def fetch(x_beg, x_end, y_beg, y_end, time_bin):
global Point_RDD
global coordinate_cache
global DEFAULT_CACHE_SIZE
filtered = filter(lambda pr: x_end > pr[0] > x_beg and y_end > pr[1] > y_beg, coordinate_cache)
visible_area = area(x_beg, x_end, y_beg, y_end)
s_area = sample_area(filtered)
if s_area < visible_area/20:
print "zooming out"
print len(filtered)
if len(filtered) < SAMPLE_SIZE or s_area <= visible_area/20:
filtered_RDD = Point_RDD.filter(lambda pr: x_end > pr[0] > x_beg and y_end > pr[1] > y_beg)
coordinate_cache = filtered_RDD.takeSample(False, DEFAULT_CACHE_SIZE)
if len(coordinate_cache) < DEFAULT_CACHE_SIZE:
flag_limit_reached = True
filtered = filter(lambda pr: x_end > pr[0] > x_beg and y_end > pr[1] > y_beg, coordinate_cache)
print len(filtered)
return Sampling.sample_unzip(filtered, SAMPLE_SIZE)
def get_current():
sample_array = Sampling.sample_unzip(coordinate_cache, SAMPLE_SIZE)
return sample_array
