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Package graph-plotlim (in graph.i) - plot limits and axis scaling

Index of documented functions or symbols:


DOCUMENT gridxy, flag
      or gridxy, xflag, yflag
  Turns on or off grid lines according to FLAG.  In the first form, both
  the x and y axes are affected.  In the second form, XFLAG and YFLAG
  may differ to have different grid options for the two axes.  In either
  case, a FLAG value of 0 means no grid lines (the default), a value of
  1 means grid lines at all major ticks (the level of ticks which get
  grid lines can be set in the style sheet), and a FLAG value of 2 means
  that the coordinate origin only will get a grid line.  In styles with
  multiple coordinate systems, only the current coordinate system is
  The keywords can be used to affect the style of the grid lines.

  You can also turn the ticks off entirely.  (You might want to do this
  to plot your own custom set of tick marks when the automatic tick
  generating machinery will never give the ticks you want.  For example
  a latitude axis in degrees might reasonably be labeled "0, 30, 60,
  90", but the automatic machinery considers 3 an "ugly" number - only
  1, 2, and 5 are "pretty" - and cannot make the required scale.  In
  this case, you can turn off the automatic ticks and labels, and use
  plsys, pldj, and plt to generate your own.)
  To fiddle with the tick flags in this general manner, set the
  0x200 bit of FLAG (or XFLAG or YFLAG), and "or-in" the 0x1ff bits
  however you wish.  The meaning of the various flags is described
  in the file Y_SITE/gist/  Additionally, you can use the
  0x400 bit to turn on or off the frame drawn around the viewport.
  Here are some examples:
     gridxy,0x233 default setting
     gridxy,,0x200       like, but no y-axis ticks or labels
     gridxy,,0x231       like, but no y-axis ticks on right
     gridxy,0x62b default setting

  The three keywords base60=, degrees=, and hhmm= can be used to get
  alternative tick intervals for base 60 systems instead of the
  usual base 10 systems.  The keyword values are 0 to restore the
  default behavior, 1 to set the feature for the x axis, 2 to set it
  for the y axis, and 3 to set it for both axes.  The base60 feature
  allows ticks and labels at multiples of 30 (up to +-3600).  The
  degrees feature causes labels to be printed modulo 360 (so that a
  scale which runs from, say, 90 to 270 will be printed as 90 to 180
  then -180 to -90, mostly for longitude scales).  The hhmm feature
  causes labels to be printed in the form hh:mm (so that, for example,
  150 will be printed as 02:30, mostly for time of day scales).

KEYWORDS: color, type, width, base60, degrees, hhmm

SEE ALSO: window, plsys, limits, range, logxy, viewport


      or limits, xmin, xmax, ymin, ymax,
                 square=0/1, nice=0/1, restrict=0/1
      or old_limits= limits()
      or limits, old_limits

  In the first form, restores all four plot limits to extreme values.

  In the second form, sets the plot limits in the current coordinate
  system to XMIN, XMAX, YMIN, YMAX, which may be nil or omitted to
  leave the corresponding limit unchanged, a number to fix the
  corresponding limit to a specified value, or the string "e" to
  make the corresponding limit take on the extreme value of the
  currently displayed data.

  If present, the square keyword determines whether limits marked
  as extreme values will be adjusted to force the x and y scales
  to be equal (square=1) or not (square=0, the default).
  If present, the nice keyword determines whether limits will be
  adjusted to nice values (nice=1) or not (nice=0, the default).
  There is a subtlety in the meaning of "extreme value" when one
  or both of the limits on the OPPOSITE axis have fixed values --
  does the "extreme value" of the data include points which
  will not be plotted because their other coordinate lies outside
  the fixed limit on the opposite axis (restrict=0, the default),
  or not (restrict=1)?

  If called as a function, limits returns an array of 5 doubles;
  OLD_LIMITS(1:4) are the current xmin, xmax, ymin, and ymax,
  and int(OLD_LIMITS(5)) is a set of flags indicating extreme
  values and the square, nice, restrict, and log flags.

  In the fourth form, OLD_LIMITS is as returned by a previous
  limits call, to restore the limits to a previous state.

  In an X window, the limits may also be adjusted interactively
  with the mouse.  Drag left to zoom in and pan (click left to zoom
  in on a point without moving it), drag middle to pan, and click
  (and drag) right to zoom out (and pan).  If you click just above
  or below the plot, these operations will be restricted to the
  x-axis; if you click just to the left or right, the operations
  are restricted to the y-axis.  A ctrl-left click, drag, and
  release will expand the box you dragged over to fill the plot
  (other popular software zooms with this paradigm).  If the
  rubber band box is not visible with ctrl-left zooming, try
  ctrl-middle or ctrl-right for alternate XOR masks.  Such
  mouse-set limits are equivalent to a limits command specifying
  all four limits EXCEPT that the unzoom command can revert to
  the limits before a series of mouse zooms and pans.

  Holding the shift key and pressing the left mouse button is
  equivalent to pressing the middle mouse button.  Similarly,
  pressing meta-left is equivalent to the right button.  This
  permits access to the middle and right button functions on
  machines (e.g.- most laptops) with two button or one button

  The limits you set using the limits or range functions carry over
  to the next plot -- that is, an fma operation does NOT reset the
  limits to extreme values.

SEE ALSO: plsys, range, logxy, zoom_factor, unzoom, plg, viewport


DOCUMENT logxy, xflag, yflag
  sets the linear/log axis scaling flags for the current coordinate
  system.  XFLAG and YFLAG may be nil or omitted to leave the
  corresponding axis scaling unchanged, 0 to select linear scaling,
  or 1 to select log scaling.

SEE ALSO: plsys, limits, range, plg, gridxy


DOCUMENT range, ymin, ymax
  sets the y-axis plot limits in the current coordinate system to
  YMIN, YMAX, which may be nil or omitted to leave the corresponding
  limit unchanged, a number to fix the corresponding limit to a
  specified value, or the string "e" to make the corresponding limit
  take on the extreme value of the currently displayed data.
  Use    limits, xmin, xmin
  to accomplish the same function for the x-axis plot limits.

SEE ALSO: plsys, limits, logxy, plg


  restores limits to their values before zoom and pan operations
  performed interactively using the mouse.
  Use    old_limits=  limits()
         limits, old_limits
  to save and restore plot limits generally.

SEE ALSO: limits, range, zoom_factor, plg


DOCUMENT zoom_factor, factor
  sets the zoom factor for mouse-click zoom in and zoom out operations.
  The default FACTOR is 1.5; FACTOR should always be greater than 1.0.

SEE ALSO: limits, range, unzoom, plg