Task: Text Categorization
Input (English): William Walton wrote a set of variations on the Andante from this composer's cello concerto. One of this composer's works opens with a Praeludium in C, includes a series of interludes and fugues, and ends with the Praeludium's retrograde inversion. Besides Ludus Tonalis, this author of The Craft of Musical Composition composed an opera based on E.T.A. Hoffmann's Mademoiselle de Scudri, Cardillac. This composer wrote a requiem based on Whitman's "When Lilacs Last in the Dooryard Bloom'd," as well as Symphonic Metamorphosis on Themes of Von Weber. For 10 points, name this twentieth century German composer of an opera about the painter of the Isenheim Altarpiece, Mathis der Maler.
Output (English): Fine Arts