Changes in release 3.7.1:
* Updated makefiles and autoconf files
* Updated documentation and FAQ
* Added Windows stdin wrapper
* New drivers for Be, metapost, MacOS X Server
* Improved configuration of GNU readline support
* Security: the Linux SVGAlib driver is now disabled by default
* Support for GNU plotutils 2.2
* Improved tkcanvas driver (extend interactive capabilities, integrated
  perltk driver)
* Fixed compiling on IRIX 6.5, LynxOS 3.0.1
* Bug fix for negative aspect ratio
* Bug fixes in the cgm, eepic, png, and pslatex drivers
* Bug fix in the data fitting code (store value of last parameter)
* Bug fixes for HP-UX, NEXT, and Windows
* Bug fixes for save and set lmargin commands
* Bug fix for 'set view <z_scale>' (compressed z-axis) problem
* Bug fix for surface plots and negative ticslevel
* Bug fix for multiline labels
* Bug fix for multiplot and eps output
* Improved makefile for Amiga SAS/C
* Bug fixed with exit/quit in batch mode
* Return proper exit status
* Buffering bug in X11 driver fixed
* Added fitting of time series data
* Embedding document font is now default font in latex output
* Y2K: "%y" date format interpretation is now in line with
  Open Group recommendations
* Bugfix for logscale with unused y2 axis

What's new in 3.7 ?

from 315 to 348
  makefile.mgw contributed by HBB for compilation under MinGW32
  "-" means interactive on command line and load file
  gnuplot no longer faults on Alpha in prob.dem
  margin and label-positioning works with set ?label offset
  set ?tics auto resets the tic-marks
  line widths get copied in M$ Windows terminal when using the
     copy->clipboard option
  PSLATEX-terminal: resolves problems with german.sty when " is
     active character
  the terminal list gets paged through your preferred pager
  
  and many more.

See docs/old/ChangeLog.old and ChangeLog for a list of changes

  As always, there are outstanding contributed patches
 that I haven't yet installed (sorry), and half-promises for features
 that I've not had a chance to fulfill.

in this release (somwhere between 315 and 347)
  try to improve (and not break too badly) portability
  multiple X11 windows have number in window title, and active window
   has crosshair cursor

in 315
  suppress ! after a ! command in interactive mode
  address polar mode

314
  misc bug fixes

310
  HBB's hidden3d fix
  latest gnuplot.doc and term/*.trm help sections
  configure --with-gnu-readline[=path]

in 309
  sorry Roger ; os2 keeps on improving, but I forget to announce it
   {and often incorporate it !}
  relative errors displayed in fit

in 306
  histeps style
  LINE WIDTH PATCH !  {but many structures passed by value ?}
  tolerate missing closing backquote at end of line
  no limit on output filename
  set key samplelen / spacing
  plot ... axis   alias for  plot ... axes
  Thomas Koenig's postscript test for reencoding on the fly [at last]
  multiplot clear for djsvga
  size option on gif driver
  
in 300
  FINALLY moved the axes syntax over to plot ... axes x1y1 ...
  3d fitting ; FIT_INDEX no longer supported/needed (see fit.dem)
  added data columns -1 for line and -2 for index, for 3d fit
  had another go at the VPATH stuff for configure / make  

in 297
  back out unwanted feature of basing tics on relative size/font
  add financebars / candlesticks - size controlled by set bar
  plot 'file' using 0:1 gives x=0,1,... as gnuplot 3.5
  optional keyword 'font' in set xlabel 'text' dx,dy [font] "font,size"
  fix undefined points in splines

in 293/294
  ICCCM export of the x-window (allow paste into compliant apps ie NTRIGUE)
  print "string", expression, "string", ...
  set size square has been generalised to
    set size { square | ratio <r> | noratio }
    where <r> is an aspect ratio of height / width
  (at last) Hans-Bernhard Br"oker's changes, including fit fix and
    new hidden line removal routine
  plot line is commited to replot line at last possible moment, so
    that typos in complex plot do not ruin everything
  time routines separated into time.c - option to use system time
   routines instead of the gnuplot ones. Undocumented command
   testtime 'format' 'string'  to assist testing of time routines
  small changes to the terminal handling : hide details in term.c
  new shared makefile strategy : makefile.all


