|
Chapters: 1: Introduction 2: Simple example 3: Invocation 4: Finer Control 5: X-Y Plots 6: Contour Plots 7: Image Plots 8: Examples 9: Gri Commands 10: Programming 11: Environment 12: Emacs Mode 13: History 14: Installation 15: Gri Bugs 16: Test Suite 17: Gri in Press 18: Acknowledgments 19: License Indices: Concepts Commands Variables |
9.3.41: The `
Set various flags and parameters which Gri will use in later commands.
|
set axes style .style. \
| {offset [.dist_cm.]} \
| rectangular|none|default
|
Tell Gri how you want the axes to look, when they are drawn later.
set axes style 0'
Set axes to be rectangular, with an x-y axis frame labelled at the left
and bottom and tic marks on all axes.
set axes style 1'
As style `0', but only put tics on the lower and left axes.
set axes style 2'
As style `0' but without labels or tics on any axis,
i.e. just an axis frame.
set axes style offset [.dist_cm.]'
Set axes so that the actual x and y axes will be drawn with a space
separating them from the data area. The space, if not set by the
`.distance_cm.' option, will be equal to the current tic size (see
`set tic size'). This command can be used together with any other
`set axes style' command. It applies to both the `draw axes'
command and with any `draw x|y axis' command in which the axis
location is not explicitly given.
set axes style rectangular'
Set axes to be rectangular, with an x-y axes frame labelled at the left
and bottom.
set axes style none'
Tell gri not to bother drawing axes before drawing curves, etc.
set axes style default'
Same as `set axes style 0', and with `offset' turned off.
set arrow size'
`set arrow size .size. \
| {as .num. percent of length} \
| default'
|
Set the arrowsize (which is stored in the builtin variable
`..arrowsize..').
set arrow size .size.'
Set the arrow size (ie, half-width of the arrowhead) to `.size.'
centimetres.
set arrow size as .num. percent of length'
Set the arrow size to be the indicated percentage of arrow length, as in
"HWP" in the singles ads. (As a flag to this, `..arrowsize..' is
set to the negative of the fractional size measured in percent.)
set arrow size default'
Set the arrow size to the default of 0.2 cm.
set arrow type'
set arrow type .which. |
Set type of arrow, according to the value of `.which.', rounded to
the nearest integer. A rounded `.which.' value of 0 yields the
default arrows, drawn with three line strokes. Value 1 yields outlined
arrows, sometimes used on definition sketches. Value 2 yields filled,
swept-back arrow heads.
This command uses the ``line join'' parameters that are presently active (see Set Line Join). So, by default, the arrow ends are rounded (because the default line-join parameter is 1). To get pointy ends, first set the line join parameter to 0.
set beep'
`set beep on|off' |
The command `set beep on' makes gri beep on errors and
`query'. `set beep off' (the default) turns this beeping off.
set bounding box'
`set bounding box .xleft. .ybottom. .xright. .ytop. [pt|cm]' |
Set the PostScript bounding box for the graph to the indicated values. The bounding box is used by some programs to determine the region of the page on which marks have been made. For example, LaTeX uses the bounding box to decide how to position figures in documents.
Normally, the bounding box is computed automatically unless the
`-no_bounding_box' commandline option has been specified;
(see Invoking Gri). But if `set bounding box' is
done, the automatically computed value is ignored and the given box is
used instead. Use this if Gri makes mistakes in its automatic selection
of bounding box.
The coordinates of the bounding box may be specified in (1) user
coordinates, as defined at the moment the command is executed, or
(2) in points on the page, measured from an origin at the lower-left
(72 point per inch), or (3) in centimeters on the page. Which coordinate
system is used depends on the last keyword -- use `pt' for points,
`cm' for centimeters, and nothing at all for user-units.
The most common use is in points, since that is how many other application packages, e.g. LaTeX and dvips, specify the bounding box.
If the box is specified in the user units, the user units in effect
at the moment of executing the `set bounding box' command
are used. This must be born in mind if the coordinate system is
changing during the execution of the program, e.g. if margins are
changing or the x and y axes are changing. For this reason it often
makes sense to put this command at the end of the commandfile.
set clip'
`set clip [postscript] \
{on [.xleft. .xright. .ybottom. .ytop.]} \
{to curve} \
| off'
|
Control clipping of following drawing commands. Note that the
commands have two styles, one of which includes the keyword
`postscript'. PostScript clipping does a cleaner job, but it
results in larger file sizes. Important if you are using
`postscript' clipping, then you be sure to turn it off
using `set clip postscript off', instead of `set clip off';
otherwise Gri will get mixed up.
set clip on'
Don't plot data outside axes.
set clip postscript on'
As above, but Postscript clipping.
set clip on .xleft. .xright. .ybottom. .ytop.'
Don't plot data outside indicated box.
set clip postscript on .xleft. .xright. .ybottom. .ytop.'
As above, but Postscript clipping.
set clip off'
Plot all data, whether inside the axes or not.
set clip postscript off'
As above, but Postscript clipping.
set clip to curve' set clip to the curve, as
would be drawn by a `draw curve filled' command, i.e. to the
polygon constructed by running along the xy points, in order, followed
by a final segment from the last point back to the first point. This is a
"postscript" clip, as explained in the next item.
set clip postscript to curve'
As above, but Postscript clipping.
draw axes set clip postscript on 10 20 0 1 draw curve set clip postscript off |
set clip postscript off'
Turn PostScript clipping off.
