def linear_time_interpolate(self, t0, t1, xlat, xlon, xalt, time):
"""Interpolates between files
t0, t1, and time are assumed to be datetime objects"""
if self.interpolators.has_key((t0, t1)):
model0, model1 = self.interpolators[(t0, t1)]
else: # need to get interpolator if it's available
file0 = self.get_file_for_time(t0)
if file0 is None:
print 'no file for time', t0
for filename, interval in self.file_times.items():
if time_in_interval(time, interval):
print 'found time in interval'
for k, v in self.file_times.items():
print k, v, v[0] <= t0 <= v[1]
raise IOError("no file for {}".format(t0))
file1 = self.get_file_for_time(t1)
try:
model0 = self.interpolators[self.file_times[file0]]
model1 = self.interpolators[self.file_times[file1]]
except:
print file0, file1
raise
self.interpolators[(t0, t1)] = model0, model1
d0 = model0.density(xlat, xlon, xalt,
model0.ut[-1]) #end time of last file
d1 = model1.density(xlat, xlon, xalt,
model1.ut[0]) # first time in next file
w = (time - t0) / (t1 - t0)
return d0 * (1.0 - w) + d1 * w
def density(self, xlat, xlon, xalt, gregorian_string, raise_errors = False, debug = False):
self.interpolations +=1
if self.interpolations%1000 == 0:
print xlat, xlon, xalt, gregorian_string, self.interpolations
try:
time = pd.to_datetime(gregorian_string)
if not time_in_interval(time, self.last_interval):
filename = self.get_file_for_time(time) # look for time in file date ranges
if filename is not None: # found time in file
self.last_interval = self.file_times[filename] # so we can jump straight to interpolation next time
else: # file not in time ranges
closest_files = self.time_in_range(time) # see if time is in data gap between files
if closest_files is not None: # linearly interpolate between these two
t0 = self.file_times[closest_files[0]][1]
t1 = self.file_times[closest_files[1]][0]
return self.linear_time_interpolate(t0, t1, xlat, xlon, xalt, time)
else: # outside all available data
raise ValueError('Could not find time in files')
model = self.interpolators[self.last_interval]
try:
density = model.density(xlat, xlon, xalt, model.time_to_ut(time))
except:
# import ipdb; ipdb.set_trace()
raise
return density
except:
if raise_errors:
print 'TIEGCM error at xlat: {}, xlon: {}, xalt: {}, gregorian str: {}'.format(xlat, xlon, xalt, gregorian_string)
print 'last interval:', self.last_interval
raise
else:
return 0
def get_file_for_time(self, time):
for filename, interval in self.file_times.items():
if time_in_interval(time, interval):
return filename