Provided by: stilts_3.1.2-2_all 
NAME
stilts-plot2sphere - Draws a sphere plot
SYNOPSIS
stilts plot2sphere [xpix=<int-value>] [ypix=<int-value>] [insets=<top>,<left>,<bottom>,<right>]
[omode=swing|out|cgi|discard|auto] [storage=simple|cache|basic-cache]
[seq=<suffix>[,...]] [legend=true|false] [legborder=true|false] [legopaque=true|false]
[legseq=<suffix>[,...]] [legpos=<xfrac,yfrac>] [title=<value>] [auxmap=<map-
name>|<color>-<color>[-<color>...]] [auxclip=<lo>,<hi>] [auxflip=true|false]
[auxquant=<number>] [auxfunc=log|linear|sqrt|square] [auxmin=<number>]
[auxmax=<number>] [auxlabel=<text>] [auxcrowd=<factor>] [auxwidth=<pixels>]
[auxvisible=true|false] [forcebitmap=true|false] [compositor=0..1] [animate=<table>]
[afmt=<in-format>] [astream=true|false] [acmd=<cmds>] [parallel=<int-value>]
[crowd=<number>] [frame=true|false] [minor=true|false] [gridaa=true|false]
[texttype=plain|antialias|latex] [fontsize=<int-value>]
[fontstyle=standard|serif|mono] [fontweight=plain|bold|italic|bold_italic]
[cx=<number>] [cy=<number>] [cz=<number>] [scale=<number>] [phi=<degrees>]
[theta=<degrees>] [psi=<degrees>] [zoom=<factor>] [xoff=<pixels>] [yoff=<pixels>]
[zoomfactor=<number>] [leglabelN=<text>] [layerN=<layer-type> <layerN-specific-
params>]
DESCRIPTION
plot2sphere draws plots in an isotropic 3-dimensional space using spherical polar coordinates. The plot‐
ting volume is a cube, which is viewed from the outside and usually bounded by a wire frame annotated by
Cartesian coordinates. This viewing cube is not necessarily centered on the coordinate origin.
This plotting geometry is like that used by plot2cube, but the coordinate unit size is always the same in
the three dimensions, and the coordinates are specified differently.
Positional coordinates are specified as lon, lat, r triples, e.g.: plot2sphere layer1=mark in1=sur‐
vey.fits lon1=RA lat1=DEC r1=REDSHIFT
Content is added to the plot by specifying one or more plot layers using the layerN parameter. The N part
is a suffix applied to all the parameters affecting a given layer; any suffix (including the empty
string) may be used. Available layers for this plot type are: mark, size, sizexy, link2, mark2, label,
contour.
OPTIONS
xpix=<int-value>
Size of the output image in the X direction in pixels. This includes space for any axis labels,
padding and other decoration outside the plot area itself. See also insets.
ypix=<int-value>
Size of the output image in the Y direction in pixels. This includes space for any axis labels,
padding and other decoration outside the plot area itself. See also insets.
insets=<top>,<left>,<bottom>,<right>
Defines the amount of space in pixels around the actual plotting area. This space is used for axis
labels, and other decorations and any left over forms an empty border.
The size and position of the actual plotting area is determined by this parameter along with xpix
and ypix.
The value of this parameter is 4 comma separated integers: <top>,<left>,<bottom>,<right>. Any or
all of these values may be left blank, in which case the corresponding margin will be calculated
automatically according to how much space is required.
omode=swing|out|cgi|discard|auto
Determines how the drawn plot will be output, see SUN/256.
* swing: Plot will be displayed in a window on the screen. This plot is "live"; it can be re‐
sized and (except for old-style plots) navigated around with mouse actions in the same way as
plots in TOPCAT.
* out: Plot will be written to a file given by out using the graphics format given by ofmt.
* cgi: Plot will be written in a way suitable for CGI use direct from a web server. The output
is in the graphics format given by ofmt, preceded by a suitable "Content-type" declaration.
