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<head><title>expression -- convert to an expression</title>
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<div><h1>expression -- convert to an expression</h1>
<div class="single"><h2>Synopsis</h2>
<ul><li><div class="list"><dl class="element"><dt class="heading">Usage: </dt><dd class="value"><div><tt>expression x</tt></div>
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<li><div class="single">Inputs:<ul><li><span><tt>x</tt></span></li>
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<li><div class="single">Outputs:<ul><li><span><span>an <a href="___Expression.html">expression</a></span>, constructed from <tt>x</tt> using the mathematical structure of <tt>x</tt>, if present</span></li>
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<div class="single"><h2>Description</h2>
<div>Here is example of a function that expresses small rational numbers as Egyptian fractions using <a href="_expression.html" title="convert to an expression">expression</a>.<table class="examples"><tr><td><pre>i1 : egyptian = method();</pre>
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<tr><td><pre>i2 : egyptian QQ := x -> if x == 0 then 0 else (
n := ceiling(1/x);
expression(1/n) + egyptian(x - 1/n));</pre>
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<tr><td><pre>i3 : egyptian(30/31)
1 1 1 1 1 1
o3 = - + - + - + --- + ----- + ---------
2 3 8 107 15922 633759288
o3 : Expression of class Sum</pre>
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