xgraph - Draw a graph on an X11 Display

xgraph [ options ] [[-geometry |=]WxH+X+Y ] [ -display host:display.screen ] [ file ... ]

The xgraph program draws a graph on an X display given data read from either data files or from standard input if no files are specified. It can display up to 64 independent data sets using different colors and/or line styles for each set. It annotates the graph with a title, axis labels, grid lines or tick marks, grid labels, and a legend. There are options to control the appearance of most components of the graph.

The input format is similar to graph(1) but differs slightly. The data consists of a number of data sets. Data sets are separated by a blank line. A new data set is also assumed at the start of each input file. A data set consists of an ordered list of points of the form "{directive} X Y". The directive is either "draw" or "move" and can be omitted. If the directive is "draw", a line will be drawn between the previous point and the current point (if a line graph is chosen). Specifying a "move" directive tells xgraph not to draw a line between the points. If the directive is omitted, "draw" is assumed for all points in a data set except the first point where "move" is assumed. The "move" directive is used most often to allow discontinuous data in a data set. The name of a data set can be specified by enclosing the name in double quotes on a line by itself in the body of the data set. The trailing double quote is optional. Overall graphing options for the graph can be specified in data files by writing lines of the form "<option>: <value>". The option names are the same as those used for specifying X resources (see below). The option and value must be separated by at bleast one space. An example input file with three data sets is shown below. Note that set three is not named, set two has discontinuous data, and the title of the graph is specified near the top of the file.

TitleText: Sample Data
0.5 7.8
1.0 6.2
"set one
1.5 8.9

"set two" -3.4 1.4e-3 -2.0 1.9e-2 move -1.0 2.0e-2 -0.65 2.2e-4

2.2 12.8 2.4 -3.3 2.6 -32.2 2.8 -10.3

After xgraph has read the data, it will create a new window to graphically display the data. The interface used to specify the size and location of this window depends on the window manager currently in use. Refer to the reference manual of the window manager for details.

Once the window has been opened, all of the data sets will be displayed graphically (subject to the options explained below) with a legend in the upper right corner of the screen. To zoom in on a portion of the graph, depress a mouse button in the window and sweep out a region. xgraph will then open a new window looking at just that portion of the graph. xgraph also presents three control buttons in the upper left corner of each window: Close, Hardcopy, and About. Windows are closed by depressing a mouse button while the mouse cursor is inside the Close button. Typing EOF (control-D) in a window also closes that window. Depressing a mouse button while the mouse cursor is in the Hardcopy button causes a dialog to appear asking about hardcopy (printout) options. These options are described below:

Output Device

Specifies the type of the output device (e.g. "HPGL", "Postscript", etc). An output device is chosen by depressing the mouse inside its name. The default values of other fields will change when you select a different output device.

Disposition

Specifies whether the output should go directly to a device or to a file. Again, the default values of other fields will change when you select a different disposition.

File or Device Name

If the disposition is "To Device", this field specifies the device name. A device name is the same as the name given for the -P command of lpr(1). If the disposition is "To File", this field specifies the name of the output file.

Maximum Dimension

This specifies the maximum size of the plot on the hardcopy device in centimeters. xgraph takes in account the aspect ratio of the plot on the screen and will scale the plot so that the longer side of the plot is no more than the value of this parameter. If the device supports it, the plot may also be rotated on the page based on the value of the maximum dimension.

Include in Document

If selected, this option causes xgraph to produce harcopy output that is suitable for inclusion in other larger documents. As an example, when this option is selected the Postscript output produced by xgraph will have a bounding box suitable for use with psfig.

Title Font Family

This field specifies the name of a font to use when drawing the graph title. Suitable defaults are initially chosen for any given hardcopy device. The value of this field is hardware specific -- refer to the device reference manual for details.

Title Font Size

This field specifies the desired size of the title fonts in points (1/72 of an inch). If the device supports scalable fonts, the font will be scaled to this size.

Axis Font Family and Axis Font Size

These fields are like Title Font Family and Title Font Size except they specify values for the font xgraph uses to draw axis labels, and legend descriptions.

Control Buttons

After specifing the parameters for the plot, the "Ok" button causes xgraph to produce a hardcopy. Pressing the "Cancel" button will abort the hardcopy operation. Depressing the About button causes Xgraph to display a window containing the version of the program and an electronic mailing address for the author for comments and suggestions.

xgraph accepts a large number of options most of which can be specified either on the command line, in the user's .Xdefaults or .Xresources file, or in the data files themselves. A list of these options is given below. The command line option is specified first with its X default or data file name (if any) in parenthesis afterward. The format of the option in the X defaults file is "program.option: value" where program is the program name (xgraph) and the option name is the one specified below. Option specifications in the data file are similar to the X defaults file specification except the program name is omitted.

-geometry WxH+X+Y or =WxH+X+Y (Geometry)

Specifies the initial size and location of the xgraph window.

-<digit> <name>

These options specify the data set name for the corresponding data set. The digit should be in the range '0' to '63'. This name will be used in the legend.

-bar (BarGraph)

Specifies that vertical bars should be drawn from the data points to a base point which can be specified with -brb. Usually, the -nl flag is used with this option. The point itself is located at the center of the bar.

-bof (BarGraph)

Offset the bars for additional datasets by the specified amount.

-device <name>

Set the output device for xgraph. The default is 'X'; other valid devices are 'ps', 'hpgl', 'idraw' and tgif.

-o <filename> -O <filename>

Set the output file name for postscript, hpgl and idraw devices. Files created with -O can be used other documents, and files generated with -o can be printed directly.

