I work with polystyrene blocks, I get a list of different sizes

>>1222882
>1220mmX1220mm

God damn metric fucks. Just say 4'

>>1222925
why would anyone want to use some shitty 200 year old world measurement system only used by a tiny fraction of the population?

>>1222932
Dont ask me ask the guy making 1220*1220 stock.

>>1222882
Its called "packing problem" and it has no verified theoretical solution. Googal it and get enlightened

>>1222932
I honestly want to know why it's 1220mm. Why not 122cm, or 12.2dm, or 1.22m. Back in the 70's when I learned this stuff they were all about use the prefix that makes the most sense, that's part of why metric is cool! Why are poor decimeters completely ignored? All I ever see are mm, cm, m, and km. Wtf? And by the way, Anon is right, this is exactly 4 feet. You metric guys realize that a lot of your shit is imperial, like it or not, no matter what you call it, right?

>>1222939
>I honestly want to know why it's 1220mm.

In Australia almost all building is done in mm. Couldn't tell you why but it is very simple only having the one unit. When you say you want something 6348 everyone knows what you mean.

And you are right that much of our building materials come in imperial sizes (920, 1220, 1530,1830, 2130, 2440, 2740 and so on) . Which really makes people sound retarded when they say imperial is better because you can divide it easily.

>>1222942
>when they say imperial is better because you can divide it easily.

who says that? As you say, it is not true.

Metric is better because you never have to convert from feet to inches to yards to miles etc. You just shift the decimal point.

>>1222939
Millimetres is just a standardisation to avoid confusion. Any technical drawing will be marked in mm even if it isn't specifically annotated that way. We use mm instead of a larger measurement because applications that required small measurements would have to be marked as being fractions of anything larger and a whole number is neater.

>>1222936
It does have a theoretical solution, it just takes a lot of time to calculate for big problem inputs (aka many pieces to cut from a single block). For small inputs it shouldn't take that long, most of the times approximations are used to get fast solutions that are close (but not equal) to the optimal one.

>>1222882
If you are fine with approximate solutions you can look for some bin packing 2d solver online

>>1222977
I find it fucking hilarious that when you get to millimeter range and under, the corresponding imperials units are milli-inches.

>>1222939
>You metric guys realize that a lot of your shit is imperial, like it or not, no matter what you call it, right?
Everything has it's base somewhere.
But the thing is that it doesn't matter any more from where it came from after it's converted to SI. That's the beauty of the whole system.

As with the lack of dm, it just isn't used. Usually you use the prefix you need in terms of accuracy. 1220 means that its technically in the mm precision.

>>1222925
>God damn metric fucks. Just say 4'
And when i want to shave off 6mm, what do I call it then? 4 feet-6mm? Or do I recalculate 4' to 1220 (what it supposedly is, won't bother to calculate) and then subtract 6mm?
If you are smart, you start to see the beauty of it...

>>1222942
>>1222977
>>1222987
Thank you Anons. I appreciate the answers.

>>1222936
>no verified theoretical solution
There is a solution: Brute force. It is not a polynomial solution, but it is a solution.

The problem is similar to the Knapsack problem and is NP-complete.

>>1222882
OP, if you can solve this problem, you will be a billionaire.

>>1222983
Thousandths.

>>1223040
mil- the greek or whatever for thousandths or something so yeah, both are the same really.
'mil' is a commonly used term used for thousandths of an inch in some queer engineering circles
leading to some HILARIOUS practical jokes when people specify dimensions as 'mill' as shorthand for 'millimeter' and the part is made to 'mil' instead, wasting thousands in money and time just to teach someone a lesson in being clear and specific in communication.

>>1223041
>a lesson in being clear and specific in communication.

As a fresh out of school engineer I asked the shop foreman to take a tenth off of a crude test fixture so it would fit in an opening; the object was about 6 inches wide so I was referring to a tenth of an inch, or so I assumed.

He goes "A FUCKING TENTH???"

And that was when I learned that a "tenth" was understood to be a tenth of one thousandth, or 0.0001 inches.

>>1223055
Having worked in a dozen shops over my life, the first thing you learn is that the lingo is different everywhere and standardization of practices is a myth.

>>1222936
Calculating an **exact** solution takes too much time, but there are tons of heuristic solutions that are >95% optimal and can be calculated on the fly.

OP I don't have much to add but I will say that the sawmill across the road is running a version of this software to cut dimensional lumber out of logs, that might expand your search criteria.

>>1223055
i would have taken off 1/10 of of the overall 6 inches (1/6") just to be a dick.

File: 20170807_090224.jpg (4MB, 4032x3024px) Image search: [Google]

4MB, 4032x3024px

Op this is something like what i get. I highlight where to set our wires to width. And the colum with symbols are height. First longer size colum get docked with guilitine. We get alot of stock blocks also so some auto calcukation worked off diferent size blocks would make this task so much more efficent

>>1223104
>1/10 of of the overall 6 inches (1/6")
lmao

>>1223566
>>1/10 of of the overall 6 inches (1/6")

maybe I'm missing the jokeage here, but 6/10 is 0.6 while 1/6 is 0.167.

>>1222925
TOPKEK

>>1222932
Because MERICA

>>1222935
You anons are probably getting raped. Just buy new polystyrene and build a big ass steam box. You could have any size and shape u want to cut up.

Sell the waste to a beanbag factory or somthing. Shread the waste back down and sell it as fill material?

>>1222983
K>the more u know

>>1223585
Guess its a good thing they don't let me work with fractions. Boy is my face red.