Fourier coefficients. Tests for the convergence of Fourier series
2.1. Operations on Fourier series.
2.2. Modulus of continuity. Fourier coefficients.
2.3. Formulae for partial sums.
2.4. Dini's test.
2.5. Theorems on localization.
2.6. Functions of bounded variation.
2.7. Tests of Lebesgue and Dini-Lipschitz.
2.8. Tests of de la Vallée-Poussin, Young, and Hardy and Littlewood.
2.9. Miscellaneous theorems and examples.