Preferences

The Preferences... item in the Edit menu, brings up a dialog box in which one can set the default display behavior for new graphs. One can control the tick frequency, grid line colors, and scaling for graph axes; color, point styles, and line types for scatter plots; and colormaps and scaling of images. The window has a paned format in which the options affecting each part of the graph has a pane which can be brought forward by clicking the appropriately labeled tab.

  • POW
    
         This pane sets the application level preferences for how POW
         looks and behaves.  Cursor sets the image to use as the
         mouse cursor when in POW's main window.  POW's "GUI" consists of
         the 3 pixel readouts, the Scopebox, and the Zoom In/Out buttons
         usually located at the top of the window.  The GUI
         Position option allows you to move these to any side of the
         window or turn them off altogether.  Scopebox Size alters
         the size of the scopebox -- the window showing a small overview
         of the current graph -- or hides it altogether.  Resize
         Window determines whether the POW window will get bigger or
         smaller (as far as possible) whenever you change the objects in
         the main POW window, so as to show you everything currently
         displayed in the main POW window without scrolling.
         Using the color grid or button, Background Color will set
         the color to use for the background of all of POW's windows.
  • Graph
    
         This pane has been modified, containing a pair of entry
         boxes labeled Size, a set of buttons labeled
         Scaling and new control to choose functionality for
         right or left mouse buttons [More options are available when 
         editting a real graph (see Edit Graphs).]  Enter
         into the Size boxes, the default width and height to use
         when creating a new graph.  When a graph is created by another
         program (such as fv), it determines the size of the graph, so
         these options are usually overridden.  The Scaling buttons
         activate logarithmic graphs.  The first row of linear and
         log buttons cause each axis to be drawn in either linear
         or logarithmic format.  This does not affect the data, just how
         the graph coordinates are interpretted and labeled.  You can
         control the logarithmic conversion of individual curve data from
         the Points and Lines panes.
    
         The mouse control button can be clicked to switch the functionality
         of mouse buttons. Default will be left mouse button to control image
         zoom factor, and right mouse button to control brightness/contrast.
  • Fonts
    
         This pane controls the appearance of text in the graph.  One can
         independently set the font, size, style, and color of the Title,
         Axis Labels, Tick Labels, and default Text Labels.
         The Text Label value is used only for the initial text label.  All
         subsequent labels inherit their values from the previous label.
  • Ticks
    
         This pane controls the appearance of the tick marks and
         associated grid lines.  Use the slidebars to indicate
         approximately how many tick marks should be drawn (and labeled)
         on each axis of the graph.  At the far left, no tickmarks will be
         drawn on each axis.  At the far right, about 30 may be drawn.
         The X Ticks and Y Ticks options control whether the
         X and Y tickmarks are drawn inside or outside the graph's box and
         whether they are labeled on the left and bottom axes.  The
         Tick Labels option selects between Decimal and Base 60
         (degrees minutes seconds) numerical formats.  Base 60 is only used
         when a graph contains WCS information.  If the Grid Lines
         checkbox is selected, lines will drawn on the graph, tracing the
         path of each tick mark coordinate.  One can control the
         Color and line Style (solid, dashed, etc) of these
         lines.
  • Points
    
         The checkbox at the top of this item indicates whether the
         individual points of the curve should be drawn.  The points can
         be drawn as any of the 7 listed shapes.  The size
         of the points (except Dot which is always 1 point) can either be
         fixed at a constant size indicated by the slidebar, or
         drawn with widths/heights indicating the X and Y error
         bars.  If there are X/Y error bars but the points are drawn
         in a fixed style, the error bars will be indicated by
         horizontal/vertical lines centered on the point.  Points can be
         Filled or just drawn in outline.  Finally, select the
         desired color from the displayed colorbar.  This can be a
         different color than selected in the Lines pane.
    
         At the bottom are a pair of LogX/logY checkbuttons labeled
         Transform (This is the same option as in the Lines pane).
         Checking these will cause curves to have the logarithm of their
         data plotted instead of the data itself.  This does not
         automatically result in logarithmic axes, which are turned on
         from the Graph pane.  Unless you will always want your data to be
         converted to a certain logarithm format, these options should be
         left unset.
  • Lines
    
         The checkbox at the top of this pane indicates whether data
         points will be connected with a continuous line.  The line can be
         of several patterned styles or widths.  The points
         can also be connected directly (Normal) or in a
         stair-step pattern (Histogram).  In the latter mode, the
         Fill Boxes option draws the histogram as a series of solid
         boxes instead of an outline.  Finally, select the desired color
         from the displayed colorbar.  This can be a different color than
         selected in the Points pane.
    
         At the bottom are a pair of LogX/logY checkbuttons labeled
         Transform (This is the same option as in the Points pane).
         Checking these will cause curves to have the logarithm of their
         data plotted instead of the data itself.  This does not
         automatically result in logarithmic axes, which are turned on
         from the Graph pane.  Unless you will always want your data to be
         converted to a certain logarithm format, these options should be
         left unset.
  • Image
    
         This pane controls the appearance of images.  Most of the pane
         consists of a bunch of different colormaps.  They are grouped in
         the same sequence as listed in the Color menu: smooth, continuous
         colormaps, followed by ramps, then the step functions.  The
         Invert option will reverse the order of the colormap when
         turned on.  The Scaling option controls how the colormap
         is applied to the image.  For Linear scaling, each
         colormap level corresponds to a constant intensity range in the
         image.  Square-Root scaling changes the mapping such that
         the intensity range covered by each color level increases as the
         square-root function, producing higher contrast at lower
         intesities.  Logarithmic scaling uses the logarithmic
         function for colormapping, giving even more contrast at low
         intensities than sqrt.  Histo Equalize scaling computes
         a histogram of the image and tries to distribute colors equally
         over the number of pixels.

Clicking the Reset button will revert the options to their values when the dialog box was initially opened, undoing any modifications. Clicking the Save button will make the current settings the defaults for new graphs and save them in your .powrc file. The Get Current button grabs any available options from the current graph. Its current image (if present) will be used for the default image options and its first curve (if present) for the default curve options. Exitting will also make the new settings the current defaults, but won't save them.


Pages maintained by Bryan Irby
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Last modified: Tuesday, 01-Aug-2006 14:44:00 EDT