Lies, Damn Lies

Calculators

As someone who considers himself a mathematician, or at least a poor excuse for one, I have a slight interest in calculators. Not as huge as a layperson might expect, as you one reaches a point on ones subject where numbers are rarely mentioned, and then only in disdain ("good lord, you don't do actual CALCULATIONS do you?"), but certainly at A-level and in certain degree level subjects, one must deign to deal in hard numbers. I am now thoroughly used to scientific calculators, which obey the basic rules of BODMAS (Brackets, division, multiplication, addition, summation. I don't recall what the O stands for), so it comes as a shock when I need to do a little calculation and find the only tools at hand to be my phone or my computer.

The mobile phone is not designed to be a calculator, although it certainly has the processing power to be one if it wanted to be. Sadly it is designed for people who have never encountered bodmas, which makes doing any calculation fiendishly difficult. Coupled with it's lack of a memory function, it's almost impossibly hard to use the bloody thing. The computer calculator is even worse, because it mockingly claims that it has a scientific mode. This merely means it adds extra buttons, although often not the ones you need, and still does not obey the rules any basic scientific calculator would, rendering it, again, close to useless.

Even scientific calculators hold perils for any degree level mathematicians thanks to the distiniction between log and ln. You see when you are first taught logarithms you are normally introduced to base 10 ie log10(x)=y where 10^y=x so log10=1, for example. For short, you say log x, excluding the little 10 (which should be a subscript but I am too lazy to find out the html to do that). Later on you will be introduced to the number e, a deeply vital number in mathematics, and you will often take logarithms with base e- we call this ln. Except that at degree level you never, ever, ever need to take a logarithm of something at anything other than base e, so you soon get into the habit of calling ln log. Confused yet? You should be. Sadly the habits of many mathematicians differ, which can lead to some confusion along the way.

ANYWAY, after four years of meaning base e when you say log, it becomes ingrained, so when you actually have to do a calculation, you will unthinkingly press the log button, and get your answers consistently wrong. And often you won't even know why......

I apologise if you lost me after the word "As", but sadly this rant had to be written in somewhat technical language. Or at least, I chose to write it that way....

posted by Mr K @ 10:36 pm