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<head><title>creating and writing files</title>
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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="_creating_spand_spwriting_spfiles.html" title="">creating and writing files</a></div>
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<div><h1>creating and writing files</h1>
<div>We can print to a file in essentially the same way we print to the screen. In the simplest case, we create the entire file with one command; we give the file name as the initial left hand operand of <a href="__lt_lt.html" title="a binary operator (file output, ...)"><<</a>, and we close the file with <a href="_close.html" title="close a file">close</a>. Files must be closed before they can be used for something else.<table class="examples"><tr><td><pre>i1 : "testfile" << 2^100 << endl << close
o1 = testfile
o1 : File</pre>
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<tr><td><pre>i2 : value get "testfile"
o2 = 1267650600228229401496703205376</pre>
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More complicated files may require printing to the file multiple times. One way to handle this is to assign the open file created the first time we use <a href="__lt_lt.html" title="a binary operator (file output, ...)"><<</a> to a variable, so we can use it for subsequent print operations and for closing the file.<table class="examples"><tr><td><pre>i3 : f = "testfile" << ""
o3 = testfile
o3 : File</pre>
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<tr><td><pre>i4 : f << "hi" << endl
o4 = testfile
o4 : File</pre>
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<tr><td><pre>i5 : f << "ho" << endl
o5 = testfile
o5 : File</pre>
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<tr><td><pre>i6 : f << close
o6 = testfile
o6 : File</pre>
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<tr><td><pre>i7 : get "testfile"
o7 = hi
ho</pre>
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<tr><td><pre>i8 : removeFile "testfile"</pre>
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