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Published in:

2021 | OriginalPaper | Chapter

# Visualizing Modular Forms

Author: David Lowry-Duda

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## Abstract

We examine several currently used techniques for visualizing complex-valued functions applied to modular forms. We plot several examples and study the benefits and limitations of each technique. We then introduce a method of visualization that can take advantage of colormaps in Python’s matplotlib library, describe an implementation, and give more examples. Much of this discussion applies to general visualizations of complex-valued functions in the plane.
Footnotes
1
Adjusting the map from magnitude to brightness for SageMath’s complex_plot is possible, but nontrivial; the map is defined internally and the current plotting interface doesn’t give any option to choose or alter this map. In order to adjust this map, it is necessary to modify the source for SageMath’s plotting routines directly.

2
In the period between writing and publishing this paper, the LMFDB changed its method for plotting modular forms to incorporate methods described in this paper. Thus in the rest of this paper, LMFDB-style plots refer to the style of plots in the LMFDB on October 1, 2020.

3
The behavior in Matlab and Maple appears similar, though it is possible to define a color scheme. On the other hand Mathematica has an extensive library of complex plotting color schemes.

Literature
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David Lowry-Duda. phase_mag_plot. https://​github.​com/​davidlowryduda/​phase_​mag_​plot/​, September 2020. [Online; Reference version at https://​doi.​org/​10.​5281/​zenodo.​4035117].
[LMF19]
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