* discard: Plot is drawn, but discarded. There is no output.
* auto: Behaves as swing or out mode depending on presence of out parameter
storage=simple|cache|basic-cache
Determines the way that data is accessed when constructing the plot. There are two basic options,
cached or not.
If no caching is used (simple) then rows are read sequentially from the specified input table(s)
every time they are required. This generally requires a small memory footprint (though that can
depend on how the table is specified) and makes sense if the data only needs to be scanned once or
perhaps if the table is very large.
If caching is used (cache) then the required data is read once from the specified input table(s)
and cached before any plotting is performed, and plots are done using this cached data. This may
use a significant amount of memory for large tables but it's usually more sensible (faster) if the
data will need to be scanned multiple times.
The default value is cache if a live plot is being generated (omode=swing), since in that case the
plot needs to be redrawn every time the user performs plot navigation actions or resizes the win‐
dow, or if animations are being produced. Otherwise (e.g. output to a graphics file) the default
is simple.
seq=<suffix>[,...]
Contains a comma-separated list of layer suffixes to determine the order in which layers are drawn
on the plot. This can affect which symbol are plotted on top of, and so potentially obscure, which
other ones.
When specifying a plot, multiple layers may be specified, each introduced by a parameter layer<N>,
where <N> is a different (arbitrary) suffix labelling the layer, and is appended to all the para‐
meters specific to defining that layer.
By default the layers are drawn on the plot in the order in which the layer* parameters appear on
the command line. However if this parameter is specified, each comma-separated element is inter‐
preted as a layer suffix, giving the ordered list of layers to plot. Every element of the list
must be a suffix with a corresponding layer parameter, but missing or repeated elements are al‐
lowed.
legend=true|false
Whether to draw a legend or not. If no value is supplied, the decision is made automatically: a
legend is drawn only if it would have more than one entry.
legborder=true|false
If true, a line border is drawn around the legend.
legopaque=true|false
If true, the background of the legend is opaque, and the legend obscures any plot components be‐
hind it. Otherwise, it's transparent.
legseq=<suffix>[,...]
Determines which layers are represented in the legend (if present) and in which order they appear.
The legend has a line for each layer label (as determined by the leglabelN parameter). If multiple
layers have the same label, they will contribute to the same entry in the legend, with style icons
plotted over each other. The value of this parameter is a comma-separated sequence of layer suf‐
fixes, which determines the order in which the legend entries appear. Layers with suffixes missing
from this list do not show up in the legend at all.
If no value is supplied (the default), the sequence is the same as the layer plotting sequence
(see seq).
legpos=<xfrac,yfrac>
Determines the internal position of the legend on the plot. The value is a comma-separated pair of
values giving the X and Y positions of the legend within the plotting bounds, so for instance
"0.5,0.5" will put the legend right in the middle of the plot. If no value is supplied, the legend
will appear outside the plot boundary.
title=<value>
Text of a title to be displayed at the top of the plot. If null, the default, no title is shown
and there's more space for the graphics.
auxmap=<map-name>|<color>-<color>[-<color>...]
Color map used for Aux axis shading.
A mixed bag of colour ramps are available: inferno, magma, plasma, viridis, cubehelix, sron, rain‐
bow, rainbow2, rainbow3, pastel, accent, gnuplot, gnuplot2, specxby, set1, paired, hotcold, rdbu,
piyg, brbg, cyan-magenta, red-blue, brg, heat, cold, light, greyscale, colour, standard, bugn,
bupu, orrd, pubu, purd, huecl, hue, intensity, rgb_red, rgb_green, rgb_blue, hsv_h, hsv_s, hsv_v,
yuv_y, yuv_u, yuv_v, scale_hsv_s, scale_hsv_v, scale_yuv_y, mask, blacker, whiter, transparency.
Note: many of these, including rainbow-like ones, are frowned upon by the visualisation community.
