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eqn2graph(1)


NAME

   eqn2graph - convert an EQN equation into a cropped image

SYNOPSIS

   eqn2graph [ -unsafe ] [ -format fmt ]

DESCRIPTION

   Reads  an  EQN equation (one line) as input; produces an image file (by
   default in Portable Network Graphics format) suitable for  the  Web  as
   output.

   Your  input EQN code should not have the .EQ/.EN preamble that normally
   precedes it within groff(1) macros; nor do you need to have dollar-sign
   or other delimiters around the equation.

   The  output image will be clipped to the smallest possible bounding box
   that contains all the black pixels.  Older versions of convert(1)  will
   produce  a  black-on-white  graphic; newer ones may produce a black-on-
   transparent graphic.  By specifying command-line options to  be  passed
   to   convert(1)  you  can  give  it  a  border,  force  the  background
   transparent, set the image's pixel density,  or  perform  other  useful
   transformations.

   This  program  uses  eqn(1),  groff(1),  and the ImageMagick convert(1)
   program.   These  programs  must  be  installed  on  your  system   and
   accessible on your $PATH for eqn2graph to work.

OPTIONS

   -unsafe
          Run  groff(1)  in the `unsafe' mode enabling the PIC macro sh to
          execute arbitrary commands.  The default is to forbid this.

   -format fmt
          Specify an output format; the default is PNG  (Portable  Network
          Graphics).  Any format that convert(1) can emit is supported.

   Command-line  switches  and  arguments  not  listed above are passed to
   convert(1).

FILES

   /usr/share/groff/1.22.3/tmac/eqnrc
          The eqn(1) initialization file.

ENVIRONMENT

   GROFF_TMPDIR
          The directory in which temporary files will be created.  If this
          is  not set eqn2graph searches the environment variables TMPDIR,
          TMP, and TEMP (in that order).  Otherwise, temporary files  will
          be created in /tmp.

BUGS

   Due  to changes in the behavior of ImageMagick convert(1) that are both
   forward and backward-incompatible, mismatches  between  your  eqn2graph
   and  convert(1)  versions  may  produce  zero-sized or untrimmed output
   images.  For this version of eqn2graph  you  will  need  a  version  of
   convert(1)  that supports the -trim option; older versions of eqn2graph
   used -crop 0x0, which no longer has trimming behavior.

SEE ALSO

   pic2graph(1), grap2graph(1), eqn(1), groff(1), gs(1), convert(1).

AUTHORS

   Eric S. Raymond <esr@thyrsus.com>.  This documentation is released to
   the public domain.



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