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Is it good style to write $0, $0, $0 as $0?

The following does not seem so clear:

$0

as it may be interpreted as: $0 and $ j<1$ or $0, $0

  • 0
    Yes, that’s fine.2012-06-25
  • 0
    In my opinion yes2012-06-25
  • 0
    I assume there is no order among $i$, $j$ and $k$.2012-06-25
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    Another option is $i,j,k \in ]0,1[$ (or $i,j,k \in (0,1)$) depending on how you prefer to write open intervals.2012-06-25
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    If there is danger of it being misunderstood, then you can state early on that when you write "$0\lt i,j\lt 1$" etc. you mean that *each* of $i$ and $j$ lies between $0$ and $1$.2012-06-25
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    Don't be afraid of words in mathematical writing. Example: "$i$, $j$, and $k$ lie in the open interval $(0, 1)$."2014-11-19

3 Answers 3

1

It depends on context.

Let $0\le a$, $b\le 0$ and $c = a - b$. Then $0\le c$.

You can use an interval instead: $i,j,k\in (0,1)$.

4

It is okay. The comma indicates that there is no necessary relation between $i,j$ and $k$.

4

I would definitely interpret $$0 < i,j < 1$$ as $$0 < i < 1 \text{ and } 0 < j < 1. \quad (*)$$ I would not interpret it as $$0 < i \text{ and } j < 1. \quad (**)$$ It is conventional, when writing a single inequality between a variable and a constant, to put the variable on the left, so if I meant (**), I would write $$i > 0,\, j < 1.$$

  • 3
    I think you meant $j \lt 1$ (or maybe $1 \gt j$ to avoid confusion) in $(\ast\ast)$ and afterwards.2012-06-25
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    @t.b.: Fixed. I thought something didn't seem quite right.2012-06-25