Computer programs can handle all sorts of data, from sums of money in bank accounts to sensor readings from scientific instruments. In many cases, the data are a set of discrete elements, such as ...

THIS is a good elementary text-book, founded on the work by M. E. Lagout (“Takimetry”), which we have already noticed (NATURE, vol. xvi. p. 226). The ground covered by the work before us is not quite ...