lwcat - postprocess output of plt to make PostScript, EPS, PDF or PNG
plt -T lw ... | lwcat [ options ... ]
lwcat collects the PostScript
output of plt(1)
and adds a prolog and epilog to create a complete PostScript
document (or another format, if appropriate options have been selected).
It is possible to concatenate the outputs of two or more plt runs to be
processed as a single job by lwcat; see the plt Tutorial and Cookbook
By default, lwcat sends its output directly to
the default printer via lpr. These options may be used to modify this behavior:
- Send the output to the printer, but don’t eject the page (use this option
if you wish to overlay the output with additional material to be produced
by another program).
- Write PostScript to the standard output (not to
- Write PostScript to a temporary file and view it with
- Same as -psv.
- Write EPSF (encapsulated PostScript
format) to the standard output. Note that this is only a close approximation
to EPSF; it is acceptable to LaTeX’s epsfig package, at least.
PDF (portable document format) to the standard output.
- Write PNG (portable
network graphics) format to the standard output.
the output appears within a 6.75x6 inch (171x152 mm) window, the lower left
corner of which is positioned 1 inch (25.4 mm) from the left edge and 3.5
inches (89 mm) from the bottom edge of the page. The following options
may be used to modify the size, location, and orientation of the output:
- Use landscape mode (rotate plot 90 degrees counterclockwise).
- Plot in a 6x6 inch (152x152 mm) square window, 1.25 inches (32 mm) from
the left edge and 3.5 inches (89 mm) from the bottom edge of the page.
- Plot in a 6.25x6.25 inch (159x159 mm) square window, positioned as for -sq.
- Plot in a 6.25x4 inch (159x102 mm) window, positioned as for -sq.
- Plot in a 4.75x3.15 inch (121x80 mm) window, positioned as for -sq.
in a 4.5x5.5 inch (114x140 mm) window, 2.5 inches (63 mm) from the left and
bottom edges of the page.
- Plot in a 7x9.5 inch (178x241 mm) window, 0.75
inches (19 mm) from the left and bottom edges of the page (centered on
a US letter sheet).
- Plot in a 7x8.5 inch (178x216 mm) window, positioned
as for -v.
- Plot in a 190x275 mm window, centered on an A4 sheet.
- Plot in a 7.5x10 inch (191x254 mm) window, centered on a US letter sheet.
- Plot in a 7.5x5 inch (191x127 mm) window, 0.5 inches (12.7 mm) from
the left edge and 3 inches (76 mm) from the bottom edge of the page (3:2
aspect ratio, as for 35 mm slides).
- Plot in a 7.5x5.625 inch (191x143
mm) window, 0.5 inches (12.7 mm) from the left edge and 2.375 inches (60 mm)
from the bottom edge of the page (4:3 screen aspect ratio).
in a 7.5x4.635 inch (191x118 mm) window, 0.5 inches (12.7 mm) from the left
edge and 3.365 inches (85 mm) from the bottom edge of the page (the aspect
ratio is approximately the "golden ratio", (1+sqrt(5))/2 = 1.61803 ...).
- Plot in an 8x0.8 inch (203x20 mm) window.
- -custom width height left-margin
- Plot in a custom window. The -custom option reads
up to 5 arguments that follow it. If one of the 5 arguments immediately
following -custom begins with ’-’, it and any remaining arguments are treated
as ordinary options, and default values are used for any missing options.
The units of width, height, and margins are inches, and the font scale
is a dimensionless factor with a default value of 1 that can be used to
enlarge or shrink any text in the plot. The defaults for width and left-margin
are 5 and 0 respectively, and the defaults for height and bottom-margin
are the values assigned to width and left-margin (whether explicitly or
Other window options can be easily added; see the source for lwcat for
By default, lwcat prints a single copy. Multiple copies
can be produced using the options -c2, -c3, -c4, -c5, and -c6; when using a
PostScript printer, this will almost always be much faster than rerunning
lwcat, since the document is downloaded and rasterized only once when using
these options. To print more than 6 copies, repeat or combine these options
- PostScript prolog
is available as part of the plt package in PhysioToolkit (see SOURCE below)
under the GPL.
Paul Albrecht and George B. Moody (email@example.com)
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Updated 8 March 2019