Geared toward mathematicians already familiar with the elements of Lebesgue's theory of integration, this classic, graduate-level text begins with a brief introduction to some generalities about trigonometrical series. Discussions of the Fourier series in Hilbert space lead to an examination of further properties of trigonometrical Fourier series, concluding with a detailed look at the applications of previously outlined theorems. Ideally suited for both individual and classroom study.

English mathematician G. H. Hardy (1877?1974) is famous for his achievements in number theory and mathematical analysis. The author of the 1940 essay "A Mathematician's Apology," he was a mentor of the mathematical genius Srinivasa Ramnujan.