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[http://www.freemove.it/images/MimeTexPreview.gif]

[FF] 2007-05-13 I remember some people asked about displaying '''mathematical formula''' in Tcl. Some implemented typesetting-like systems in pure Tcl. Cause I don't like re-inventing the wheel I preferred using a well known working system, based on a well known typesetting language: [TeX] (more precisely, the math extensions).

Btw the [TeX] distribution can be quite huge, and sometimes troublesome to install on non-UNIX-like systems (see Windows).

Fortunately a nice small application here comes in help: [mimetex].

[mimetex] is mainly used in the CGI form, e.g. wikis and forums, to display mathematical formulae (see Wikipedia for a live example). Anyway it can be compiled as a standalone executable, producing nice [GIF] (anti-aliased, if you want it) output.

The script below it is just an example on how to embed it for using into a canvas.

I addressed several problems, like working with live iostreams, base64 encoding, and without producing intermediate temporary files. Feel free to improve it (and post it here) if you like.

See also: [Rendering mathematical formulae] for an alternative example, not using TeX at all.

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 #!/bin/sh
 # This line continues for Tcl, but is a single line for 'sh' \
 exec tclsh "$0" ${1+"$@"}
 
 package require base64
 
 set img {}
 #set mimetex_bin "c:/mimetex/mt.exe"
 set mimetex_bin "mimetex"
 
 proc render e {
     global img
     .c delete eee
     catch {image delete $img}
     set p [open [list |$::mimetex_bin -d $e] r]
     fconfigure $p -translation binary -encoding binary
     set rawData [base64::encode [read $p]]
     close $p
     set img [image create photo -data $rawData]
     .c create image 10 10 -image $img -tags eee -anchor nw
 }
 
 grid [canvas .c] -row 0 -columnspan 2 -sticky news
 grid [entry .t -textvariable ee] -row 1 -column 0 -sticky we
 grid [button .b -command {render $ee} -text Render] -row 1 -column 1
 grid columnconfigure . 0 -weight 1
 grid rowconfigure . 0 -weight 1
 set ee "x_{1,2}=\\frac{-b \\pm \\sqrt{b^2 - 4ac}}{2a}"
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[[
[Category Mathematics] |
[Category Graphics]
]]