arithmetic language

[desh]

We say "two plus three", but we say "add two and three", and that's "addition". And some of us might've laughed under our breath in middle school at the kids in math class who used "plus" as a verb. Similarly, "two minus three" but "subtract three from two" for "subtraction", "two times three" but "multiply two by/and three" for "multiplication", and so on.

When you're talking sets, what do you do instead? I guess "B intersect C" and "intersect B and C" for "intersection", but what about union? "Then you union B and C" sounds almost as wrong as "Then you times 2 and 3".

Comments

[leftyjew.livejournal.com]

As a computer programmer, I union B and C. Following your pattern, I guess that's called "unionization" :) OR you can "join B and C" or "take the union of B and C". Of course, this is coming from a job where you take about being stateless and stateful, or use "overscore" to mean "not underscored", or use compareTo, malloc and toString as transitive verbs.

[conana.livejournal.com]

==leftyjew
Although using 'overscore' that way is foul.

[fweebles.livejournal.com]

"Take the union (intersection) of sets A and B".
"Take the complement of set A".

Oh Bachelor of Mathematics, how useful you've become. ;)

[desh]

Can you say that properly in English without the word "take" (or a synonym), though? Because you're using "union" as analogous to "sum", and I'm still wondering if "union" (or something else) is an appropriate English analog of "add".

[leftyjew.livejournal.com]

isn't unioning sets adding them? Or OR'ing them. and intersecting sets is AND'ing or multiplying, right?

[fweebles.livejournal.com]

I don't know if you can in general, but you couldn't in any of my classes without getting ridiculed by the professor, the students, or both. It was pretty much the same reaction that you'd get if you'd said, "when you plus these two numbers together..."

As I see it.

[captainjew.livejournal.com]

The problem is that addition, subtraction, et al. are operations to be performed where as union and intersection are subsets rather than something to do.

Re: As I see it.

[desh]

I disagree. You don't think these are analogous, if not in the sorts of answers they produce, then at least in whether they're "something to do" or not?

a * b = c
A ∩ B = C

or, in a procedural sense:

let c = a * b
let C = A ∩ B

Re: As I see it.

[captainjew.livejournal.com]

But with multiplication you are solving something. Any solutions involving union or intersection are achieved through other operations.

Re: As I see it.

[desh]

I don't know; I definitely feel like I'm solving things. Here, let me give you a fake example from work:

I need to calculate the set of all the people who don't have to pay taxes. The law says that you don't have to pay taxes iff you have a dog and red is your favorite color. I already have the set of all dog owners and the set of all people with a given favorite color. So I want:

No_taxes = Dog_owners ∩ Favorite_color(red)

How is that any different conceptually than this?

Tax_owed = Gross_income - Deductions

[ulicqel.livejournal.com]

god damn your all a bunch of dorks! :-D