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2011-02-01T00:00:01
<mdoxml version="1.0"><p><span class="editorial">Beginners to LOGO programming may want to start by working through the <a href="https://nrich.maths.org/8045">FIRST FORWARD series of introductory articles</a> before tackling this problem.</span></p>
<p> </p>
<p> </p>
<h4>Going Loopy</h4>
<p>Spiralling out of control! I should have known better. Merely mentioning the word spiral and suggestions and reminders abound. Below are some spirals done by pupils at a recent Masterclass at the University of Wales . Bangor.</p>
<p>In each case the 'unit' spiral has formed a closed LOOP.</p>
<table cellpadding="20">
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<td><mdo:image alt="" src="pic1.gif"></mdo:image></td>
<td><mdo:image alt="" src="pic2.gif"></mdo:image></td>
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<td><mdo:image alt="" src="pic3.gif"></mdo:image></td>
<td><mdo:image alt="" src="pic4.gif"></mdo:image></td>
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<p>The basic procedure used was:</p>
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<pre>
<strong>TO SPIRAL :S :A
IF :S > 40 [STOP]
FD :S RT :A
SPIRAL :S + 5 :A
END
</strong>
</pre></td>
<td align="right" valign="center"><em>n.b. this will stop the spiral becoming too large.</em></td>
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<p>You might like to replicate the spirals above by considering suitable values for the variables <strong>:S</strong> and <strong>:A</strong> and THEN repeating your procedure several times more!</p>
<p>Or better still you might like to design spirals and loops based on your own ideas!</p>
<p>Or you might like to investigate changes to the size of the angle in ...</p>
<pre>
<strong>TO SPIRAL :S :A
FD :S RT :A
SPIRAL :S + 1 :A + 5
END
</strong>
</pre></mdoxml>
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Going Loopy
Imported legacy Object
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