Directions for IFS of Fractal Images

Find the rules to generate the images on the Fractal Image Sheet.

While practicing, it may help to enclose the image in a square, taken to be of side length 1.

To identify reduced copies, subdividing the square may be helpful. In some exercises you may need squares of different sizes.

The Sierpinski gasket enclosed in a square, and divided into four subsquares.

Find values for r, s, theta, e and f, recalling these conditions.

*r and s are decimals between -1 and 1
*r = s for pieces similar to the whole
*negative r reflects across the y-axis, negative s reflects across the x-axis
*theta, measured in degrees, specifies the rotation about the origin
*positive theta is counter-clockwise, negative is clockwise
*e specifies horizontal translation, f specifies vertical

To understand the effect of each transformation, we adopt this convention:

After determining the values of r, s, theta, e, and f for each part of a fractal, run the IFS program with those values.

If the image generated matches the fractal, you are seeking you have been successful; if not, use the differences in the fractals to find the errors in your values. This process may take several tries.

If finding values for a picture is difficult, here are two approaches for building intuition. The first uses paper and scissors, the second uses the web and graphics software.

First approach

Second approach

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