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<h1><img hspace=10 src="bang.gif"> Sign of Determinants Example</h1>
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<h2>Sign of Determinants</h2>
The sign determination of determinants of 3 x 3 or 4 x 4 matrices is
the one of the most fundamental computations in the computational
geometry. Consider the 4 x 4 matrix:
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<img src="Mat1.gif">
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The determinant of this matrix is 0.
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Now, perturb the bottom right element:
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<img src="Mat2.gif">
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Then, the determinant becomes <em>negative</em>.
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The results are
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<img src="Det_rlt.gif">
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<a href="Det_src.html" target=NEW_WINDOW>Take a look at code.</a>
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[ <a href="exact.html"><strong>Real/Expr</strong> Homepage</a> ]
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<address>
Should you have any comment, send an e-mail to
<a href="mailto:ouchi@simulation.nyu.edu">
ouchi@simulation.nyu.edu.
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