-P<printername>

Set the printer name for postscript or hpgl devices. This and the -o or -O option are mutually exclusive.

-stk

Stack elements coming from different datasets, instead of plotting them from the same baseline. Datasets must match exactly.

-fitx

Translate and scale the x data from all datasets to fit [0..1]. -fity Translate and scale the y data from all datasets to fit [0..1].

-scale <factor>

Output scale factor for postscript, hpgl and idraw devices. The default is 1.0, and 0.5 will generate a 50% reduced plot.

-fmtx <printf-format> -fmty <printf-format>

Use the format specified to generate the legents for the x or y axis.

-bb (BoundBox)

Draw a bounding box around the data region. This is very useful if you prefer to see tick marks rather than grid lines (see -tk).

-bd <color> (Border)

This specifies the border color of the xgraph window.

-bg <color> (Background)

Background color of the xgraph window.

-brb <base> (BarBase)

This specifies the base for a bar graph. By default, the base is zero.

-brw <width> (BarWidth)

This specifies the width of bars in a bar graph. The amount is specified in the user's units. By default, a bar one pixel wide is drawn.

-bw <size> (BorderSize)

Border width (in pixels) of the xgraph window.

-db (Debug)

Causes xgraph to run in synchronous mode and prints out the values of all known defaults.

-fg <color> (Foreground)

Foreground color. This color is used to draw all text and the normal grid lines in the window.

-gw (GridSize)

Width, in pixels, of normal grid lines.

-gs (GridStyle)

Line style pattern of normal grid lines.

-lf <fontname> (LabelFont)

Label font. All axis labels and grid labels are drawn using this font. A font name may be specified exactly (e.g. "9x15" or "-*-courier-bold-r-normal-*-140-*") or in an abbreviated form: <family>-<size>. The family is the family name (like helvetica) and the size is the font size in points (like 12). The default for this parameter is "helvetica-12".

-lnx (LogX)

Specifies a logarithmic X axis. Grid labels represent powers of ten.

-lny (LogY)

Specifies a logarithmic Y axis. Grid labels represent powers of ten.

-lw width (LineWidth)

Specifies the width of the data lines in pixels. The default is zero.

-lx <xl,xh> (XLowLimit, XHighLimit)

This option limits the range of the X axis to the specified interval. This (along with -ly) can be used to "zoom in" on a particularly interesting portion of a larger graph.

-ly <yl,yh> (YLowLimit, YHighLimit)

This option limits the range of the Y axis to the specified interval.

-m (Markers)

Mark each data point with a distinctive marker. There are eight distinctive markers used by xgraph. These markers are assigned uniquely to each different line style on black and white machines and varies with each color on color machines.

-M (StyleMarkers)

Similar to -m but markers are assigned uniquely to each eight consecutive data sets (this corresponds to each different line style on color machines).

-nl (NoLines)

Turn off drawing lines. When used with -m, -M, -p, or -P this can be used to produce scatter plots. When used with -bar, it can be used to produce standard bar graphs.

-ng (NoLegend)

Turn off drawing Legends. Can be used to increase the drawing area.

-p (PixelMarkers)

Marks each data point with a small marker (pixel sized). This is usually used with the -nl option for scatter plots.

-P (LargePixels)

Similar to -p but marks each pixel with a large dot.

-rv (ReverseVideo)

Reverse video. On black and white displays, this will invert the foreground and background colors. The behaviour on color displays is undefined.

-t <string> (TitleText)

Title of the plot. This string is centered at the top of the graph.

-tf <fontname> (TitleFont)

Title font. This is the name of the font to use for the graph title. A font name may be specified exactly (e.g. "9x15" or "-*-courier-bold-r-normal-*-140-*") or in an abbreviated form: <family>-<size>. The family is the family name (like helvetica) and the size is the font size in points (like 12). The default for this parameter is "helvetica-18".

-tk (Ticks)

This option causes xgraph to draw tick marks rather than full grid lines. The -bb option is also useful when viewing graphs with tick marks only.

-tkax (Tick Axis)

When tick marks are enabled, plot the axes.

-x <unitname> (XUnitText)

This is the unit name for the X axis. Its default is "X".

-y <unitname> (YUnitText)

This is the unit name for the Y axis. Its default is "Y".

-zg <color> (ZeroColor)

This is the color used to draw the zero grid line.

-zw <width> (ZeroWidth)

This is the width of the zero grid line in pixels.

Some options can only be specified in the X defaults file or in the data files. These options are described below:

<digit>.Color

Specifies the color for a data set. Eight independent colors can be specified. Thus, the digit should be between '0' and '7'. If there are more than eight data sets, the colors will repeat but with a new line style (see below).

<digit>.Style

Specifies the line style for a data set. A string of ones and zeros specifies the pattern used for the line style. Eight independent line styles can be specified. Thus, the digit should be between '0' and '7'. If there are more than eight data sets, these styles will be reused. On color workstations, one line style is used for each of eight colors. Thus, 64 unique data sets can be displayed.

Device

The default output form presented in the hardcopy dialog (i.e. "Postscript", "HPGL", etc).

Disposition

The default setting of whether output goes directly to a device or to a file. This must be one of the strings "To File" or "To Device".

FileOrDev

The default file name or device string in the hardcopy dialog.

ZeroWidth

Width, in pixels, of the zero grid line.

ZeroStyle

Line style pattern of the zero grid line.

David Harrison University of California

- Zooming in on bar graphs doesn't work right.

- There is no way to produce hardcopy without running xgraph interactively.