Lock a Variable

Lock a Variable

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When you draw an ellipse this way using real pins, pencil, and string, the length of the string cant change. To emulate this real-world behavior, we can lock the value of the variable L.

  1. In the Variables list, select L and click the lock icon below the list. A plus sign (+) appears next to the locked variable in the Locked column.

Tutorial 2 (value of L locked) 

  1. Select points A or C and drag them. With the length of the string constant, B traces the same locus no matter which point you drag.