See also `set input data window'.
set color'
`set color \name | \
{rgb .red. .green. .blue.} | \
{hsb .hue. .saturation. .brightness.}'
|
Set the color of the ``pen'' used for drawing lines and text. Normally
lines and text are drawn in the same color, but the text color can be
specified independently if desired (see Set Font Color). This might be
useful to get contour lines of one color and labels of another. The
spelling `colour' is also accepted.
In the `set color \name' style, set the drawing color to the
indicated name, either from the builtin list (`white',
`LightGray', `darkslategray', `black', `red',
`brown', `tan', `orange', `yellow', `green',
`ForestGreen', `cyan', `blue', `skyblue',
`magenta'), or from a list created by `read colornames'. In
the latter case, if the colorname has more than one word in it, use
quotes, e.g. `set color "ghost white"'.
In the `set color rgb ...' style, set the individual color
components as indicated. The numbers `.red.', `.green.' and
`.blue.' range from 0 (for no contribution of that color component
to the final color) to 1 (for maximal contribution). Values less than 0
are clipped to 0; values greater than 1 are clipped to 1. EXAMPLES:
set color rgb 0 0 0 # black set color rgb 1 1 1 # white set color rgb 1 0 0 # bright red set color rgb 0.5 0 0 # dark red (only 50 percent) set color rgb 0 1 0 # pure green set color rgb 1 1 0 # yellow: red + green |
In the `set color hsb ...' style, set the individual color
components as indicated. The numbers `.hue.', `.saturation.'
and `.brightness.' range from 0 to 1. The color, represented by
.hue., ranges from 0 for pure red, through 1/3 for pure green, and 2/3
for pure blue, and back to 1 again for pure red. The purity of the
color, represented by .saturation., ranges from 0 (none of the hue is
visible) to 1 (the maximal amount is present). The brightness of the
color, represented by `.brightness.', ranges from 0 (black) to 1
(maximal brigntness). Values less than 0 are clipped to 0; values
greater than 1 are clipped to 1. EXAMPLES:
set color hsb 0 1 1 # pure, bright red set color hsb 0 1 0.5 # half black, half red set color hsb .333 1 1 # pure, bright green |
set colorname'
`set colorname \name {rgb .red. .green. .blue.} \
| {hsb .hue. .saturation. .brightness.}'
|
Create a colorname with the indicated color. The color components range from 0 to 1, and will be clipped to these values if they are outside this range. EXAMPLE (borrowing a color from `/usr/lib/X11/rgb.txt'):
set colorname peachpuff rgb 1 {rpn 218 255 / } {rpn 185 255 / }
draw box filled 2 2 3 3 cm
|
This command is akin to `read colornames' (see Read Colornames),
except that the latter uses an X11 database, so the color constituents
range from 0 to 255, whereas for `set colorname' they range from 0
to 1.
set contour format'
`set contour format \style|default' |
Normally, Gri draws the numeric labels of contours using a format code
called `%g' in the "C" language. You may specify any other "long"
format using this command. For example, `set contour format %.1f'
tells Gri to use one decimal place in the numbers, and also to prefer
the "float" notation to the exponential notation. `set contour format default' resets to the default `%f' format. You may use
quotes around the format if you need to, to make the item be a single
word (e.g. `set contour format "%.1f m/s"').
set contour label for'
`set contour label for lines exceeding .x. cm' |
Make it so contour lines shorter than `.x.' centimeters will not be
labelled.
set contour label position'
`set contour label position \
{.start_cm. .between_cm.} \
| centered \
| default'
|
By default, contour labels are drawn at the location 1 cm into the
contour curve, measured from the startpoint of the contour (e.g., for
contours crossing the axes frames, the label will be 1 cm from the
frame), and then at a uniform distance along the contour. By default,
this uniform distance is the average dimension of the plotting area
inside the axes. If `.start_cm.' and `.between_cm.' are
specified, the first label is drawn at a distance `.start_cm.' from
the start of the contour, and thereafter at a separation of
`.between_cm.'.
If the `centered' option is used, then the contour labels are
centered along the length of the line.
set contour labels'
set contour labels rotated \ | horizontal \ | whiteunder \ | nowhiteunder |
The first two options control whether contour labels are rotated to line up with the contour lines, or whether they are horizontal (the default).
The second two options control whether the region under contour labels
is whited out before drawing the label. The default is
`whiteunder', which has the visual effect of the label having been
drawn on a piece of paper and then pasted on. This can look jarring
when the material under the contour is an image. When
`nowhiteunder' is specified, the contour line is broken to make
space for the text, but no whiting out is done.
set dash'
`set dash [.n.|{.dash_cm. .blank_cm. ...}|off]'
|
Control dash-style for following `draw curve' and `draw line'
commands.
set dash'
Set to dashed line (0.4cm dashes, 0.1cm blanks).
set dash .n.'
Set to indicated pre-defined dashed line, according to table:
.n. dash/cm blank/cm 0 - - ... (Solid line) 1 0.2 0.1 2 0.4 0.1 3 0.6 0.1 4 0.8 0.1 5 1.0 0.1 10 w w 11 w 2w 12 w 3w 13 w 4w 14 w 5w 15 w 6w |
Where `w' is written, it indicates the current linewidth. Thus,
types 10 through 15 give square-dotted lines.
set dash .dash_cm. .blank_cm. .dash_cm. .blank_cm. ...'
Set to indicated dashed line. The series of lengths `.dash_cm.'
and `.blank_cm.' give the lengths of dash and blank portions
(measured in centimeters). Any number of dash/blank lengths may be
given. For example, `set dash 0.5 0.1 0.1 0.1' looks good.
set dash off'
Turn dashing off, setting to a solid line.
set environment'
`set environment' |
Set environment (graylevel, axis length, etc) so that following plotting
commands will make use of anything set by either a `set' command or
by direct manipulation of builtin variables like `..xsize..', etc.
