28 lines
3.3 KiB
HTML
28 lines
3.3 KiB
HTML
<?xml version="1.0" encoding="ISO-8859-1" standalone="no"?>
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<html xmlns="http://www.w3.org/1999/xhtml"><head><title>0</title><link rel="stylesheet" href="../../jargon.css" type="text/css"/><meta name="generator" content="DocBook XSL Stylesheets V1.61.0"/><link rel="home" href="../index.html" title="The Jargon File"/><link rel="up" href="../0.html" title="0"/><link rel="previous" href="me.html" title="/me"/><link rel="next" href="one-TBS.html" title="1TBS"/></head><body><div class="navheader"><table width="100%" summary="Navigation header"><tr><th colspan="3" align="center">0</th></tr><tr><td width="20%" align="left"><a accesskey="p" href="me.html">Prev</a> </td><th width="60%" align="center">0</th><td width="20%" align="right"> <a accesskey="n" href="one-TBS.html">Next</a></td></tr></table><hr/></div><dt><a id="numeral-zero"/><dt xmlns="" id="numeral-zero"><b>0</b></dt></dt><dd><p> Numeric zero, as opposed to the letter ‘O’ (the 15th
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letter of the English alphabet). In their unmodified forms they look a lot
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alike, and various kluges invented to make them visually distinct have
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compounded the confusion. If your zero is center-dotted and letter-O is
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not, or if letter-O looks almost rectangular but zero looks more like an
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American football stood on end (or the reverse), you're probably looking at
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a modern character display (though the dotted zero seems to have originated
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as an option on IBM 3270 controllers). If your zero is slashed but
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letter-O is not, you're probably looking at an old-style ASCII graphic set
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descended from the default typewheel on the venerable ASR-33 Teletype
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(Scandinavians, for whom Ø is a letter, curse this arrangement).
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(Interestingly, the slashed zero long predates computers; Florian Cajori's
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monumental <i class="citetitle">A History of Mathematical Notations</i> notes
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that it was used in the twelfth and thirteenth centuries.) If letter-O has
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a slash across it and the zero does not, your display is tuned for a very
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old convention used at IBM and a few other early mainframe makers
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(Scandinavians curse <span class="emphasis"><em>this</em></span> arrangement even more,
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because it means two of their letters collide). Some Burroughs/Unisys
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equipment displays a zero with a <span class="emphasis"><em>reversed</em></span> slash. Old
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CDC computers rendered letter O as an unbroken oval and 0 as an oval broken
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at upper right and lower left. And yet another convention common on early
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line printers left zero unornamented but added a tail or hook to the
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letter-O so that it resembled an inverted Q or cursive capital letter-O
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(this was endorsed by a draft ANSI standard for how to draw ASCII
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characters, but the final standard changed the distinguisher to a tick-mark
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in the upper-left corner). Are we sufficiently confused yet?</p></dd><div class="navfooter"><hr/><table width="100%" summary="Navigation footer"><tr><td width="40%" align="left"><a accesskey="p" href="me.html">Prev</a> </td><td width="20%" align="center"><a accesskey="u" href="../0.html">Up</a></td><td width="40%" align="right"> <a accesskey="n" href="one-TBS.html">Next</a></td></tr><tr><td width="40%" align="left" valign="top">/me </td><td width="20%" align="center"><a accesskey="h" href="../index.html">Home</a></td><td width="40%" align="right" valign="top"> 1TBS</td></tr></table></div></body></html>
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