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<head><title>Symbol _ Thing = Thing -- assignment to an indexed variable</title>
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<div><h1>Symbol _ Thing = Thing -- assignment to an indexed variable</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>x_a = v</tt></div>
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<li><span>Operator: <a href="__us.html" title="a binary operator, used for subscripting and access to elements">_</a></span></li>
<li><div class="single">Inputs:<ul><li><span><tt>x</tt>, <span>a <a href="___Symbol.html">symbol</a></span></span></li>
<li><span><tt>a</tt>, <span>a <a href="___Thing.html">thing</a></span></span></li>
<li><span><tt>v</tt>, <span>a <a href="___Thing.html">thing</a></span></span></li>
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<li><div class="single">Consequences:<ul><li>the indexed variable <tt>x_a</tt> is assigned the value <tt>v</tt>.</li>
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<li><div class="single">Outputs:<ul><li><span><tt>v</tt></span></li>
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<div class="single"><h2>Description</h2>
<div><table class="examples"><tr><td><pre>i1 : x_a
o1 = x
a
o1 : IndexedVariable</pre>
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<tr><td><pre>i2 : x_a = b
o2 = b
o2 : Symbol</pre>
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<tr><td><pre>i3 : x_a
o3 = b
o3 : Symbol</pre>
</td></tr>
<tr><td><pre>i4 : x_c
o4 = x
c
o4 : IndexedVariable</pre>
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<tr><td><pre>i5 : x_c = d
o5 = d
o5 : Symbol</pre>
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<tr><td><pre>i6 : x_c
o6 = d
o6 : Symbol</pre>
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The source code explains how it works, behind the scences.<pre> -- code for method: Symbol _ Thing
../../m2/variables.m2:44:25-44:56: --source code:
Symbol _ Thing := (X,i) -> new IndexedVariable from {X,i}
---------------------------------
-- code for method: Symbol _ Thing = Thing
../../m2/variables.m2:52:26-55:13: --source code:
Symbol _ Thing = (x,i,e) -> (
x' := value x;
if not instance(x',IndexedVariableTable) then x' = new IndexedVariableTable from x;
x'_i = e)</pre>
<table class="examples"><tr><td><pre>i7 : peek x
o7 = IndexedVariableTable{a => b }
c => d
symbol$ => x</pre>
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<div class="single"><h2>See also</h2>
<ul><li><span><a href="___Indexed__Variable.html" title="the class of all indexed variables">IndexedVariable</a> -- the class of all indexed variables</span></li>
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