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Ada Byron's notes on the analytical engine

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Augusta Ada King, Countess of Lovelace (born Ada Byron) is renowned for her description and associated notes on Charles Babbage's design for a mechanical computer called The Analytical Engine. The analytical engine was never built - but Ada's notes are widely recognised as containing the first ever computer program.

History

In 1842 Charles Babbage was invited to give a seminar at the University of Turin about his analytical engine. Luigi Menabrea, a young Italian engineer wrote up Babbage's lecture in French, and this transcript was subsequently published in the Bibliothèque Universelle de Genève in October 1842.

Babbage asked Ada Lovelace (born Ada Byron) to translate Menabrea's paper into English, subsequently requesting that she augment the notes she had added to the translation. Ada spent most of a year doing this. These notes, which are more extensive than Menabrea's paper, were then published in The Ladies Diary and Taylor's Scientific Memoirs (under the initialism A.A.L.).

Content

Her notes were labelled A, B, C, D, E, F and G, the last one being the longest.

In note G Ada describes an algorithm for the analytical engine to compute Bernoulli numbers. It is generally considered the first algorithm ever specifically tailored for implementation on a computer, and for this reason she is considered by many to be the first computer programmer.

Note G could possibly also be said to be the first expression of the modern computer phrase "Garbage In, Garbage Out". Lovelace writes:

"The Analytical Engine has no pretensions whatever to originate anything. It can do whatever we know how to order it to perform. It can follow analysis; but it has no power of anticipating any analytical relations or truths."

According to Linda Talisman on [1]: "Baum [Baum, Joan. The Calculating Passion of Ada Byron. Archon Books, Hamden, Conn., 1986. ISBN 0-208-02119-1] cites:

  • Perl, Teri. The Ladies Diary or Woman's Almanac, 1704-1841, Historica Mathematica 6 (1979): 36-53
  • Wallis, Ruth and Peter. Female Philomaths, Historica Mathematica 7, (1980), 57-64

There were indeed women in mid-century England who signed their names to mathematical articles in popular journals, and there were influential periodicals, such as the Edinburgh Review, that lent intellectual women psychological support.... Although the Ladies Diary ..., the most popular of the mathematical periodicals, encouraged women to join wit with beauty, it attracted serious amateurs of both sexes... [it] was a respectable place to pose mathematical problems and sustain debate... since there were few science periodicals in England until the 1830s, technical articles often appeared in general periodicals like the Ladies Diary. It may have been something similar that originally sparked Mrs. Somerville's interest in mathematics. At a tea party one afternoon, she recalled years later, young Mary Fairfax had been given a ladies' fashion magazine that contained a puzzle, the answer to which was given in strange symbols. These symbols turned out to be algebra. And that magazine became her introduction to the world of Euclidean geometry and number.

Baum, p. 35".