You can also construct your own custom colour map by giving a sequence of colour names separated
by minus sign ("-") characters. In this case the ramp is a linear interpolation between each pair
of colours named, using the same syntax as when specifying a colour value. So for instance "yel‐
low-hotpink-#0000ff" would shade from yellow via hot pink to blue.
auxclip=<lo>,<hi>
Defines a subrange of the colour ramp to be used for Aux shading. The value is specified as a
(low,high) comma-separated pair of two numbers between 0 and 1.
If the full range 0,1 is used, the whole range of colours specified by the selected shader will be
used. But if for instance a value of 0,0.5 is given, only those colours at the left hand end of
the ramp will be seen.
If the null (default) value is chosen, a default clip will be used. This generally covers most or
all of the range 0-1 but for colour maps which fade to white, a small proportion of the lower end
may be excluded, to ensure that all the colours are visually distinguishable from a white back‐
ground. This default is usually a good idea if the colour map is being used with something like a
scatter plot, where markers are plotted against a white background. However, for something like a
density map when the whole plotting area is tiled with colours from the map, it may be better to
supply the whole range 0,1 explicitly.
auxflip=true|false
If true, the colour map on the Aux axis will be reversed.
auxquant=<number>
Allows the colour map used for the Aux axis to be quantised. If an integer value N is chosen then
the colour map will be viewed as N discrete evenly-spaced levels, so that only N different colours
will appear in the plot. This can be used to generate a contour-like effect, and may make it easi‐
er to trace the boundaries of regions of interest by eye.
If left blank, the colour map is nominally continuous (though in practice it may be quantised to a
medium-sized number like 256).
auxfunc=log|linear|sqrt|square
Defines the way that values in the Aux range are mapped to the selected colour ramp.
The available options are:
* log: Logarithmic scaling
* linear: Linear scaling
* sqrt: Square root scaling
* square: Square scaling
auxmin=<number>
Minimum value of the data coordinate on the Aux axis. This sets the value before any subranging is
applied. If not supplied, the value is determined from the plotted data.
auxmax=<number>
Maximum value of the data coordinate on the Aux axis. This sets the value before any subranging is
applied. If not supplied, the value is determined from the plotted data.
auxlabel=<text>
Sets the label used to annotate the aux axis, if it is visible.
auxcrowd=<factor>
Determines how closely the tick marks are spaced on the Aux axis, if visible. The default value is
1, meaning normal crowding. Larger values result in more ticks, and smaller values fewer ticks.
Tick marks will not however be spaced so closely that the labels overlap each other, so to get
very closely spaced marks you may need to reduce the font size as well.
auxwidth=<pixels>
Determines the lateral size of the aux colour ramp, if visible, in pixels.
auxvisible=true|false
Determines whether the aux axis colour ramp is displayed alongside the plot.
If not supplied (the default), the aux axis will be visible when aux shading is used in any of the
plotted layers.
forcebitmap=true|false
Affects whether rendering of the data contents of a plot (though not axis labels etc) is always
done to an intermediate bitmap rather than, where possible, being painted using graphics primi‐
tives. This is a rather arcane setting that may nevertheless have noticeable effects on the ap‐
pearance and size of an output graphics file, as well as plotting time. For some types of plot
(e.g. shadingN=auto or shadingN=density) it will have no effect, since this kind of rendering hap‐
pens in any case.
When writing to vector graphics formats (PDF and PostScript), setting it true will force the data
contents to be bitmapped. This may make the output less beautiful (round markers will no longer be
perfectly round), but it may result in a much smaller file if there are very many data points.
When writing to bitmapped output formats (PNG, GIF, JPEG, ...), it fixes shapes to be the same as
seen on the screen rather than be rendered at the mercy of the graphics system, which sometimes
introduces small distortions.
compositor=0..1
Defines how multiple overplotted partially transparent pixels are combined to form a resulting
colour. The way this is used depends on the details of the specified plot.