in 273
  pslatex driver takes solid/dashed
  cgm driver (ms-office applications ?)
  accept  using ::4  as shorthand for  using 1:2:4
  accept lp as abbreviation of linesp

in 268
  asinh() etc
  gnuplot -persist  and  set term x11 [reset] <n>
  gif terminal driver [not new in this release, but not mentioned before]

in 261
  compile on windows NT
  /end and /noend options in windows gnuplot
  first attempt at  timecolumn() and tm_sec() family of functions
  splot 'file' matrix

in 248 (?)
  try *again* to fix the postscript bounding box
  ALL TERMINALS UPDATED (thanks Stefan !)
  Continue to move help out of gnuplot.doc into terminal driver files (thanks Joerg)
  address problems with splines in log scales - NOTE that we take logs
   and then fit splines
  %T in gprintf prints as %d not %f hence no trailing .0000
  set locale  only affects LC_TIME (for the moment ?)
  make start optional in series tics, ie accept
    set [xyz]tics {start,}step{,end}
  also, if start or end not specified, treat as computed, and autoextend
    plot to a multiple of tics

in 242
  allow negative ticslevel
  geometric series tics for logscale
  enhanced sprintf format for tics - extra format characters available
    %x %o %e %f %g  %t %T %l %L %s %S %c
  take plot size and driver into account when choosing tics
  accept x1y2 etc in place of first/second
  extra line in boxed key
  x2 label
  fonts for label
  strftime format for 'set time'
  more timeseries patches
  set locale
  try to fix postscript bounding box

in 224
  set clabel ['format']
  pstexdriver
  set encoding
  enhpost moved into post.trm
  index a:b:c for splot

in 194
  multiplot for splot

in 188
  os9 port
  set xrange [] reverse writeback
  allow mix of co-ordinate systems within an arrow/label posn
  initial multiplot support
  - doesn't yet check that terminal is capable, but there is a
    flags field added to the terminal entry to tell gnuplot about this.
    also, suspend() / resume() entry points which are to be called
    between plots of a multiplot.

in 178
   arbitrary length/number of columns in datafile
   accept double/quad-precision fortran numbers (1.23{dDqQ}4)
   - but not in scanf format string
   undefined fit parameters start at 1 rather than 1e-30
   - more chance of convergence / less change of unitary matrix
   WIN32 / Win-NT support
   table output can be read back in for data splot
   - hence gnuplot can be used to dgrid a datafile and write it out
   set missing 'string'
   - nominate a token as standing for missing values in datafile
   - not yet added to documentation
   updates to time-series stuff (so it doesn't break at 2000)
   - except it has become horribly non-portable :-(
   split graph3d.c into util3d.c and hidden3d.c

in 166
   set bar <size>
   - a number rather than just small or large
   allow different linetypes for grid at major and minor tics
   a few more set no* commands for consistency.
   initial go at implementing tic mirrors and axes for splot
   - no ztic axis yet (or no zzeroaxis)
   - tics on axes are not hidden by surface
   attempt to make sin(x) behave as expected when set angle degrees
   - gives answers if x is complex, but I dont know if they are correct
     - acos(cos(x)) seems to give x, so at least its consistent
   - fix a bug which made acos(cos({0,1})) undefined
   new grass.trm

in release 162/164
   set size [{no}square] x,y  - tries to plot with aspect ratio 1
   - seems to work great for postscript
   - please check with your favourite driver
   - uses relative sizes of tics to determine required size.
   posn for key, labels and arrows can be in one of 4 co-ordinate systems
   - first_axes (default)
   - second_axes (for plot..second)
   - graph  (0,0 -> 1,1 = plotting area)
   - screen (0,0 -> 1,1 = whole screen)
   - arrows needn't have endpoints in same co-ords. see help set label
   via is now a required keyword for fit
   - fit f(x) 'file' ... via { 'file' | a,b,... }
   - this is to avoid confusing 'file' with 'using-format-string'
   win32 and 16-bit dos fixes
   - I can compile with tc++, but get an overlay error at runtime.
   new set of documentation programs (I haven't tried them)
   various tweaks to makefile
   changes to pslatex
   - substitute .ps at _last_ . in filename 
   - accept font size of enclosing document as an option.
   - dont forget to close aux file

