Sometimes, I want to quantify an adjective to make a statement more precise.
E.g.:
This dataset is large, over 1 GB.
Is that a correct use of a comma? I know I could use parentheses: This dataset is large (over 1 GB). But I prefer to avoid parentheses in some situations.
Yes, the example correctly uses a comma:
This dataset is large, over 1 GB.
This treats “over 1 GB” exactly how parentheses would, as a clarifying phrase without which the sentence remains correct:
This dataset is large.
Indeed, be reluctant to use parentheses because they can draw attention to the least important part of a sentence. An exception to this general rule is in technical writing that includes many details, where a sentence such as the following uses parentheses to highlight numerical information so that the specifics are easier to find later.
The first dataset is large (1.2 GB) compared to the second (0.3 GB).
@NathanTuggy points out that legal writing occasionally uses parentheses redundantly, as in:
This dataset is larger than one gigabyte (1 GB).
This dataset is large, over 1 GB.
It's a correct use of a comma, yes.
I'll add something that's a little jarring about it as a sentence--which is how it might sound out in a person's head--especially if that person doesn't translate "1 GB" to "a gigabyte" automatically in their head.
You wouldn't write the following, but imagine it sounding like: This dataset is large, over one gee bee.
So your sentence could be smoother written as how you'd say it out loud:
Which is something you might prefer. But if you're talking about something larger, like 350 GB, then you'd certainly want to keep it as a number instead of expanding it out to "three-hundred-and-fifty gigabytes" (for instance).
