2007 Mar 15: PyXPlot 0.6.3.1
   - Minor bugfix so that gv will work with -watch.

2007 Feb 26: PyXPlot 0.6.3
	- Manual updated
	- Some minor bugfixes

2007 Jan 19: PyXPlot 0.6.2
	- 'enlarge' terminal option implemented.
	- pdf terminal implemented.
	- set preamble command implemented.
	- LaTeX preambles bugfixed, so that the '\usepackage' command can now be
	  used.
	- 'X11_persist' terminal bugfixed to work correctly from non-interactive
	  sessions.
	- Large number of minor bugfixes.

2006 Dec 27: PyXPlot 0.6.1
	- Major bug-fixes to the set and unset commands.
	- Command reference chapter added to User Manual.
	- Command syntax references added to the help command system.
	- 'text' and 'set label' commands extended to allow rotation of text
	  through arbitrary angles.
	- Semi-functional 'jpeg' and 'eps' commands added. Left undocumented
	  because they're unstable and need a bit of work.

2006 Nov 12: PyXPlot 0.6.0
	- New more-reliable command parser implemented, with improved syntax
	  errors.
	- delete_arrow, delete_text, undelete_arrow, undelete_text and move_text
	  commands removed from API. The move, delete and undelete commands now act
	  on all kinds of multiplot object.
	- set terminal command no longer recognised enhanced and noenhanced
	  keywords. The postscript and eps terminal keywords should now be used in
	  their place.
	- Automatic ticking of axes overhauled, and the set xtics and set mxtics
	  commands implemented for those who do not like the default ticking
	  schemes.
	- set log and set nolog command now allow axes to work with log bases other
	  than 10.
	- The select modifier after the plot, fit, replot and spline commands can
	  now only be used once; to specify multiple select criteria, use the and
	  logical operator.
	- X11_persist terminal implemented.
	- Requirement on python 2.4 eased to python 2.3.
	- Requirements on scipy and readline eased; PyXPlot will now work in
	  reduced form without them.
	- Requirements on dvips and gs are dropped; postscript handling now done by
	  PyXPlot itself.

2006 Sep 09: PyXPlot 0.5.8
	- Many bugfixes to error trapping and reporting.

2006 Aug 26: PyXPlot 0.5.7
	- set display command implemented.
	- set keycolumns command implemented.
	- CTRL-C behaviour changed; no longer quits PyXPlot.
	- plot '*.dat' now arranges files alphabetically.
	- Escaping of LaTeX < and > symbols fixed.
	- Major bugfix to fit command's error estimation.
	- Major bugfix to the positioning of legends in the "outside" and "below"
	  positions to avoid overlapping with axes.
	- help command text substantially revised.

2006 Aug 18: PyXPlot 0.5.6
	- Ability to unset variables via "a=" implemented.
	- Handling on scipy error messages in the int_dx and spline commands
	  improved.
	- Colour-highlighted terminal added.
	- The inline help system made much more complete.
	- select modifier implemented.
	- set texthalign and set textvalign implemented.
	- set xticdir command implemented.
	- Support for CSV input datafiles implemented.
	- pyxplot_watch quiet mode added. Also, behaviour changed to allow the
	  watching of files, even when they do not initially exist.
	- Labels can now be placed on "nolabels", "nolabelstics" and "invisible"
	  axes. Example 10 changed to demonstrate this.
	- set log, when issued on its own, now applies to all axes, rather than
	  throwing an error.

2006 Jul 25: PyXPlot 0.5.5
	- pyxplot_watch implemented.
	- fit command now gives error estimates, as well as correlation matrices.
	- Many new pointtypes added, including upper and lower limit symbols.
	- Handling of SIGINT improved; now exits current command in interactive
	  mode, and exits PyXPlot when running a script.
	- Quote characters can now be escaped in LaTeX strings, to allow strings
	  with both ' and " characters to be rendered.
	- Installer no longer creates any files belonging to root in the user's
	  homespace.
	- show xlabel and show xrange implemented.
	- Bug fix: cd command no longer crashes if target directory doesn't exist.
	- Bug fix: some commands, e.g. plot, which previously didn't work when
	  capitalised, now do.
	- Major bug fix to int_dx and diff_dx functions.

2006 Jul 3: PyXPlot 0.5.4
	- edit command implemented.
	- Numerical integration and differentiation functions implemented.
	- New makefile installer added.
	- man page added.
	- Brief tour of gnuplot syntax added to documentation.
	- Many minor bug fixes.

