Files
crankshaft/release/python/0.7.0/crankshaft/crankshaft/analysis_data_provider.py
Rafa de la Torre a1198627b5 Release 0.7.0
2018-02-23 15:45:12 +01:00

99 lines
3.3 KiB
Python

"""class for fetching data"""
import plpy
import pysal_utils as pu
NULL_VALUE_ERROR = ('No usable data passed to analysis. Check your input rows '
'for null values and fill in appropriately.')
def verify_data(func):
"""decorator to verify data result before returning to algorithm"""
def wrapper(*args, **kwargs):
"""Error checking"""
try:
data = func(*args, **kwargs)
if not data:
plpy.error(NULL_VALUE_ERROR)
else:
return data
except Exception as err:
plpy.error('Analysis failed: {}'.format(err))
return []
return wrapper
class AnalysisDataProvider(object):
@verify_data
def get_getis(self, w_type, params):
"""fetch data for getis ord's g"""
query = pu.construct_neighbor_query(w_type, params)
return plpy.execute(query)
@verify_data
def get_markov(self, w_type, params):
"""fetch data for spatial markov"""
query = pu.construct_neighbor_query(w_type, params)
return plpy.execute(query)
@verify_data
def get_moran(self, w_type, params):
"""fetch data for moran's i analyses"""
query = pu.construct_neighbor_query(w_type, params)
return plpy.execute(query)
@verify_data
def get_nonspatial_kmeans(self, params):
"""
Fetch data for non-spatial k-means.
Inputs - a dict (params) with the following keys:
colnames: a (text) list of column names (e.g.,
`['andy', 'cookie']`)
id_col: the name of the id column (e.g., `'cartodb_id'`)
subquery: the subquery for exposing the data (e.g.,
SELECT * FROM favorite_things)
Output:
A SQL query for packaging the data for consumption within
`KMeans().nonspatial`. Format will be a list of length one,
with the first element a dict with keys ('rowid', 'attr1',
'attr2', ...)
"""
agg_cols = ', '.join([
'array_agg({0}) As arr_col{1}'.format(val, idx+1)
for idx, val in enumerate(params['colnames'])
])
query = '''
SELECT {cols}, array_agg({id_col}) As rowid
FROM ({subquery}) As a
'''.format(subquery=params['subquery'],
id_col=params['id_col'],
cols=agg_cols).strip()
return plpy.execute(query)
@verify_data
def get_spatial_kmeans(self, params):
"""fetch data for spatial kmeans"""
query = '''
SELECT
array_agg("{id_col}" ORDER BY "{id_col}") as ids,
array_agg(ST_X("{geom_col}") ORDER BY "{id_col}") As xs,
array_agg(ST_Y("{geom_col}") ORDER BY "{id_col}") As ys
FROM ({subquery}) As a
WHERE "{geom_col}" IS NOT NULL
'''.format(**params)
return plpy.execute(query)
@verify_data
def get_gwr(self, params):
"""fetch data for gwr analysis"""
query = pu.gwr_query(params)
return plpy.execute(query)
@verify_data
def get_gwr_predict(self, params):
"""fetch data for gwr predict"""
query = pu.gwr_predict_query(params)
return plpy.execute(query)