Files
crankshaft/release/python/0.5.1/crankshaft/crankshaft/analysis_data_provider.py
T

68 lines
2.2 KiB
Python

"""class for fetching data"""
import plpy
import pysal_utils as pu
class AnalysisDataProvider:
def get_getis(self, w_type, params):
"""fetch data for getis ord's g"""
try:
query = pu.construct_neighbor_query(w_type, params)
result = plpy.execute(query)
# if there are no neighbors, exit
if len(result) == 0:
return pu.empty_zipped_array(4)
else:
return result
except plpy.SPIError, err:
plpy.error('Analysis failed: %s' % err)
def get_markov(self, w_type, params):
"""fetch data for spatial markov"""
try:
query = pu.construct_neighbor_query(w_type, params)
data = plpy.execute(query)
if len(data) == 0:
return pu.empty_zipped_array(4)
return data
except plpy.SPIError, err:
plpy.error('Analysis failed: %s' % err)
def get_moran(self, w_type, params):
"""fetch data for moran's i analyses"""
try:
query = pu.construct_neighbor_query(w_type, params)
data = plpy.execute(query)
# if there are no neighbors, exit
if len(data) == 0:
return pu.empty_zipped_array(2)
return data
except plpy.SPIError, err:
plpy.error('Analysis failed: %s' % e)
return pu.empty_zipped_array(2)
def get_nonspatial_kmeans(self, query):
"""fetch data for non-spatial kmeans"""
try:
data = plpy.execute(query)
return data
except plpy.SPIError, err:
plpy.error('Analysis failed: %s' % err)
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)
try:
data = plpy.execute(query)
return data
except plpy.SPIError, err:
plpy.error('Analysis failed: %s' % err)