2006 Jun 27: PyXPlot 0.5.3
	- set bar and set palette implemented.
	- Stacked barcharts implemented.
	- Command history files and the save command implemented.
	- Plotting of functions with errorbars implemented.
	- Ability to define a LaTeX preamble implemented.
	- Bug fix to smoothed splines, to ensure that smoothing is always applied
	  to a sensible degree by default.
	- Bug fix to the autoscaling of bar charts, histograms and errorbars, to
	  ensure that their full extent is contained within the plot area.
	- Bug fix to arrow plotting, to prevent PyX from crashing if arrows of zero
	  lengths are plotting (they have no direction...)

2006 Jun 14: PyXPlot 0.5.2
	- spline command, and csplines/acsplines plot styles implemented.
	- Syntax plot[0:1], with no space, now allowed.
	- Automatic names of datasets in legends no longer have full paths, but
	  only the path in the form that the user specified it.
	- Bug fix to the handling of LaTeX special characters in the automatic
	  names of datasets, e.g. file paths containing underscores.
	- Error messages now sent to stderr, rather than stdout.
	- multiplot mode now plots items in the order that they are plotted;
	  previously all arrows and text labels had been plotted in front of plots.
	- set backup command implemented, for keeping backups of overwritten files.
	- Bug fix, enabling the use of axis x5 without axis x3, and likewise for y.
	- unset axis command implemented, for removing axes from plots.
	- 'invisible', 'nolabels', and 'nolabelsticks' axis title implemented, for
	  producing axes without text labels.
	- plot 'every' modifier re-implemented, to use the same syntax as gnuplot.
	- fit command re-implemented to work with functions of > 1 variable.
	- plot with pointlines defined as alias for 'linespoints'.
	- plot using rows syntax implemented, for plotting horizontally-arranged
	  datafiles.
	- Bug fix to replot command in multiplot mode, to take account of any move
	  commands applied to the last plot.
	- Bug fix to errorbar pointsizes. pointsize modifier now produces sensible
	  output with all errorbar plot styles.
	- show command re-implemented to accept any word that the set command will.

2006 Jun 2: PyXPlot 0.5.1
	- Pling and cd commands implemented; ` ` shell command substitution
	  implemented.
	- Arrows (both from set arrow and the arrow command) can now have linetypes
	  and colours set.
	- Colours can now be specified as either palette indices or PyX colour
	  names in all contexts -- e.g. 'plot with colour red'.
	- Function plotting fixed to allow plotting of functions which are not
	  valid across the whole range of the x-axis.
	- Transparent terminals now have anti-aliasing disabled.
	- Warnings now issued when too many columns are specified in plot command;
	  duplicate errors filtered out in two-pass plotting.
	- Function splicing implemented.
	- Documentation: sections on barcharts, function splicing, and datafile
	  globbing added.

2006 May 27: PyXPlot 0.5.0
	- Name changed to PyXPlot.
	- Change to distribution format: PyX Version 0.9 now ships with package.
	- Safety installer added; checks for required packages.
	- 'errorrange' plot styles added; allow errorbars to be given as min/max
	  values, rather than as a standard deviation.
	- 'boxes', 'wboxes', 'steps', 'fsteps', 'histeps' and 'impulses' plot
	  styles implemented -- allow the production of histograms and bar charts.
	- plot with fillcolour implemented, to allow coloured bar charts.
	- Handling of broken datafiles sanitised: now warns for each broken line.
	- gridlines on multiple axes, e.g. 'set grid x1x2x3' now allowed.
	- Major bugfix to the way autoscaling works: linked axes share information
	  and scale intelligently between plots.
	- --help and --version commandline options implemented.
	- 'using' specifiers for datafiles can now include expressions, such as
	  $(2+x).
	- eps terminal fixed to produce encapsulated postscript.
	- datafile names now glob, so that plot '*' will plot many datafiles.
	- Documentation: examples 6,7 and 8 added.

2006 May 18: GnuPlot+ 0.4.3
	- text and arrow commands now accept expressions rather than just floats
	  for positional coordinates.
	- clear command major bug-fixed.
	- 'plot with' clause bugfixed; state variable was not resetting.
	- Automatical key titles for datafile datasets made more informative.
	- Autoscaling of multiple axes bugfixed.
	- Autoscaling of inverted axes fixed.
	- set grid command fixed to only produce x/y gridlines when requested.
	- X11_singlewindow changed to use gv --watch.
	- landscape terminal postscript header detection bugfixed.
	- noenhanced terminal changed to produce proper postscript.
	- Plotting of single column datafiles without using specifier fixed.