in release 151

  linux security patch
  can specify font for labels, etc (postscript only ? - I haven't tried this)
  can specify linetype to draw grid / zeroaxes / arrows
  emx terminal driver
  first attempt at pipes for VMS and vector style - needs more work
  l/b/r/t-margin  in place of xmargin - more control over size of margins
  incompatible changes to polar mode:
  - t is now the dummy variable, so x is width of plot as expected
  - tics are not automatically on axes -   set {xy}tics axis nomirror
  - grid is not automatically polar - set grid x [mx] polar [angle]
  - no numbers on grid - they were always in degrees
  second axes
  - x2 and y2 are an independent pair of axes, but they inherit
    ranges from x and y if no second data
    - there can be problems with this, actually - if x2tics are not
      shown, x2range is not autoextended to whole number of tics, so
      same data might not have same range.
  - set x2tics/y2tics/x2label/y2label
  - set [no]log x2 / y2
  - plot [first,] f(x), 'file', ..., second, g(x), ...
  - get specify grid at any/all of x,y,x2,y2
  - see electron.dem
  set border <mask> - 12 bit binary number selects 12 sides of cube around splot
  can specify grid z, to get a grid on back wall of splot
  set mxtics [<interval>|default] | set nomxtics
  - set mxtics  gives auto for logscale, fixed for linear 
  binary, index and every keywords to datafiles.
  - every also works with binary files
  can use '-' as datafile for inline data (ends at line with e)
  can use '' to mean reuse previous file
  splot and fit now use datafile module
  - FIT_SKIP no longer supported - use fit f(x) 'file' every n
  can limit fit range using   fit [variable=min:max] f(variable) ...
  set ticscale <major> [<minor>]
  surface is clipped with no hidden line removal
  - still to do contour and hidden-line surface
  set {x|y|x2|y2} [axis|border] [no]mirror
  - can put tics on border or axes
  - mirror controls mirroring of tics on opposite axis
    - no longer coupled to  set tics out  setiing.
  No longer need to specify parametric mode for 3-column data files.
  ranges automatically extended to whole number of tic intervals
  - doesn't always manage to drop vertical from surface to corner of base
    - workaround is either specify range or use  set border

patchlevel 140
--------------
I've probably missed a lot of features since I'm so used to them.
Plus I never bothered with 3.5 so some of these may have been there.
some of these may have made it into the documentation
Here goes:

  fit f(x) 'file' via ...
  read and plot time data  (timedat.dem)
  set key [top|bottom|under] [left|right|out] [reverse] [box [<linetype>]]
  set key title 'text'
  Processing of escape sequences in "strings" but not 'strings'
  - TeX users in particular advised to use ''
  Multiline labels, etc, using "first\nsecond"
  enhpost driver
  call command (load with parameters)
  x error bars. splines. boxes. [some may have been in 3.5]
  pipes for amiga
  the using patch   plot 'file' using spec:spec:...
  - spec is either column number or (expression in $1, $2, ...)
  new pslatex driver with postscript to aux file.
  set pointsize <scale factor> on some terminals
  doubles in  plot...using  format string - %lf
  unlimited input line length and expression (action) table
  minor tic-marks (like logscale but also for linear)
  - also set grid [mx|my]



that's all I can think of for the moment...


 o timeseries plots
 o enhanced X11 driver
 o Win32/NT support
 o OS9 support
 o updated copyright
 o new driver: NeXT
 o window option for Amiga driver
 o greatly improved hidden3d algorithm
 o updated postscript docs (Dick)
 o multiplot feature
 o new driver: texdraw
 o new driver: gif (requires external lib)
 o new driver: emx
 o pipe support for Amiga
 o using patch (dd)
 o enhanced postscript driver (Matt Heffron)
 o integration of Carsten Grammes's gnufit extension
 o greatly improved configuration on Unix platforms
 o fig driver updated to xfig 3.x
 o new driver: Linux svga
 o improved pslatex driver
 o new hpgl driver hp7550
 o new errorbar styles