Currently, this parameter takes a "boost" value in the range 0..1. If the value is zero, satura‐
tion semantics are used: RGB colours are added in proporition to their associated alpha value un‐
til the total alpha is saturated (reaches 1), after which additional pixels have no further ef‐
fect. For larger boost values, the effect is similar, but any non-zero alpha in the output is
boosted to the given minimum value. The effect of this is that even very slightly populated pixels
can be visually distinguished from unpopulated ones which may not be the case for saturation com‐
position.
animate=<table>
If not null, this parameter causes the command to create a sequence of plots instead of just one.
The parameter value is a table with one row for each frame to be produced. Columns in the table
are interpreted as parameters which may take different values for each frame; the column name is
the parameter name, and the value for a given frame is its value from that row. Animating like
this is considerably more efficient than invoking the STILTS command in a loop.
The location of the animation control table. This may take one of the following forms:
* A filename.
* A URL.
* The special value "-", meaning standard input. In this case the input format must be given ex‐
plicitly using the afmt parameter. Note that not all formats can be streamed in this way.
* A system command line with either a "<" character at the start, or a "|" character at the end
("<syscmd" or "syscmd|"). This executes the given pipeline and reads from its standard output.
This will probably only work on unix-like systems.
In any case, compressed data in one of the supported compression formats (gzip, Unix compress or
bzip2) will be decompressed transparently.
afmt=<in-format>
Specifies the format of the animation control table as specified by parameter animate. The known
formats are listed in SUN/256. This flag can be used if you know what format your table is in. If
it has the special value (auto) (the default), then an attempt will be made to detect the format
of the table automatically. This cannot always be done correctly however, in which case the pro‐
gram will exit with an error explaining which formats were attempted.
astream=true|false
If set true, the animation control table specified by the animate parameter will be read as a
stream. It is necessary to give the afmt parameter in this case. Depending on the required opera‐
tions and processing mode, this may cause the read to fail (sometimes it is necessary to read the
table more than once). It is not normally necessary to set this flag; in most cases the data will
be streamed automatically if that is the best thing to do. However it can sometimes result in less
resource usage when processing large files in certain formats (such as VOTable).
acmd=<cmds>
Specifies processing to be performed on the animation control table as specified by parameter ani‐
mate, before any other processing has taken place. The value of this parameter is one or more of
the filter commands described in SUN/256. If more than one is given, they must be separated by
semicolon characters (";"). This parameter can be repeated multiple times on the same command line
to build up a list of processing steps. The sequence of commands given in this way defines the
processing pipeline which is performed on the table.
Commands may alteratively be supplied in an external file, by using the indirection character '@'.
Thus a value of "@filename" causes the file filename to be read for a list of filter commands to
execute. The commands in the file may be separated by newline characters and/or semicolons.
parallel=<int-value>
Determines how many threads will run in parallel if animation output is being produced. Only used
if the animate parameter is supplied. The default value is the number of processors apparently
available to the JVM.
crowd=<number>
Determines how closely tick marks are spaced on the wire frame axes. The default value is 1, mean‐
ing normal crowding. Larger values result in more grid lines, and smaller values in fewer grid
lines.
frame=true|false
If true, a cube wire frame with labelled axes is drawn to indicate the limits of the plotted 3D
region. If false, no wire frame and no axes are drawn.
minor=true|false
If true, minor tick marks are painted along the axes as well as the major tick marks. Minor tick
marks do not have associated grid lines.
gridaa=true|false
If true, grid lines are drawn with antialiasing. Antialiased lines look smoother, but may take
perceptibly longer to draw. Only has any effect for bitmapped output formats.
texttype=plain|antialias|latex
Determines how to turn label text into characters on the plot. Plain and Antialias both take the
text at face value, but Antialias smooths the characters. LaTeX interprets the text as LaTeX
source code and typesets it accordingly.
When not using LaTeX, antialiased text usually looks nicer, but can be perceptibly slower to plot.
