each day. The labels are placed exactly between two major grid lines
as they specify the complete day and not just midnight.
+[B<--week-fmt> I<strftime format string>]
+
+By default rrdtool uses "Week %V" to render the week number. With this option
+you can define your own format, without completely overriding the xaxis format.
+
=head2 Y-Axis
[B<-y>|B<--y-grid> I<grid step>B<:>I<label factor>]
the way RRDtool calculates its data. Some people favor a more 'organic' look
for their graphs even though it is not all that true.
-[B<-a>|B<--imgformat> B<PNG>|B<SVG>|B<EPS>|B<PDF>]
+[B<-a>|B<--imgformat> B<PNG>|B<SVG>|B<EPS>|B<PDF>|B<XML>|B<XMLENUM>|B<JSON>|B<JSONTIME>|B<CSV>|B<TSV>|B<SSV>]
Image format for the generated graph. For the vector formats you can
choose among the standard Postscript fonts Courier-Bold,
Helvetica-BoldOblique, Helvetica-Oblique, Helvetica, Symbol,
Times-Bold, Times-BoldItalic, Times-Italic, Times-Roman, and ZapfDingbats.
+For Export type you can define
+XML, XMLENUM (enummerates the value tags <v0>,<v1>,<v2>,...),
+JSON, JSONTIME (adds a timestamp to each data row),
+CSV (=comma separated values), TSV (=tab separated values), SSV (=semicolon separated values),
+(for comma/tab/semicolon separated values the time format by default is in the form of unix time. to change it to something else use: --x-grid MINUTE:10:HOUR:1:HOUR:4:0:"%Y-%m-%d %H:%M:%S")
+
[B<-i>|B<--interlaced>]
(this gets ignored in 1.3 for now!)