Time-series graph
tsgraph yvarlist [if exp] [in range] [ , graph_options nlabel(#) ]
Description
tsgraph plots one or more y variables against whatever tsset knows as the time variable. It is a convenience graph with options built-in to plot time series as connected lines. Data must have been tsset previously.
tsgraph looks for a panel variable and identifies distinct panels whenever there are no more than 4.
Remarks
Whenever
the time variable has a %t or %d format, and
neither xlabel nor xlabel() is specified, and
values span more than one year
tsgraph attempts to select for the time (x) axis nice labels based on the years included in the time series. For daily, weekly, monthly, quarterly or half-yearly data, it attempts to show the first time period within each of various years which are nice numbers. For yearly data, it attempts to show years which are nice numbers. Nice numbers here are preferably multiples of 10, 5 or 2. The main algorithm used is based on code by Hardin (1995).
Options
graph_options are options allowed with graph, twoway. Defaults are
connect(L), connect(LL[_]), connect(LL[_]L[-]), connect(LL[_]L[-]L[.]) for 1, 2, 3, 4 y variables
symbol is i for each y variable
xlabel ylabel gap(4)
l2title("(log scale)") if ylog
l1title shows variable label or variable name of single y variable.
nlabel(#) suggests the number of nice labels to be shown on the time axis. The suggestion may or may not be taken literally. This option is independent of xlabel or xlabel().
Examples
. tsset year
. tsgraph GDP*
Authors
Nicholas J. Cox, University of Durham, U.K. n.j.cox@durham.ac.uk Christopher F. Baum, Boston College baum@bc.edu
Acknowledgements
Alan Riley made a very helpful suggestion.
References
Hardin, J.W. 1995. Calculate nice numbers for labeling or drawing grid lines. Stata Technical Bulletin 25, 2-3. (Also in STB Reprints Volume 5, 19-20.)
Also see
On-line: help for graph, tsset, dfmt, tfmt