Never, in any engineering field, have I EVER seen anyone simplify pi to 5. For that matter, I have never seen anyone simplify to 3. It is always 3.14. I feel like pi simplification is a weird meme that people think engineers do but is never practiced anywhere.
It’s like if there was a meme about chefs saying they always replace eggs with grapefruit. No they don’t, and it’s nonsense to think they do.
The only time you should be doing head calcs as an engineer is to double check that you have a reasonable answer with the actual calcs on your actual calculator.
There’s a lot of weird stereotypes out there that make no sense. Like the whole “programmers wear thigh high socks” thing. Where did that even come from?
There’s less and less reason to do it (and it’s never 5). On systems without floating point you might want to do round it a bit, but only if the specific thing you’re doing allows it, and even then you’re more likely to do a fixed-point approach by using e.g. 314 and dividing by 100 later, or adjusting that value a bit so you can divide by 128 via bitshift if you’re on a chip where division is expensive. However, in 2025 you almost certainly should have picked a chip with an FPU if you’re doing trigonometry.
And while rounding pi to 3 or 4 is certainly just a meme, there are other approximations which are used, like small-angle approximations, where things like sin(x) can be simplified to just x for a sufficiently small x.
Pi is roughly 5.
Never, in any engineering field, have I EVER seen anyone simplify pi to 5. For that matter, I have never seen anyone simplify to 3. It is always 3.14. I feel like pi simplification is a weird meme that people think engineers do but is never practiced anywhere.
It’s like if there was a meme about chefs saying they always replace eggs with grapefruit. No they don’t, and it’s nonsense to think they do.
you’ve never seen anybody simplify it to 3 when doing head calcs without a phone nearby?
it doesn’t happen often, in fact I’ve seen it once. in a decade.
The only time you should be doing head calcs as an engineer is to double check that you have a reasonable answer with the actual calcs on your actual calculator.
For back-of-the-envelope or mental calculations, pi is often 3 or 10^(1/2).
The latter is better than 1% accurate, and has nice properties when doing order-of-magnitude/log space calculations in base 10.
There’s a lot of weird stereotypes out there that make no sense. Like the whole “programmers wear thigh high socks” thing. Where did that even come from?
Bet that one was started by all those dastardly programmers that wear knee high socks!
There’s less and less reason to do it (and it’s never 5). On systems without floating point you might want to do round it a bit, but only if the specific thing you’re doing allows it, and even then you’re more likely to do a fixed-point approach by using e.g. 314 and dividing by 100 later, or adjusting that value a bit so you can divide by 128 via bitshift if you’re on a chip where division is expensive. However, in 2025 you almost certainly should have picked a chip with an FPU if you’re doing trigonometry.
And while rounding pi to 3 or 4 is certainly just a meme, there are other approximations which are used, like small-angle approximations, where things like
sin(x)can be simplified to justxfor a sufficiently smallx.