NOTE: this should only be done by developers.
set error'
`set error action to core dump' |
Make Gri dump core when any error is found, to facilitate debugging.
set flag'
`set flag \name [off]' |
Set the indicated flag to YES. The name of the flag is contained in a
single word, e.g. `set flag dan_28sep_test'. The action of the
flags may change with time and is undocumented. This command is
provided to enable selected users (e.g., the developer himself) to use
test features of Gri before they are frozen into a fixed syntax and
action. The keyword `off' turns the indicated flag off. NOTE:
this should only be done by developers.
FLAG DATE ACTION |
set font color'
set font color \name | \
{rgb .red. .green. .blue.} | \
{hsb .hue. .saturation. .brightness.}
|
The syntax is the same as `set color', except that this applies to
text only. By default, text is drawn in the same color as lines, so
text color is changed as line color is changed (e.g. by using the
`set color' or `set graylevel' commands)). However, once
`set font color' is used in a Gri program, the font thereafter
maintains a separate color from the lines.
set font encoding'
set font encoding PostscriptStandard | isolatin1 |
Permits one to control the so-called ``font encoding'' used in text. The default font encoding is ISO-Latin-1, which is best for English and other European languages. To learn how to enter accents in a text editor, and for a brief overview of font encodings, (see Non-English Text).
If the so-called ``Postscript Standard'' font encoding is required, this command permits changing the encoding.
Note: few users will ever need this command. If you don't even know what ``font encoding'' is about, ignore this command!
set font size'
`set font size {.size. [cm]}|default'
|
Set the size of the font for drawing of text.
set font size .size.'
Set font size to `.size.' points. (A point is 1/72 of an inch,
or 1/28 of a centimetre.)
set font size .size. cm'
Set font size to `.size.' centimetres.
set font size default'
Set font size to default = 12 pts.
If your figure is to be reproduced by a journal, you should check with them about the range of font size they need. This will, of course, depend on whether your figure is reduced or enlarged during reproduction. For example, American Geophysical Union (publishers of J. Geophysical Res.) recommends that one use fonts no smaller than 8 points. They also recommend that the range in fontsize in a given figure not exceed 2.
set font to'
`set font to \fontname' |
Set font to named style. Note that the backslash is not to be
written, but here merely means that this word has several alternatives.
For example, one might say `set font to Courier'. The allowed
fontnames are:
`Courier', a typewriter font (and the only monospaced font in Gri);
`Helvetica' (the default), a sans-serif font commonly used in drafting scientific graphs;
`HelveticaBold', a bold version of Helvetica;
`Times' (also called `TimesRoman'), a font used in most newspapers;
`TimesBold', a bold version of Times;
`Palatino' (also called `PalatinoRoman'), similar to Times;
`Symbol', included for completeness, is a
mathematical font in which "a" becomes $\alpha$ of the math mode, etc.
For reference on these fonts see any book on PostScript. The default
font is `Helvetica'.
set graylevel'
`set graylevel .brightness.|white|black' |
Set graylevel for lines to indicated numerical value between 0=black and 1=white, or to the named color.
Note: if your diagram is to be reproduced by a journal, it is unlikely that the reproduction will be able to distinguish between any two graylevels which differ by less than 0.2. Also, graylevels less than 0.2 may appear as pure black, while those of 0.8 or more may appear as pure white. These guidelines are as specified by American Geophysical Union (publishers of J. Geophysical Res.), as of 1998.
set grid missing'
`set grid missing \
{above|below .intercept. .slope} \
| {inside curve}'
|
The style
`set grid missing above|below .intercept. .slope' |
sets grid to missing value for all points above/below the line defined by
y = .intercept. + .slope. * x
The style
`set grid missing inside curve' |
sets the grid to the missing value throughout an area described
by the curve last read in with `read columns'. This is
useful for e.g. excluding land areas while contouring ocean
properties. The curve may contain several "islands," each
tracing (clockwise) a region inside of which the grid is to
considered missing. If the first point in an island doesn't
match the last, then an imaginary line is assumed which connects
them. Multiple islands may be separated by missing-value codes.
See also `Set Z Missing'.
set ignore initial newline'
`set ignore initial newline [off]' |
Make Gri ignore a newline if it occurs as the first character of the next data file. This is used for files made by FORTRAN programs on VAX/VMS computers.
set ignore error eof'
`set ignore error eof' |
Stop Gri from considering that to encounter an end of file in future
`read' commands consitutes an error; Gri will simply warn about
future EOFs.
set image colorscale'
set image colorscale hsb .h. .s. .b. .im_value. \
hsb .h. .s. .b. .im_value. [increment .im_value.]
set image colorscale rgb .r. .g. .b. .im_value. \
rgb .r. .g. .b. .im_value. [increment .im_value.]
set image colorscale \
\name .im_value. \
\name .im_value. \
[increment .im_value.]
|
Set colorscale mapping for image, using HSB (hue, saturation,
brightness) specification, RGB (red, green, blue) color specification,
or named colors. The image range must previously have been set by
`set image range', so that the `.im_value.' values will have
meaning. Two pairs of (color, image-value) are given, and possibly an
increment. Normally the colors are smoothly blended between the
endpoints, but if an increment is supplied, the colors are quantized.
The HSB method allows creation of spectral palettes, while the other two
methods create simple blending between the two endpoints.