At time of writing, on MacOS antialiased text seems to be required to stop the writing coming out
upside-down for non-horizontal text (MacOS java bug).
fontsize=<int-value>
Size of the text font in points.
fontstyle=standard|serif|mono
Font style for text.
The available options are:
* standard
* serif
* mono
fontweight=plain|bold|italic|bold_italic
Font weight for text.
The available options are:
* plain
* bold
* italic
* bold_italic
cx=<number>
Gives the central coordinate in the X dimension. This will be determined from the data range if
not supplied.
cy=<number>
Gives the central coordinate in the Y dimension. This will be determined from the data range if
not supplied.
cz=<number>
Gives the central coordinate in the Z dimension. This will be determined from the data range if
not supplied.
scale=<number>
The length of the cube sides in data coordinates. This will be determined from the data range if
not supplied.
phi=<degrees>
First of the Euler angles, in the ZXZ sequence, defining the rotation of the plotted 3d space.
Units are degrees. This is the rotation around the initial Z axis applied before the plot is
viewed.
theta=<degrees>
Second of the Euler angles, in the ZXZ sequence, defining the rotation of the plotted 3d space.
Units are degrees. This is the rotation towards the viewer.
psi=<degrees>
Second of the Euler angles, in the ZXZ sequence, defining the rotation of the plotted 3d space.
Units are degrees.
zoom=<factor>
Sets the magnification factor at which the the plotted 3D region itself is viewed, without affect‐
ing its contents. The default value is 1, which means the cube fits into the plotting space howev‐
er it is rotated. Much higher zoom factors will result in parts of the plotting region and axes
being drawn outside of the plotting region (so invisible).
xoff=<pixels>
Shifts the whole plot within the plotting region by the given number of pixels in the horizontal
direction.
yoff=<pixels>
Shifts the whole plot within the plotting region by the given number of pixels in the vertical di‐
rection.
zoomfactor=<number>
Sets the amount by which the plot view zooms in or out for each unit of mouse wheel movement. A
value of 1 means that mouse wheel zooming has no effect. A higher value means that the mouse wheel
zooms faster and a value nearer 1 means it zooms slower. Values below 1 are not permitted.
leglabelN=<text>
Sets the presentation label for the layer with a given suffix. This is the text which is displayed
in the legend, if present. Multiple layers may use the same label, in which case they will be com‐
bined to form a single legend entry.
If no value is supplied (the default), the suffix itself is used as the label.
layerN=<layer-type> <layerN-specific-params>
Selects one of the available plot types for layerN. A plot consists of a plotting surface, set up
using the various unsuffixed parameters of the plotting command, and zero or more plot layers.
Each layer is introduced by a parameter with the name layer<N> where the suffix "<N>" is a label
identifying the layer and is appended to all the parameter names which configure that layer. Suf‐
fixes may be any string, including the empty string.
This parameter may take one of the following values, described in more detail in SUN/256:
* mark
* size
* sizexy
* link2
* mark2
* label
* contour
Each of these layer types comes with a list of type-specific parameters to define the details of
that layer, including some or all of the following groups:
* input table parameters (e.g. inN, icmdN)
* coordinate params referring to input table columns (e.g. xN, yN)
* layer style parameters (e.g. shadingN, colorN)
Every parameter notionally carries the same suffix N. However, if the suffix is not present, the
application will try looking for a parameter with the same name with no suffix instead. In this
way, if several layers have the same value for a given parameter (for instance input table), you
can supply it using one unsuffixed parameter to save having to supply several parameters with the
same value but different suffixes.
SEE ALSO
stilts(1)
If the package stilts-doc is installed, the full documentation SUN/256 is available in HTML format:
file:///usr/share/doc/stilts-doc/sun256/index.html
VERSION
STILTS version 3.1-2-debian
This is the Debian version of Stilts, which lack the support of some file formats and network protocols.
For differences see
file:///usr/share/doc/stilts/README.Debian
AUTHOR
Mark Taylor (Bristol University)
Mar 2017 STILTS-PLOT2SPHERE(1)