Functions with Multiple Periods 

Functions with multiple variables can have multiple periods.

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Tesselating rectangles split the plane into regions where the function repeats.

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A function of a single complex variable can have two periods, in two different complex directions.

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Adding either of these periods to the input variable will leave the function unchanged.

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However, in this example the two complex directions are not perpendicular.

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This means that the repeating blocks in the complex plane are parallelograms rather than rectangles.

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