--- a/graph.py	Fri Dec 22 13:19:52 2017 +0100
+++ b/graph.py	Fri Dec 22 16:30:45 2017 +0100
@@ -59,6 +59,7 @@
     parser.add_argument('-s', '--start', help = 'Start date for graph (YYYY-MM-DD)', type = valid_date)
     parser.add_argument('-e', '--end', help = 'End date for graph (YYYY-MM-DD)', type = valid_date)
     parser.add_argument('-c', '--column', help = 'Column to plot (can be specified multiple times)', type = str, action = 'append')
+    parser.add_argument('-z', '--timezone', help = 'Timezone to operate in in (Oslon format) default: localtime)', type = str)
 
     args = parser.parse_args()
 
@@ -101,11 +102,15 @@
 
     # Get local timezone name and convert start/end to it
     # Why is this so hard...
-    ltname = tzlocal.get_localzone().zone
-    ltname = 'Australia/Adelaide'
-    lt = dateutil.tz.gettz(ltname)
+    if args.timezone is None:
+        args.timezone = tzlocal.get_localzone().zone
+
+    lt = dateutil.tz.gettz(args.timezone)
+    if lt == None:
+        parser.error('Unknown timezone')
+
     utc = dateutil.tz.gettz('UTC')
-    matplotlib.rcParams['timezone'] = ltname
+    matplotlib.rcParams['timezone'] = args.timezone
 
     if args.start.tzinfo == None:
         args.start = args.start.replace(tzinfo = lt)
@@ -115,15 +120,15 @@
     endlt = args.end
     args.start = args.start.astimezone(utc)
     args.end = args.end.astimezone(utc)
-    graph(args.graphfn, cur, cols, int(args.start.strftime('%s')), int(args.end.strftime('%s')), lt, utc)
+    graph(args.graphfn, cur, cols, args.start, args.end, lt, utc)
 
 def graph(fname, cur, _cols, start, end, lt, utc):
     import numpy
     import matplotlib
     import matplotlib.dates
 
-    startdt = datetime.datetime.fromtimestamp(start).replace(tzinfo = utc).astimezone(lt)
-    enddt = datetime.datetime.fromtimestamp(end).replace(tzinfo = utc).astimezone(lt)
+    startepoch = int(start.strftime('%s'))
+    endepoch = int(end.strftime('%s'))
 
     colourlist = ['b','g','r','c','m','y','k']
 
@@ -156,7 +161,7 @@
     for c in cols:
         # Get the data
         cur.execute('SELECT tstamp, ' + c.rowname + ' FROM ' + c.table + ' WHERE tstamp > ? AND tstamp < ? ORDER BY tstamp',
-                    (start, end))
+                    (startepoch, endepoch))
         ary = numpy.array(cur.fetchall())
         if ary.shape[0] == 0:
             print('No data for ' + c.rowname)
@@ -223,13 +228,13 @@
         ax1.text(0.02, 0.5, reduce(lambda a, b: a + '\n' + b, annotations),
                     transform = ax1.transAxes, bbox = dict(facecolor = 'blue', alpha = 0.5),
                     ha = 'left', va = 'top')
-    ndays = int(max(1, round((end - start) / 86400)))
+    ndays = int(max(1, round(((end - start).total_seconds()) / 86400)))
     for ax in fig.get_axes():
-        if (enddt - startdt).total_seconds() > 86400:
-            ax.set_title('%s to %s' % (startdt.strftime('%Y-%m-%d'), enddt.strftime('%Y-%m-%d')))
+        if ndays > 1:
+            ax.set_title('%s to %s' % (start.strftime('%Y-%m-%d'), end.strftime('%Y-%m-%d')))
         else:
-            ax.set_title('%s' % (startdt.strftime('%Y-%m-%d')))
-        ax.set_xlim([startdt, enddt])
+            ax.set_title('%s' % (start.strftime('%Y-%m-%d')))
+        ax.set_xlim([start, end])
         ax.format_xdata = lambda d: matplotlib.dates.num2date(d).strftime('%d %b %H:%M')
         ax.xaxis.grid(True)
         ax.xaxis.set_major_formatter(matplotlib.dates.DateFormatter('%d %b\n%H:%M'))