# coyote: CGZPLOT

- [Source code]

Description

      This program creates a "zoomable" line plot in an interactive window. The user can
      zoom into or out of the plot. Once a plot is zoomed, the user can then pan the plot
      in both the X and Y directions. See the operating instructions for how to interact
      with the line plot.
      .. image:: cgzplot.png
      Operating Instructions--
      Use the LEFT mouse button to zoom the plot and the RIGHT mouse button to pan the plot.
      If you click and drag inside the plot axes, you will create a rubber band box. Select the
      portion of data you wish to zoom into. The zoom will occur in both the X and Y directions.
      If you wish to zoom the plot all the way back out, simply click and release the LEFT mouse
      button inside the plot axes without moving the mouse.
      Once you are zoomed into a plot, you can adjust the zoom by clicking the LEFT mouse button
      outside the plot axes. If you click the mouse below the plot, you will cause the X axis to
      zoom out of the plot by the zoomFactor amount (normally 5% of the current range of the axis).
      If you wish to zoom the X axis into the plot, simply click above in the region of the window
      above the plot. Click below the plot to zoom out, above the plot to zoom in. Similarly, you
      can adjust the zoom on the Y axis. Clicking to the left of the plot zooms the Y axis out,
      while clicking to the right of the plot zooms the Y axis in.
      If you are zoomed into the plot, you can pan to different locations in the plot by using
      the RIGHT mouse button. Hold and drag the RIGHT mouse button inside the plot axes. The
      entire plot will pan in both the X and Y directions.
      File output requires that ImageMagick and GhostScript be installed on your machine. Note
      that exact axis scaling is always in effect.

Params

      x: in, required, type=any
           If X is provided without Y, a vector representing the dependent values to be
           plotted If both X and Y are provided, X is the independent parameter and
           Y is the dependent parameter to be plotted.
      y: in, optional, type=any
           A vector representing the dependent values to be plotted.

Keywords

      aspect: in, optional, type=float, default=none
         Set this keyword to a floating point ratio that represents the aspect ratio
         (ysize/xsize) of the resulting plot. The plot position may change as a result
         of setting this keyword.
      err_clip: in, optional, type=boolean, default=1
         Set this keyword to cause error bars to be clipped to the borders of the plot.
         The default is to clip the error bars to the extent of the zoomed plot.
      err_color: in, optional, type=varies
         The color error bars should be drawn in. The default is to use the `Color` keyword.
      err_thick:, in, optional, type=integer
         The thickness of the line for drawing the error bars. By default, !P.Thick.
      err_width: in, optional, type=float
         The width of the end lines on error bars in normalized coordinates. By default, the
         width is one percent of the width of the axes length in the appropriate dimension.
      err_xhigh: in, optional
          he high error values that should be added to the independent or X data values.
      err_xlow: in, optional
         The low error values that should be subtracted from the independent or X data values.
      err_yhigh: in, optional
         The high error values that should be added to the dependent or Y data values.
      err_ylow: in, optional
         The low error values that should be subtracted from the dependent or Y data values.
      label: in, optional, type=string
         A label is similar to a plot title, but it is aligned to the left edge
         of the plot and is written in hardware fonts. Use of the label keyword
         will suppress the plot title.
      legends: in, optional, type=object
         A single cgLegendItem object, or an array of cgLegendItem objects that will be
         drawn on the plot as a legend.
      max_value: in, optional, type=float
         Set this keyword to the maximum value to plot. Any values greater than this
         value are treated as missing.
      min_value: in, optional, type=float
         Set this keyword to the minimu value to plot. Any values smaller than this
         value are treated as missing.
      oplots: in, optional, type=object
         A single cgOverPlot object, or an array of cgOverPlot objects that will be
         overplot on the axes set up by the original data.
      parent: in, optional, type=long
         The identifer of the parent widget for this program's draw widget. If not
         provided, the program will create it's own top-level base widget as a parent.
      symcolor: in, optional, type=string/integer, default='black'
         If this keyword is a string, the name of the symbol color. By default, 'black'.
         Otherwise, the keyword is assumed to be a color index into the current color table.
      xlog: in, optional, type=boolean, default=0
         Set this keyword to use a logarithmic X axis
      xrange: in, optional, type=double
         Set this keyword to a two-element array giving the X data range of the plot.
      xsize: in, optional, type=int, default=640
         The X size of the program's draw widget.
      ylog: in, optional, type=boolean, default=0
         Set this keyword to use a logarithmic Y axis
      ynozero: in, optional, type=boolean, default=0
         Set this keyword to use allow the Y axis to start at a value other than zero.
      yrange: in, optional, type=double
         Set this keyword to a two-element array giving the Y data range of the plot.
      ysize: in, optional, type=int, default=512
         The Y size of the program's draw widget.
      zoomfactor: in, optional, type=float
         Set this keyword to a number between 0.01 and 0.25. This affects the amount
         of zooming when the X axis and Y axis are zoomed with the LEFT mouse button.
         The default value is 0.05 or five percent of the current axis range on each
         end of the axis, resulting in a 10 percent change in the axis length.
      _ref_extra: in, optional, type=any
         Any keyword appropriate for the IDL Plot or Coyote Graphic cgPlot command is
         allowed in the program. Note that this is not the same as saying it is a good
         idea to use every one of the these keywords. Use good judgment.

Examples

      Use as you would use the cgPlot command::
         cgZPlot, cgDemoData(1)
         cgZPlot, cgDemoData(1), Aspect=1.0
         cgZPlot, cgDemoData(1), Color='olive', AxisColor='red', Thick=2
         cgZPlot, cgDemoData(1), Color='blue', SymColor='red', PSym=-16
       Example using error bars::
         data = Congrid(cgDemoData(1), 15)
         seed = -5L
         time = cgScaleVector(Findgen(N_Elements(data)), 1, 9)
         high_yerror = RandomU(seed, N_Elements(data)) * 5 > 0.5
         low_yerror = RandomU(seed, N_Elements(data)) * 4 > 0.25
         high_xerror = RandomU(seed, N_Elements(data)) * 0.75 > 0.1
         low_xerror = RandomU(seed, N_Elements(data))  * 0.75 > 0.1
         xtitle = 'Time'
         ytitle = 'Signal Strength'
         title = 'Error Bar Plot'
         position = [0.125, 0.125, 0.9, 0.925]
         thick = (!D.Name EQ 'PS') ? 3 : 1
         cgZPlot, time, data, Color='red5', PSym=-16, $
             SymSize=1.0, Thick=thick, Title=title, XTitle=xtitle, YTitle=ytitle, $
             Position=position, YStyle=1, $
             ERR_XLow=low_xerror, ERR_XHigh=high_xerror, ERR_CLIP=1, $
             ERR_YLow=low_yerror, ERR_YHigh=high_yerror, ERR_Color='blu5'

Author

      FANNING SOFTWARE CONSULTING::
         David W. Fanning
         1645 Sheely Drive
         Fort Collins, CO 80526 USA
         Phone: 970-221-0438
         E-mail: david@idlcoyote.com
         Coyote's Guide to IDL Programming: http://www.idlcoyote.com

Copyright

      Copyright (c) 2012, Fanning Software Consulting, Inc.

History

      Change History::
         Separated the object code (cgZPlot__Define) from this driver code for easier inheritance. 14 June 2012. DWF.
         Added LABEL keyword. 12 July 2012. DWF.