[General] how to describe time period relationship?(Subset intersection)

[tobysky]

Suppose I have four time periods as follows:

Period A: from July 1st, 2010 to July 10th, 2010,
Period B: from July 3rd, 2010 to July 12th, 2010.
Period C: from July 3rd, 2010 to July 9th, 2010.
Period D: from July 15th, 2010 to July 19th, 2010.

Can I say:

1) Period C is the subset of period A.
2) There is an intersection between period A and B.
3) There is no intersection between period A and D.

or any suggestions on words subset, intersection and union of set?

How to describe time period relationship?

Many thanks.

 

[Rover_KE]

Isn't this a maths question?

Rover

 

[riquecohen]

Isn't this a maths question?

Rover

Yes. Finite Mathematics--vectors, sets, permutations, combinations, etc.

 

[tobysky]

Isn't this a maths question?

Rover

Yes, kind of. But actually, I work in a software company as a developer. I am required to write some design documents. So I just want to check whether I used these words correctly.

Thank you.

 

[Raymott]

1) Period C is a subset of period A. It's not the only subset, so you can't say it's 'the' subset unless you've already mentioned a subset. If the question read, "Identify the subset in the four sentences", you could use 'the'.

2) There is an intersection between period A and B.
3) There is no intersection between period A and D.

or any suggestions on words subset, intersection and union of set?

How to describe time period relationship?

Many thanks.

If your readership was unfamiliar with set theory, you could say:
1. Period A includes all the time in period B.
2. Period A includes some of the time in period B and vice versa.
3. Period A and Period D do not share any time period. / There is no overlap of time periods in Periods A and D.

 

[tobysky]

This is what I want. Thanks for your further answer.