2006 May 4: GnuPlot+ 0.4.2
	- Autoscaling redesigned, no longer uses PyX for this.
	- Numerical expression handling fixed in set title, set origin and set
	  label.
	- Handling of children fixed, to prevent zombies from lingering around.
	- arrow command implemented.
	- set textcolour, set axescolour, set gridmajcolour, set gridmincolour
	  and set fontsize implemented.
	- Colour palette can now be set in configuration file.
	- Ranges for axes other then x1/y1 can now be set in the plot command.
	- Postscript noenhanced can now produce plots almost as big as an A4 sheet.
	- Plotting of one column datafiles, against datapoint number, implemented.
	- Negative errorbars error trapped.
	- Comment lines now allowed in command files.

2006 May 1: GnuPlot+ 0.4.1
	- Documentation converted from ASCII to LaTeX.
	- ChangeLog added.
	- Configuration files now supported.
	- Prevention of temporary files in /tmp overwriting pre-existing files.
	- set term enhanced / noenhanced / landscape / portrait / png / gif / jpeg
	  / transparent / solid / invert / noinvert implemented.
	- set dpi implemented, to allow user to choose quality of gif/jpg/png
	  output.
	- `set grid' command now allows user to specify which axes grid attaches
	  to. (extended API)
	- Support introduced for plotting gzipped datafiles. Filenames ending in
	  '.gz' are assumed to be gzipped.
	- load command implemented.
	- move command implemented.
	- Long lines can now be split using '\' linesplit character at the end of a
	  line. Any whitespace at the beginning of the next is omitted.
	- text / delete_text / undelete_text / move_text commands implemented.
	- refresh command implemented. (extended API)
	- point types, line styles, and colours now start at 1, for gnuplot
	  compatibility.
	- default terminal changed to postscript for non-interactive sessions.

2006 Apr 27: GnuPlot+ 0.4.0
	- Bug fix: now looks for input scripts in the user's cwd, not in /tmp.
	- 'set logscale' is now valid syntax (as in gnuplot), as well as 'set log'.
	- multiplot implemented, including linked axes, though with some brokenness
	if linked axes are allowed to autoscale.
	- 'dots' plotting style implemented.
	- Bug fix: can now include a plot 'with' clause after an 'axes' clause;
	could not previously without an error message arising.
	- Pointstyles now increment between plotted datasets, even in a colour
	terminal where the colours also increment.
	- garbage collection of .eps files from the X11 terminal added. Previously
	they were left to fester in /tmp.
	- pointlinewidth added as a plot style, specifying the linewidth to be used
	in plotting points. 'set plw' and 'set lw' both added (extended API).
	- delete, clear and undelete commands added to the multiplot environment.
	- unset command implemented.
	- set notitle implemented.

2006 Apr 14: GnuPlot+ 0.3.2
	- The autoscaling of logarithmic axes made more trust-worthy: error checks
	to ensure that they do not try to cover negative ordinates.
	- Error checks put in place to prevent empty keys being plotted, which made
	PyX crash previously. Now can plot empty graphs happily.
	- Datasets with blank titles removed from the key, to allow users to plot
	some datasets to be omitted from the key. This is not possible in gnuplot.
	- Bug fix to prevent PyX's texrunner from crashing irreparably upon
	receiving bad LaTeX. Now uses a spanner to attempt to return it to working
	order for the next plot.
	- Bug fix to the autoscaling of axes with no range of data -- previous did
	not work for negative ordinates. Now displays an axes with a range of +/-
	1.0 around the data.

2006 Apr 12: GnuPlot+ 0.3.1
	- Plotting of functions fixed: plot command will now plot any algebraic
	expression, not just functions of the form f(x).
	- Space added after command prompt.

2006 Apr 12: GnuPlot+ 0.3.0
	- X11_singlewindow and X11_multiwindow terminals implemented, as distinct
	from just standard X11.
	- Key positioning allowed to be xcentre, ycentre, below and outside, as
	well as in the corners of the plot. Key allowed to be offseted in position.
	- Datasets colours can be set via 'plot with colour <n>'
	- Datasets are split when there is a blank line in the datafile; lines are
	not joined up between the two segments.
	- set size implemented; can now change aspect ratio of plots.
	- working directory of GnuPlot+ changed to /tmp, so that LaTeX's temporary
	files are stored there rather than in the user's cwd.

2006 Mar 30: GnuPlot+ 0.2.0
	- Standard GnuPlot dual axes improved upon, allowing users to add x3, x4
	axes, etc, up to any number of axes that may be desired.
	- Autocomplete mechanism for commandline substantially cleaned up and
	debugged.
	- Bug fixes to the plotting of arrows/labels. Now appear *above* gridlines,
	not below.

2006 Feb 26: GnuPlot+ 0.1.0