Fourier analysis 44 Mathematics 5 Fourier transformations 4 Differential equations, partial 3 Harmonic analysis 3 Approximation theory 2 Fourier series 2 Hardy spaces 2 Numerical analysis 2 Sampling (Statistics) 2 Signal processing 2 Asymptotic expansions 1 Clifford algebras 1 Convergence 1 Data processing 1 Differential equations, Nonlinear 1 Differential equations, Partial 1 Dirichlet forms 1 Eigenvalues 1 Finite groups 1 Functional analysis 1 Functions 1 Functions, Continuous 1 Functions, Entire 1 Functions, special 1 Markov processes 1 Martingales (Mathematics) 1 Maximum entropy method 1 Non-Abelian groups 1 Number theory 1