EG: To get a spectrum ranging between pure red (H=0) for image value of -10.0, and pure blue (H=2/3) for image value of 10.0, do this:
set image colorscale hsb 0 1 1 -10 hsb .666 1 1 10 |
EG: To get a scale running from pure red (at image-value 10.0) into pure
blue (at image-value 25.1), but with the colors blending intuitively in
between (i.e., blending as paint might), use `rgb' color
specification, as follows:
set image colorscale rgb 1 0 0 10 rgb 0 0 1 25.1 |
EG: To get a quantized blend between the X11 colors `skyblue' at
image value of 0 and `tan' at image value of 20, and with steps at
image values incrementing by 5, do this:
set image colorscale skyblue 0 tan 20 increment 5 |
Note that the traversal is through RGB space, so it is
intuitive, not spectral. See `set color' for a list of X11 colors
known to Gri.
See also `read image colorscale' (see Read Image Colorscale).
set image grayscale'
`set image grayscale using histogram \ [black .bl. white .wh.]' |
Set up a grayscale mapping for images. The image range must have
previously have been set by `set image range'.
`set image grayscale using histogram [black .bl. white .wh.]' |
Create a grayscale mapping using linearized cumulative histogram enhancement. The image must already exist.
This creates maximal contrast in each range of graylevels, and is useful for tracing subtle features between different images (for example, it makes it easier to trace fronts between successive satellite images). The entire histogram is expanded, from the smallest value in the image to the largest.
With no options specified, the histogram is done from 0 in the image to 255 in the image. If the black/white options are specified, the histogram is done between these values.
`set image grayscale \ [black .bl. white .wh. [increment .inc.]]' |
With no optional parameters, create a grayscale mapping for the current
image, scaling it from black for the mininum value in the image to white
for the maximum value. The image range must have previously have been
set by `set image range'.
The optional parameters `.wh.' and `.bl.' specify the values
to be drawn in white and black in the image, with smooth linear blending
in between.
Normally the blending from white to black is smooth (linear), but if the
additional optional parameter `.inc.' is specified, the blending is
quantized, jumping to darker values at (`.wh.' + `.inc.'),
(`.wh.' + 2* `.inc.'), etc. (The sign of `.inc.' will be
altered, if necessary, to ensure that (`.wh.' + `.inc.') is
between `.wh.' and `.inc.'.) The colour switches to pure
white at the value `.wh.', and remains pure white everywhere on the
"white" side of this value. Similarly, the transition to pure black
occurs at the value `.bl.'. In other words, neither pure white nor
pure black is present inside the interval from `.wh.' to
`.bl.'. Therefore, when using the `draw image palette'
command, you might want to extend the range by one increment so as to
get an example of both pure white and pure black.
.w. = 0
.b. = 1
.i. = 0.2
set image grayscale white .w. black .b. increment .i.
draw image palette left \
{rpn .w. .i. -} \
right {rpn .b. .i. +} \
increment .i.
|
set image missing value color'
`set image missing value color to white|black|\
{graylevel .brightness.}|{rgb .r. .g. .b.}`
|
Set the color of ``missing'' pixels (white by default). The image range
must have previously have been set by `set image range'. Pixels
with missing values can result from creating images from grids which
have missing values; see the `convert grid to image' command. The
`.brightness.' parameter in the `graylevel' style ranges from
0 for black to 1 for white. The `rgb' parameters allow setting to
full color.
set image range'
`set image range {.min_value. .max_value.}|{from grid}'
|
In the first style, specify the minimum and maximum image values. In the second, set the image range from the range of the grid data.
In either case, Gri needs to know the image range because it stores images in a
limited format capable of holding only 256 distinct values. Unlike some other
programs, Gri encourages (forces) the user to specify things in terms of
user-units, not image-units. This has the advantage of working regardless of
the number of bits per pixel. Thus, for example, `set image grayscale',
`set image colorscale', `draw image grayscale', etc, all use *user*
units.
When an image is created by `convert grid to image', values outside the
range spanned by `.0value.' and `.255value.' are clipped. (There is
no need, however, for `.0value.' to be less than `.255value.'.) This
clipping discards information, so make sure the range you give is larger than
the range of data in the grid.
EXAMPLE: consider a satellite image in which an internal value of 0 is meant to
correspond to 0 degrees Celsius, and an internal value of 255 corresponds to
25.5 degrees. (This is a common scale.) Then Gri command `set image range 0 25.5' would establish the required range. If this range were combined
with a linear grayscale mapping (see `set image grayscale'), the resultant
granularity in the internal representation of the user values would be
(25.5-0)/255 or 0.1 degrees Celsius; temperature variations from pixel to pixel
which were less than 0.1 degrees would be lost.
All other image commands *require* that the range has been set. Thus, all
these commands fail unless `set image range' has been done: `draw image', `draw image palette', `read image', `convert grid to image', `set image grayscale', and `set image colorscale'.
NOTE: If a range already exists when `set image range' is used, then the
settings are altered. Thoughtless usage can therefore lead to confusing
results. (The situation is like setting an axis scale, plotting a curve with
no axes, then altering the scale and plotting the new axes. It's legal but not
necessarily smart.)
set input data window'
`set input data window x|y {.min. .max.}|off'
|
Create a data window for following `read' statements.
set input data window x .min. .max.'
For future reading commands, ignore all data with x less than
`.min.' or x greater than `.max.' The data not in the interval
will not be read in at all. This will hold until
`set data window x off' is done, in which case all data will be read in.
set input data window x off'
Return to normal conditions, in which all data are read in.
set input data window y .min. .max.'
