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Babbage's Difference Engine No. 2

The Difference Engine was an accurate mechanical calculator designed by Charles Babbage in the 1840s, but was never built in its inventor's lifetime. Here, its modern builder explains how it works.  
 
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singedrac (1 day ago) Show Hide
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Can it run Crysis?
lawiley (4 days ago) Show Hide
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I think we are missing the bigger point. This is the beginning of the idea that machines can be used for calculations. The next step after the slide rule and the abacus. The industrialization of calculation.
SirCoolness (4 days ago) Show Hide
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The problem with machinery like this is that it's expensive. At the time it would have been practical in that it could have resulted in accurate calculations for the people it was available to. Keyword: availability. This machine costs a huge amount of money. It took 17 years for the owner to acquire the money necessary to build it. The advancements we have made technologically allow for computing devices to be made available to almost everyone. But I agree that they could try to look nicer.
Philomathie (3 days ago) Show Hide
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You only need one difference engine to produce a tabulated book of results which can then be copied as many times as needed. Considering the amount of time that would have been spent in those days trying to calculate the same problems (BY HAND I might add) this would be well worth it because of the time saved and the inherent accuracy in the results which reduce errors.
freq32 (4 days ago) Show Hide
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this machine was built recently out of materials that were available back during that time period. it wasn't built in the 1800's.

Sadly, Babbage never finished his version due to lack of money.
RedNifre (2 weeks ago) Show Hide
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The storage is about 103Byte and it runs at 0FLOPS since it doesn't have floating point numbers. :)

You can calculate it like this:
(Log_2 ( 10 ^ (Columns * Digits) ) ) / BitsPerByte

this means:
(Log_2( 10 ^ (8 * 31) ) ) / 8

Since this is tricky for most calculators you can simply it to this:

248 / Log(2) / 8

Which results in 102.97977094150823278397990231 417
which is about 103Byte

(The more advanced Analytical Engine would have 20.7kB or 20.2KiB)
sundhaug92 (1 month ago) Show Hide
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No probably not, it isn't a turing machine
sutchsteve (2 months ago) Show Hide
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it doesn't have either bytes or flops - a byte is a group of binary bits, and this machine didn't encode data in binary code. a flop is the number of FLoating-point OPerations, and the difference engine works only with fixed-point numbers.

The actual program, or what would nowadays be called microcode, is in the arrangement of cams which controls the order in which the levers operate on each rotation of the handle, and conceivably you could make the machine do something else by changing them
sundhaug92 (1 month ago) Show Hide
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You can however measure IPS (Instructions Per Second), however both IPS, and FLOPs (if doable) would have been an stupid way of measuring the performance, as you can increase it by increasing the input RPM.
quidproquo2004 (2 months ago) Show Hide
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Buy a curta! It's a handheld mechanical calculator.

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