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Edward W. Veitch (September 8, 1924 – December 23, 2013) was an American computer scientist. He graduated from Harvard University in 1946 with a degree in Physics, followed by graduate degrees from Harvard in Physics and Applied Physics in 1948 and 1949 respectively. In his 1952 paper "A Chart Method for Simplifying Truth Functions", Veitch described a graphical procedure for the optimization of logic circuits, a year later (1953) refined in a paper by Maurice Karnaugh into what is now known as the ''Karnaugh map'' method. ==Recent comments on design== Recently Veitch wrote about the development of the Veitch diagram and its interpretation, These comments are summarized here. *The problem is how to depict a Boolean function of ''n'' variables so the human eye can easily see how to simplify the function. * *A function of four variables has sixteen input combinations and the diagram has sixteen different squares to be filled from the truth table that defines the function. * *The primary difference between the Veitch and Karnaugh versions is that the Veitch diagram presents the data in the binary sequence used in the truth table while the Karnaugh map interchanges the third and fourth rows and the third and fourth columns. * *The general digital computer community chose the Karnaugh approach. Veitch accepted this decision, even though in early 1952, before his presentation, he had almost changed to that approach but decided against it. A few years later several textbooks described the K-map, a few of them designating it a Veitch diagram. Years later (1999) Veitch discovered that Wikipedia had an article on the K-map. He read it and reread his 1952 paper. He realized that his old paper did not describe his method for finding simplification patterns. He now believes that the readers of his paper believed that he found simplifications by looking at the column and row labels while the K-map user found the simplification groups from a set of rules and then used the labels only to identify the groups. Veitch also believes that a change he made in his diagram just before his presentation made it more difficult for the reader to realize his rules for finding simplification groups. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Edward W. Veitch」の詳細全文を読む スポンサード リンク
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