Analgous to command for x.
set input data window y off'
Analagous to command for x.
EXAMPLE: To set the input data window as the current x axis plus a border of 5 centimetres to left and right, do the following:
set input data window x \
{rpn ..xleft.. xusertocm 5 - xcmtouser} \
{rpn ..xright.. xusertocm 5 + xcmtouser}
|
See also `set clip'
set input data separator'
`set input data separator TAB|default' |
Set the separator between data items. The `default' method is to
assume that data items are separated by one or more spaces or tabs, and
also to ignore any spaces or tabs at the start of a data line.
In the `TAB' method the data are assumed to be separated by a
SINGLE tab character. (Multiple tabs will result in null values being
assigned to items -- almost certainly not what you want!) Also, initial
spaces and tabs on lines are NOT skipped.
Use the `TAB' method only after thinking carefully about the above,
since the assignment of null values is problematic.
set line cap'
`set line cap .type.' |
Set the type of ends (caps) of lines. Use `.type.' of value 0 for
square ends, cut off precisely at the end of line, or 1 for round ends
which overhang half the line width, or 2 for square ends which overhang
half the line width. The selected style is used for the ends of line
segments, as well as at corners. In PostScript parlance, therefore,
this command sets both the linecap and the linejoin parameters.
This command only applies to lines drawn with `draw curve',
`draw line' and `draw polygon'. Axes are always drawn with a
line cap of 0.
set line join'
`set line join .type.' |
Set the type of intersection of lines. Use `.type.' of value 0 for
mitered joins (pointy ends that may extend beyond the data points), a
value of 1 for rounded ends (the default), or a value of 2 for bevelled
(squared-off) ends. See the `setlinejoin' command in any text on
the PostScript language for more information.
This command only applies to lines drawn with `draw curve',
`draw line' and `draw polygon'. Axes are always drawn with a
line join of 0.
set line width'
`set line width \
[axis|symbol|all] \
.width_pt. \
| {rapidograph \name} \
| default'
|
Set the width of lines used to draw curves (default), axes, symbols, or all of the above. The width may be set to a value specified in points (conversion: 72 pt = 1 inch), to a named rapidograph width, or to the default value. The initial default values are: 0.709pt (or rapidograph 3x0) for curves; 0.369pt (or rapidograph 6x0) for axes; 0.369pt (or rapidograph 6x0) for symbols. (To learn more about standard pen widths, see the ISO 9175-1 documents.)
If your figure is to be reproduced by a journal, you should check with them about the range of line thicknesses they recommend. This will, of course, depend on whether your figure is reduced or enlarged during reproduction. For example, American Geophysical Union (publishers of J. Geophysical Res.) recommends that one use line thicknesses no less than 0.5 points and no more than 4 points.
The rapidograph settings match the standard set of widths used in
technical fountain pens. The table below gives width names along with
the width in points and centimetres, as given in the specifications
supplied with Rapidograph technical fountain pens. Names marked by the
symbol `*' are in sequence increasing by the factor root(2). Texts
on technical drawing often suggest using linewidths in the ratio of 2 or
root(2). On many printers, the variation in width from root(2) increase
is too subtle to see, so the factor-of-2 rule may be preferable. To get
sizes in a sequence doubling in width, pick from the list (`6x0',
`3x0', `1', `3.5' `7'). To get a sequence
increasing in width by root(2), pick from the list (`6x0',
`4x0', `3x0', `0', `1', `2.5', `3.5',
`6', `7'). The eye can distinguish curves with linewidths
differing by a factor of root(2) if the image is of high quality, but a
factor of 2 is usually better. Similarly, for overhead projections and
projected slides, one would do well to use linewidths differing by a
factor of 4.
This is the list of `rapidograph' linewidths:
Name pt cm
==== ===== =====
* 6x0 0.369 0.013
* 4x0 0.510 0.018
* 3x0 0.709 0.025
00 0.850 0.03
* 0 0.992 0.035
* 1 1.417 0.05
2 1.701 0.06
* 2.5 1.984 0.07
3 2.268 0.08
* 3.5 2.835 0.1
4 3.402 0.12
* 6 3.969 0.14
* 7 5.669 0.2
|
set missing value'
`set missing value .value.|none' |
If a numerical value is given, set the
missing-value code to that value, and also
store this value in the builtin variable
`..missingvalue..' and the builtin synonym `\.missingvalue..'
also. After this command, Gri will ignore any data that are within
0.1 percent of this value. (This feature is commonly used in geophysical
data.)
If `none' is given, turn off this feature.
The default is that the feature is turned off.
set page size'
`set page size letter|legal|folio|tabloid|A0|A1|A2|A3|A4|A5' |
Set the page dimension, as indicated below.
The effect is to possibly alter the PostScript "bounding box." If all the drawn material fits within the indicated page, then the bounding box is not altered. (In other words, Gri will still keep the bounding box tight on the drawn items.)
However, if any drawn item extends beyond the indicated size, it will be clipped to the boundary.
set page'
`set page portrait \
| landscape \
| {factor .mag.} \
| {translate .xcm. .ycm.}'
|
Control orientation or scaling of what is drawn on the paper.
set page portrait'
Print graph normally (default).
set page landscape'
Print graph sideways.
set page factor .mag.'
Scale everything to be drawn on the paper by the indicated magnification
factor. This must be called before any drawing commands.
set page translate .xcm. .ycm.'
Translate everything to be drawn on the paper by the indicated x/y
distances. This must be called before any drawing commands.
