James Bryant Lee,

Handheld calculators & number crunching

log bookThese days people don't need to be able to calculate longhand as handheld calculators have taken the pain out of this process.

Most people have a handheld calculator or one on their mobile phone or computer or even their watch. But in the history of maths this facility is a very, very recent introduction.

The first handheld calculator was developed by Texas Instruments in 1967. It could add, multiply, subtract and divide and its output device was a paper tape. It cost a King's rahandheld calculator, Commodorensom to buy!

At school in the 1960s only logarithmic tables were around (see pic top left) and I remember using them along with a slide rule.

My first handheld calculator, a Commodore SR4148R was for my ONC in 1974/1975 (see right). It cost about £50 (£400 at today's prices). I was still using it for my HNC in 1979 and have it now (2011) and it still works fine.

When I started my Degree in 1980, I bought a Texas Instrument calculator that was recommended by the University. It had very tactile keys that "clicked" when pressed. I still have this one too and it works perfectly well. It's in the palm of my hand on the left pic below.

Texas Instrument handcalculator, 1975Around 1996, I upgraded to a Casio model which was big jump in computing power from my previous calculators. Again, I still have this machine which is working fine although the display can be difficult to read if you look directly down on it. See pic on the right, below.

More recently (2011), I replaced my sturdy Casio with another Casio model Fx-991ES which is the one I currently use. This small handheld machine Casio handheld calculator, circa 1996probably has more computing power than the computer aboard the lunar module that first landed a man on the moon in 1969!

We take number crunching as a normal activity these days particularly with the ubiquitous spread sheets (example Excel) which make calculations so easy-peasy.

In the past "longhand" was the only method to carry out calculations of division or mutiplication and my hero Isaac Newton would often calculate logarithms to 55 places as a way of relaxing! Casio handheld calculator, 2011, Fx-991ES

That really is taking things too far - see below being several of his attemps.

These probably took him the best part of a day to complete and today we can get the same result in seconds from the humble calculator with a speed increase of over 40,000 times!

Now if Isaac Newton had such a machine available to him in 1665 the mind boggles as to what other levels he could have risen to!




Longhand calculation by Isaac Newton, c 1665
Newton's several longhand calculations to 55 places, 1665

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