speed up to_unix

wetb/gtsdf/unix_time.py

 from datetime import datetime, date
 import numpy as np
+timestamp0 = datetime.utcfromtimestamp(0)
 
 def to_unix(dateTime):
-    return (dateTime - datetime.utcfromtimestamp(0)).total_seconds()
+    #return dateTime.timestamp() + 3600
+    return (dateTime - timestamp0).total_seconds()
+    #return (dateTime - datetime.utcfromtimestamp(0)).total_seconds()
 
 
 def from_unix_old(sec):
@@ -32,4 +35,4 @@ def from_unix(sec):
             if du not in day_dict:
                 day_dict[du] = date.fromordinal(719163 + du).timetuple()[:3]
         y, m, d = zip(*[day_dict[d_] for d_ in d])
-        return ([datetime(*ymdhmsu) for ymdhmsu in zip(y, m, d, H.tolist(), M.tolist(), S.tolist(), ms.tolist())])
\ No newline at end of file
+        return ([datetime(*ymdhmsu) for ymdhmsu in zip(y, m, d, H.tolist(), M.tolist(), S.tolist(), ms.tolist())])