Note: The order of the factor/translate commands matters, so you may need to experiment. For example,
set page translate 2 1 set page factor 0.5 |
moves anything that would have been drawn at the lower-left corner of the paper onto the point 2cm from the left side and 1cm from the bottom side of the paper, and then applies the multiplication factor. Reversing the order gives quite different results. PostScript gurus should note that the following two commands are inserted into the PostScript file:
56.900000 28.450000 translate 0.500000 0.500000 scale |
set panel'
set panel .row. .col. |
Establish the geometry for the panel in the indicated row and column;
that is, select which defined panel to draw into. The
bottom row has `.row.' = 1, and the leftmost column has
`.col.' = 1. This must be used only after defining the panel
layout using `Panels .row. .col. .dx_cm. .dy_cm.'.
set panels'
set panels .rows. .cols. [.dx_cm. .dy_cm.] |
Set up for multipanel plots, with spacing `.dx_cm.' between the
columns and `.dy_cm.' between the rows. If the spacings are not
supplied, 2cm is used. The panels fill the rectangle which would
otherwise contain the single axis frame, as set by `set x size' and
`set x margin', etc.
The global variables `.panel_dx.', `.panel_dy.',
`.panel_xmargin.', `.panel_ymargin.', `.panel_xsize.',
and `.panel_ysize' are created, to be used by later calls to
`set panel'.
EXAMPLE
# Draw 2 panels across, 3 up the page. |
See also `set panel .row. .col.'
set path'
set path to "\path"|default for data|commands |
Set the directory path that `open' will search for data files, or
that `insert' will search for command files. This search will
not be done if the filename starts with a `/', `~', or
`.' character.
The path is formatted in a colon-separated manner, following the normal
Unix convention, and searching is from left to right. For example, the
path `".:/usr/lib/gri"' tells Gri to search for the file first in
the local directory (named `.'), and if it is not found there, to
look next in the directory named `/usr/lib/gri'.
The indicated path is stored in either `\.path_data.' or
`\.path_commands.', as appropriate. At startup time, each of these
paths is set to `"."', the current directory, and this value is
reset if the `default' keyword is provided to this command.
If you need to know where the file was eventually found, save the
`\.return_value.' just after the `open' command was executed.
For example, the following defines the synonym `\uk', which is the
full pathname of the file containing some sort of data about Great
Britain.
set path to "/atlases/world:/atlases/northern_hemisphere" for data open britain.dat # we don't know where file is ... \gb = "\.return_value." # ... until now! |
set postscript filename'
`set postscript filename "\name"' |
Set name of PostScript file, over-riding the present name.
set symbol size'
`set symbol size .diameter_cm.|default' |
Control the diameter of symbols drawn by `draw symbol' command.
set symbol size .diameter_cm.'
Make symbol size be `.diameter_cm.' centimeters in diameter.
set symbol size default'
Set to default diameter of 0.1 cm.
set tic size'
`set tic size .size.|default' |
Control size of tics on axes.
set tic size .size.'
Set tic size to `.size.' centimetres.
set tic size default'
Set tic size to default of 0.2 cm.
set tics in|out'
Make axis tics point inward or outward. The default is outward.
set trace'
`set trace [on|off]' |
Control printing of command lines as they are processed.
set trace'
Make Gri print command lines as they are processed.
set trace on'
Same as `set trace'.
set trace off'
Prevent printing command lines (default).
set transparency'
`set transparency .transparency.' |
Set the transparency of drawn items, 0 for opaque and 1 for invisibly faint. This command is provisional, as of summer 2004, and this part of the documentation needs to be fleshed out so users can build intuition on transparency. For example, a quick quiz: what color do you think comes from drawing red on top of yellow, or on top of blue?
set u scale'
`set u scale .cm_per_unit.|{as x}'
|
Set scale for x-component of arrows.
set u scale .cm_per_unit.'
Set scale for `u' component of arrows.
set u scale as x'
Set scale for u component of arrows to be the same as the x-scale.
Equivalent to
`set u scale as {rpn ..xsize.. ..xright.. ..xleft.. - /}'.
NOTE: this only works if the x-scale is LINEAR (see `set x type').
set v scale'
`set v scale .cm_per_unit.|{as y}'
|
Set scale for y-component of arrows.
set v scale .cm_per_unit.'
Set scale for `v' component of arrows.
set v scale as y'
Set scale for v component of arrows to be the same as the y-scale.
Equivalent to
`set v scale as {rpn ..ysize.. ..ytop.. ..ybottom.. - /}'.
NOTE: this only works if the y-scale is LINEAR (see `set y type').
set x axis'
`set x axis top' `set x axis bottom' `set x axis increasing' `set x axis decreasing' `set x axis unknown' `set x axis .left. .right. [.incBig. [.incSml.]] [labelling .labelling_value.]' `set x axis labels [add] .position_1. "label_1" [.position_2. "label_2" [...]]' `set x axis labels automatic' |
Control various things about the x axis.
set x axis top'
Make next x-axis to be drawn have labels above the axis.
set x axis bottom'
Make next x-axis to be drawn have labels below the axis.
set x axis increasing'
Make next x-axis to be drawn have numeric labels increasing to the
right. This applies only if autoscaling is done; otherwise, the
supplied values (`.left. .right. [.incBig. [.incSml.]]') are used.
set x axis decreasing'
Make next x-axis to be drawn have numeric labels decreasing to the
right. This applies only if autoscaling is done; otherwise, the
supplied values (`.left. .right. [.incBig. [.incSml.]]') are used.
set x axis unknown'
Make Gri forget any existing scale for the x axis, whether set by
another `set x axis' command or automatically, during reading of
data. This is essentially a synonym for `delete x scale'.
set x axis .left. .right.'
