Fourier transform

A basic examples of the Fourier transform of a rectangular function.
For more Fourier analysis figures, please see the “fourier analysis” tag. These figures are used in Ben Kilminster’s lecture notes for PHY111.

Edit and compile if you like:

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% Author: Izaak Neutelings (January 2021)
% http://pgfplots.net/tikz/examples/fourier-transform/
% https://tex.stackexchange.com/questions/127375/replicate-the-fourier-transform-time-frequency-domains-correspondence-illustrati
% https://www.dspguide.com/ch13/4.htm
\documentclass[border=3pt,tikz]{standalone}
\usepackage{amsmath}
\usepackage{tikz}
\usepackage{physics}
\usepackage[outline]{contour} % glow around text
\usepackage{xcolor}
\usetikzlibrary{intersections}
\usetikzlibrary{decorations.markings}
\usetikzlibrary{angles,quotes} % for pic
\usetikzlibrary{calc}
\usetikzlibrary{3d}
\contourlength{1.3pt}
\tikzset{>=latex} % for LaTeX arrow head
\colorlet{myred}{red!85!black}
\colorlet{myblue}{blue!80!black}
\colorlet{mycyan}{cyan!80!black}
\colorlet{mygreen}{green!70!black}
\colorlet{myorange}{orange!90!black!80}
\colorlet{mypurple}{red!50!blue!90!black!80}
\colorlet{mydarkred}{myred!80!black}
\colorlet{mydarkblue}{myblue!80!black}
\tikzstyle{xline}=[myblue,thick]
\def\tick#1#2{\draw[thick] (#1) ++ (#2:0.1) --++ (#2-180:0.2)}
\tikzstyle{myarr}=[myblue!50,-{Latex[length=3,width=2]}]
\def\N{80}
\begin{document}
% RECTANGULAR FUNCTION
\def\xmin{-0.7*\T} % min x axis
\def\xmax{3.0}     % max x axis
\def\ymin{-0.4}    % min y axis
\def\ymax{1.7}     % max y axis
\def\A{0.67*\ymax} % amplitude
\def\T{0.31*\xmax} % period
 
 
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