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<head><title>IndexedVariable -- the class of all indexed variables</title>
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<div><h1>IndexedVariable -- the class of all indexed variables</h1>
<div class="single"><h2>Description</h2>
<div>Indexed variables provide the possibility of producing polynomial rings <tt>R[x_0, x_1, ..., x_(n-1)]</tt> in n variables, where n is not known in advance. If <tt>x</tt> is an symbol, and i is an integer, then <tt>x_i</tt> produces an indexed variable. After this has been done, an assignment <tt>x_i=v</tt> will assign another value to it. A new sequence of indexed variables of length n assigned to the symbol <tt>x</tt> can be produced with <tt>x_1 .. x_n</tt> and that sequence can be used in constructing a polynomial ring.<table class="examples"><tr><td><pre>i1 : ZZ/101[t_0 .. t_4]
ZZ
o1 = ---[t , t , t , t , t ]
101 0 1 2 3 4
o1 : PolynomialRing</pre>
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<tr><td><pre>i2 : (t_0 - 2*t_1)^3
3 2 2 3
o2 = t - 6t t + 12t t - 8t
0 0 1 0 1 1
ZZ
o2 : ---[t , t , t , t , t ]
101 0 1 2 3 4</pre>
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Warning: the values of the indexed variables <tt>t_i</tt> are stored in a global location, behind the scenes, so may not get garbage collected, even if <tt>t</tt> is a local variable.</div>
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<div class="waystouse"><h2>Methods that use an indexed variable :</h2>
<ul><li><span>IndexedVariable <- Thing, see <span><a href="__lt-.html" title="assignment with left side evaluated"><-</a> -- assignment with left side evaluated</span></span></li>
<li><span>IndexedVariable ? IndexedVariable, see <span><a href="__qu.html" title="comparison operator">?</a> -- comparison operator</span></span></li>
<li><span>Symbol ? IndexedVariable, see <span><a href="__qu.html" title="comparison operator">?</a> -- comparison operator</span></span></li>
<li><span>baseName(IndexedVariable), see <span><a href="_base__Name.html" title="the base name of a generator">baseName</a> -- the base name of a generator</span></span></li>
<li><span><a href="___Indexed__Variable_sp.._sp__Indexed__Variable.html" title="sequences of consecutive indexed variables">IndexedVariable .. IndexedVariable</a> -- sequences of consecutive indexed variables</span></li>
<li><span><a href="___Indexed__Variable_sp.._lt_sp__Indexed__Variable.html" title="sequences of consecutive indexed variables">IndexedVariable ..< IndexedVariable</a> -- sequences of consecutive indexed variables</span></li>
<li><span><a href="___Indexed__Variable_sp_us_sp__Ring.html" title="get a ring variable by name">IndexedVariable _ Ring</a> -- get a ring variable by name</span></li>
<li><span><a href="_value_lp__Indexed__Variable_rp.html" title="retrieve the value of an indexed variable">value(IndexedVariable)</a> -- retrieve the value of an indexed variable</span></li>
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<div class="waystouse"><h2>For the programmer</h2>
<p>The object <a href="___Indexed__Variable.html" title="the class of all indexed variables">IndexedVariable</a> is <span>a <a href="___Type.html">type</a></span>, with ancestor classes <a href="___Basic__List.html" title="the class of all basic lists">BasicList</a> < <a href="___Thing.html" title="the class of all things">Thing</a>.</p>
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