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:I tried to fix it. Is it OK now? [[User:JRSpriggs|JRSpriggs]] ([[User talk:JRSpriggs|talk]]) 22:57, 22 December 2021 (UTC)
:: Yes, now OK [[User:Jumpow|Jumpow]] ([[User talk:Jumpow|talk]]) 21:33, 4 January 2022 (UTC)
== Friden calculator algorithms ==
The Friden desktop mechanical calculator model SRW computed square roots fundamentally by subtracting consecutive odd integers. It first multiplied S by 5, then used much of the division to subtract 5 times the consecutive odd integers as 5, 15, 25, 35, etc. until division overdraft and its correction were followed by a carriage shift. The process was repeated for the next digit.
Working with values 5x those of the basis method made the mechanism practical, with minimum modification of the keyboard and division hardware.
Friden's electronic EC–132 calculator did the equivalent of consecutive odd integers by subtracting twice for each minuend increment. The first of the two subtroctions was always by one. The second minuend (iirc!) started at zero, and accumulated by two, until overdraft. That increbentitg by tmo was done by twice incremeting by one, simpler than by an explicit two.
That calculahor had no adder (!). Arithmetic was done by counting pulses. Its ultrasonic wire delay line stored digits as radix one; a nine was nine consecutive pulses. Logic to add one pulse to a stored digit was quite lixely simpler than for adding two in a given part of a cycle. [[Special:Contributions/2600:4040:500C:1C00:CD83:34B:5FF1:895F|2600:4040:500C:1C00:CD83:34B:5FF1:895F]] ([[User talk:2600:4040:500C:1C00:CD83:34B:5FF1:895F|talk]]) 10:52, 16 February 2022 (UTC)
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