country')
#fixed_ip['RoW'] = 1 - sums
#fixed_ip.loc[pd.IndexSlice[:, 'RoW'], 'RoW'] = 0 # Set RoW/RoW to zero
#fixed_ip = fixed_ip.stack()
#fixed_ip = fixed_ip.reorder_levels(['sector', 'from_country', 'to_country']).sortlevel()
if inplace:
self._import_propensities = all_ip
return all_ip
def _split_flows_by_import_propensities(self, flows,
country_field='country',
country_names=None,
with_RoW=False):
"""
Calculate country to country flows using
the given flows vector and the import propensities
"""
ip = self._import_propensities.astype(float)
return dataframe.broadcast(self._import_propensities, flows)
def _import_propensities_from_flows(flows_df):
"""
Calculate y_ijs / sum_i(y_ijs) for every flow in flows_df
"""
sum_y = flows_df.groupby(level=["to_country", "sector"]).sum()
ip = dataframe.broadcast(flows_df, sum_y, binary_operator="div")
# Re-include any sectors dropped due to divide by zero:
ip = ip.reindex(flows_df.index).fillna(0)
# Set from RoW propensity to 1 anywhere the total over to_country and sector is zero
sums = ip.groupby(level=["to_country", "sector"]).sum()
zero_sums = sums[sums == 0]
ip.loc[[("RoW",) + idx for idx in zero_sums.index.values]] = 1
return ip.reorder_levels(["sector", "from_country", "to_country"]).sortlevel()