Make x-axis range from `.left.' to `.right.'
set x axis .left. .right. .incBig.'
Make x-axis range from `.left.' to `.right.', with labelled
increments at `.incBig.' Note: In the case of log axes, and
provided that `set x type log' has been called previously, the
`.incBig.' parameter has a different meaning: it is the interval,
in decades, between numbered labels; the default is 1.
set x axis .left. .right. .incBig. labelling .labelling_value.'
As above, but with the axis labels including the indicated value, and
incremented larger and smaller by `.incBig'. (This does not work
for logarithmic axes.)
set x axis .left .right. .incBig. .incSml.'
Make x-axis range from `.left.' to `.right.', with labelled
increments at `.incBig.', and small tics at `.incSml.' NOTE:
if the axis is logarithmic, the value of `.incSml.' takes on a
special meaning: if it is positive then small tics are put at values 2,
3, 4, etc. between the decades, but if `.incSml.' is negative then
no such small tics are used.
set x axis .left .right. .incBig. .incSml. labelling .labelling_value.'
As above, but with the axis labels including the indicated value, and
incremented larger and smaller by `.incBig'. (This does not work
for logarithmic axes.)
set x axis labels .position. "label" [.position. "label" [...]]'
Override the automatic labelling at axis tics, and instead put the
indicated labels at the indicated x values. For example, a
day-of-week axis can be created by the code:
set x axis 0 7 1
set x axis labels 0.5 "Mon" 1.5 "Tue" 2.5 "Wed" \
3.5 "Thu" 4.5 "Fri" 5.5 "Sat" \
6.5 "Sun"
|
The command replaces any existing labels, unless the `add' keyword is present, in which case the new label information is appended to any existing information.
set x axis labels automatic'
Return to automatically-generated axis labels, undoing the command of
the previous item.
set x format'
`set x format \format|default|off |
Set format for numbers on x axis. The format is specified in the manner
of the "C" programming language. The C formats (i.e., `%f',
`%e' and `%g') are permitted.
For example, `set x format %.1f' tells Gri to use 1 decimal place,
and to prefer the "float" notation to the exponential notation. The
form `set x format off' tells Gri not to write numbers on the axis.
To get spaces in your format, enclose the format string in
double-quotes, e.g., you might use `set x format "%.0f$\circ$ W"'
for a map, or `set x format "%f "' to make the numbers appear to
the left of their normal location.
The default format is `%lg'.
set x grid'
`set x grid .left. .right. .inc.|{/.cols.}'
|
Create x-grid for contour or image. If a grid already exists, an error
will be declared; the way to interpolate from an existing grid to a new
one is with the `interpolate x grid' command.
set x grid .left. .right. .inc.'
Create x-grid ranging from the value `.left.' at the left to
`.right.' at the right, stepping by an increment of `.inc.'.
set x grid .left. .right. /.cols.'
Create x-grid with `.cols.' points, ranging from the value
`.left.' at the left to `.right.' at the right.
set x margin'
`set x margin {[bigger|smaller] .size.}|default'
|
Control x margin, that is, the space between the left-hand side of the page and the left-hand side of the plotting area. (Note that axis labels are drawn inside the margin; the margin extends to the axis line, not to the labels.)
set x margin .size.'
Set left margin to `.size.' cm. It is permissible to have negative
margins, with the expected effect.
set x margin bigger .size.'
Increases left margin by `.size.' cm.
set x margin smaller .size.'
Decreases left margin by `.size.' cm.
set x margin default'
Set left margin to default = 6 cm.
set x name'
`set x name "\name"|default' |
Set name of x-axis to the indicated string. An empty string
(`set x name ""') causes the x axis to be unlabelled. The
`default' is `"x"'.
set x size'
`set x size .width_cm.|default' |
Set the width of the plotting area. This does not include axis labels, only the interior part of the plot.
set x size .width_cm.'
Set width of x-axis in centimeters.
set x size default'
Set width of x-axis to default = 10 cm.
set x type'
set x type linear|log|{map E|W|N|S}
|
Control transformation function mapping user units to centimetres on the page.
set x type linear'
Set to linear axis.
set x type log'
Set to log axis. To avoid clashes in the linear to log transform, this
command should precede the creation of an axis scale, either explicitly
through the `set x axis .left. .right. ...' command or implicitly
through the `read columns' command.
set x type map E|W|N|S'
Set to be a map. This means that whole numbers on the axis will have a
degree sign written after them (and then the letter `E', etc) and
that numbers which are multiples of 1/60 will be written in
degree-minute format, and that similarly numbers which are divisible by
1/3600 will be in degree-minute-second format. If none of these things
apply, the axis labels will be written in decimal degrees. Note that
this command overrides any format set by `set x format'.
BUG: this only has an effect if the axis is not already of type
`log'.
set y axis'
`set y axis left' `set y axis right' `set y axis increasing' `set y axis decreasing' `set y axis .bottom. .top. [.incBig. [.incSml.]] [labelling .labelling_value.]' `set y axis labels [add] .position_1. "label_1" [.position_2. "label_2" [...]]' `set y axis labels automatic' |
Control various things about the y axis.
set y axis name horizontal'
Make y-axis name be horizontal.
set y axis name vertical'
Make y-axis name be vertical (default).
set y axis left'
Make next y-axis to be drawn have labels to the left of the axis.
set y axis right'
Make next y-axis to be drawn have labels to the right of the axis.
set y axis increasing'
Make next y-axis to be drawn have numeric labels increasing up the page.
