Number data elements include a variety of data all of which are stored and manipulated by Gnumeric as numbers. This includes integers, decimal fractions, general fractions, numbers in scientific notation, dates, times, and currency values.
Data are recognized as numbers when they are entered, dependent on the format of the sequence of characters entered. Gnumeric attempts to intelligently guess the subtype of the data and match the data to an existing format for numbered data. If it matches a data format, Gnumeric will automatically assign the datum to a data type and associate an appropriate display format with the cell. The format recognition of Gnumeric includes a wide variety of data formats which are discussed in detail in Section 5.10.1 ― Number Formatting Tab.
Because Gnumeric automatically guesses the data type of a number being entered into a cell, this process may have to be over-ridden for certain types of data. For example, postal codes in the United States consist of a sequence of numbers which Gnumeric interprets as an integer. However, U.S. postal codes can start with a leading zero which Gnumeric discards by default. In order to override the default format, the number format of the cell must be specified before the entry of the data. This is explained in Section 5.10.1 ― Number Formatting Tab, below.