# Using articles when referring to maths objects

Say I want to present a formula for computing a set of even numbers:

S = { x | x is even };

Now, in my research paper I want to tell the readers that they should create such a set for the purpose of further calculations that follow in my algorithm. Which statement is correct from the articles-usage point of view?

(1) Create set S.

(2) Create a set S.

(3) Create an S set.

(4) Create the set S.

(5) Create S.

(6) [other] ... ?

And later on, if I want the reader to, say, remove number 2 from this set, how should I write this?

(1) Remove number 2 from set S.

(2...) [again all the possibilities]

?

## 1 Answer

Good question, maths is* abstract enough that you can have a little leeway:

``````(1) Create set S:
``````

Is correct

``````(2) Create a set S:
``````

Is also correct, but should be continued- "Create a set S, such that ..."

``````(3) Create an S set:
``````

Is incorrect, 'an' is used when the following noun begins with a vowel sound

``````(4) Create the set S:
``````

Could be correct, if the set S has been mentioned before. I wouldn't introduce S to the reader this way.

``````(5) Create S: Same as (4):
``````

Not Incorrect, but I would use (1) or (2)

Basically, when introducing S, I would use `a` or `the`, then once S has been established, drop the article and just call it S.

EDIT: As for discussing elements of the set, I would avoid articles. `Remove 2 from S` sounds cleaner than `Remove 2 from the set S`, and is no more ambiguous.

*As a speaker of Californian English, I don't quite know how to use the term `maths`, we call it `math`. Would you say "Maths are difficult" or "Maths is difficult"?

• What if I want to add also an adjective, say "Create another set S. Remove element 4 from the new set S" ? Jun 19, 2015 at 14:49
• When referring to individual letters, the choice of a or an is determined by pronunciation. The vowels (but not 'y') and 'f', 'h' ,'m' ,'n' ,'r', 's' and 'w' are preceded by "an", since they are pronounced as if they start with a vowel. "F", for instance, is pronounced as if it were spelled "eff". Jun 19, 2015 at 14:55
• Here's my best shot at what I think you're trying to say (the math may be beyond me :D ) `Create a set S, with elements 1, 2, 3, 4. Create a new set with the same elements, T. Remove 4 from T.` So when you duplicate a set, it become a different set, with a different name, while the original set is unchanged. Is this what you mean?
– Will
Jun 19, 2015 at 14:59
• @Will ok. and referring to `S` can I use something like "...with elements from the original set S" ? so that make it explicit "the original set" Jun 19, 2015 at 15:02
• Absolutely. By calling it "the original set" and "S" it really helps to remain unambiguous. Talking about multiple abstract structures can get very confusing.
– Will
Jun 19, 2015 at 15:19