22.2. Lookup Auxiliary Tables

In the old days, when engineers used slide rules, other people went to the back of their math and financial book to use printed tables of functions. Here you could find trigonometry, or compound interest, or statistical functions. Today, you would more likely calculate the function, because computing power is so cheap. Pocket calculators that sold for hundreds of dollars in the 1960s are now on spikes in the checkout line at office supply stores.

In the days of keypunch data entry, there would be loose-leaf notebooks of the encoding schemes to use sitting next to the incoming paper forms. Today, you would more likely see a WIMP (Windows, Icons, Menus, and Pulldowns) interface.

While the physical mechanisms have ...

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