Humble Pi: When Math Goes Wrong in the Real World

by Matt Parker

As humans, we are not good at judging the size of large numbers.

At 3:14 a.m. on Tuesday, January 19, 2038, many of our modern microprocessors and computers are going to stop working.

So the program initially sets active_ row = 1 to start at the top row and runs this piece of code

while data(row = active_row, column=1) != NULL: active_row = active_row + 1 In a lot of computer languages, != means “not equal to.” So, for each row, it checks if the data in the first cell is

not equal to null. If it’s not equal to null, it adds 1 to the row and keeps going until the first blank row.

For generations, cartographers have been sneaking fictitious places into real maps (often as a way to expose people plagiarizing their work),

phone number?

The rule of thumb should be: if you’re not going to do any math with it, don’t store it as a number.

if we called them “phone digits” instead of “phone numbers,”

You can think of hexadecimal as binary in disguise.

Excel has difficulty keeping track of how many rows are in a spreadsheet.

On the whole, doing any kind of important work in a spreadsheet is not a good idea. They are the perfect environment for mistakes to spawn and grow unchecked.

A spreadsheet has all the outward appearances of making it look as if serious and rigorous calculations have taken place. But they’re only

as trustworthy as the formulas below the surface.

If you look at the classic soccer-ball design, you will find twenty white hexagons and twelve black pentagons.

Getting to space is easy. It’s staying there that’s difficult.

As a general rule, doors should open in the direction they would need to in an emergency.

there needs to be an even number of cogs so that a clockwise

cog meets a counterclockwise one. Any odd number of cogs in a loop will come to a standstill.

Counting from zero is a classic behavior of programmers.

Zero is, after all, a perfectly good number.

Five sections of fence require six posts.

256 is one of the most important numbers in computing.”

Computers just blindly follow the rules they are given and do the logical thing, with no regard for what may be the reasonable thing.

tilt the iPhone sideways so it goes into scientific calculator mode

Because of the limitations of binary, computers are consistently close, but not quite. Like any food product with “diet” in the title, it’s always a bit off.

But the problem with a percentage error is that, as the value gets bigger, the error grows with it.

that the problem was a divide-by-zero error. The mistake seems to have started when someone entered a zero in a database somewhere (and the database treated it as a number, not a null entry).