This applies only if autoscaling is done; otherwise, the supplied values
(`.left. .right. [.incBig. [.incSml.]]') are used.
set y axis decreasing'
Make next y-axis to be drawn have numeric labels decreasing up the page.
This applies only if autoscaling is done; otherwise, the supplied values
(`.left. .right. [.incBig. [.incSml.]]') are used.
set y axis unknown'
Make Gri forget any existing scale for the y axis, whether set by
another `set y axis' command or automatically, during reading of
data. This is essentially a synonym for `delete y scale'.
set y axis .bottom. .top.'
Make y-axis range from `.bottom.' to `.top.'
set y axis .bottom. .top. .incBig.'
Make y-axis range from `.bottom.' to `.top.', with labelled
increments at `.incBig.'
set y axis .bottom. .top. .incBig. labelling .labelling_value.'
As above, but with the axis labels including the indicated value, and
incremented larger and smaller by `.incBig'. (This does not work
for logarithmic axes.)
set y axis .bottom. .top. .incBig. .incSml.'
Make y-axis range from `.bottom.' to `.top.', with labelled
increments at `.incBig.', and small tics at `.incSml.' NOTE:
if the axis is logarithmic, the value of `.incSml.' takes on a
special meaning: if it is positive then small tics are put at values 2,
3, 4, etc. between the decades, but if `.incSml.' is negative then
no such small tics are used.
set y axis .bottom. .top. .incBig. .incSml. labelling .labelling_value.'
As above, but with the axis labels including the indicated value, and
incremented larger and smaller by `.incBig'. (This does not work
for logarithmic axes.)
set y axis labels .position. "label" [.position. "label" [...]]'
Override the automatic labelling at axis tics, and instead put the
indicated labels at the indicated y values. For example, a
physical-condition axis can be created by the code:
set y axis 0 1 0.5 set y axis labels 0.25 "Weak" 0.75 "Strong" |
The command replaces any existing labels, unless the `add' keyword is present, in which case the new label information is appended to any existing information.
set y axis labels automatic'
Return to automatically-generated axis labels, undoing the command of
the previous item.
set y axis name vertical'
Cause future y axes to be drawn with the name aligned vertically (the default).
set y axis name horizontal'
Cause future y axes to be drawn with the name aligned horizontally.
set y format'
`set y format \format|default|off' |
Set format for numbers on y axis. The format is specified in the manner
of the "C" programming language. The C formats (i.e., `%f',
`%e' and `%lg') are permitted. For example,
`set y format %.1f' tells Gri to use 1 decimal place, and to prefer
the "float" notation to the exponential notation.
The form `set y format off'
tells Gri not to write numbers on the axis. To get spaces in your
format, enclose the format string in double-quotes, e.g., you might use
`set y format "%.0f$\circ$ N"' for a map, or
`set y format "%f"' to make the numbers appear to the right of
their normal location.
The default format is `%lg'.
set y grid'
`set y grid .bottom. .top. .inc.|{/.rows.}'
|
Create y-grid for contour or image. If a grid already exists, an error
will be declared; the way to interpolate from an existing grid to a new
one is with the `interpolate x grid' command.
set y grid .bottom. .top. .inc.'
Create y-grid ranging from the value `.bottom.' at the bottom to
`.top.' at the top, stepping by an increment of `.inc.'.
set y grid .bottom. .top. /.rows.'
Create y-grid with `.rows.' points, ranging from the value
`.bottom.' at the bottom to `.top.' at the top.
set y margin'
`set y margin {[bigger|smaller] .size.}|default'
|
Control y margin, that is, the space between the bottom side of the page and the bottom of the plotting area. (Note that axis labels are drawn inside the margin; the margin extends to the axis line, not to the labels.)
set y margin .size.'
Set bottom margin to `.size.' centimeters. It is permissible to
have negative margins, with the expected effect.
set y margin bigger .size.'
Increases bottom margin by `.size.' centimeters.
set y margin smaller .size.'
Decreases bottom margin by `.size.' centimeters.
set y margin default'
Set bottom margin to default = 6 cm.
set y name'
`set y name "\name"|default' |
Set name of y-axis to the indicated string. An empty string
(`set y name ""') causes the x axis to be unlabelled. The
`default' is `"y"'.
set y size'
`set y size .height_cm.|default' |
Set the width of the plotting area. This does not include axis labels, only the interior part of the plot.
set y size .height_cm.'
Set height of y-axis in centimeters.
set y size default'
Set width of y-axis to default = 10 cm.
set y type'
set y type linear|log|{map N|S|E|W}
|
Control transformation function mapping user units to centimetres on the page.
set y type linear'
Set to linear axis.
set y type log'
Set to log axis. To avoid clashes in the linear to log transform, this
command should precede the creation of an axis scale, either explicitly
through the `set y axis .left. .right. ...' command or implicitly
through the `read columns' command.
set y type map N|S|E|W'
Set to be a map. This means that whole numbers on the axis will have a
degree sign written after them (and then the letter `N', etc), and
that numbers which are multiples of 1/60 will be written in
degree-minute format, and that similarly numbers which are divisible by
1/3600 will be in degree-minute-second format. If none of these things
apply, the axis labels will be written in decimal degrees. Note that
this command overrides any format set by `set y format'.
BUG: this only has an effect if the axis is not already of type
`log'.
set z missing'
set z missing above|below .intercept. .slope. |
Set `z' column to be missing whenever the associated `y' and
`x' columns are above/below the line defined by
y = .intercept. + .slope. * x
