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<div><a href="index.html" title="">Macaulay2Doc</a> > <a href="___The_sp__Macaulay2_splanguage.html" title="">The Macaulay2 language</a> > <a href="_variables.html" title="The variables of a complex or co-complex.">variables</a> > <a href="_subscripted_spvariables.html" title="">subscripted variables</a></div>
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<div><h1>subscripted variables</h1>
<div>It is common in mathematics to use subscripted variables. We use the underscore to represent subscripts. If we haven't assigned a value to <tt>x</tt> we may simply start using it as a subscripted variable. The subscripts can be anything.<table class="examples"><tr><td><pre>i1 : x
o1 = x
o1 : Symbol</pre>
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<tr><td><pre>i2 : x_4
o2 = x
4
o2 : IndexedVariable</pre>
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<tr><td><pre>i3 : x_(2,3)
o3 = x
2,3
o3 : IndexedVariable</pre>
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The <a href="_...html" title="a binary operator, used for sequences of consecutive items">..</a> operator knows what to do with subscripted variables.<table class="examples"><tr><td><pre>i4 : x_10 .. x_20
o4 = (x , x , x , x , x , x , x , x , x , x , x )
10 11 12 13 14 15 16 17 18 19 20
o4 : Sequence</pre>
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<tr><td><pre>i5 : x_(1,1) .. x_(2,3)
o5 = (x , x , x , x , x , x )
1,1 1,2 1,3 2,1 2,2 2,3
o5 : Sequence</pre>
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Values can be assigned to these variables with <a href="__us.html" title="a binary operator, used for subscripting and access to elements">_</a>.<table class="examples"><tr><td><pre>i6 : y_10 = 555;</pre>
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<tr><td><pre>i7 : y_10
o7 = 555</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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