Re: [Haskell-cafe] Difference between div and /

On Tuesday 01 June 2010 22:40:51, Jonas Almström Duregård wrote:

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One might expect a == (a/b)*b and other common arithmetic formulas to hold for division?

Better not if one's using Float or Double.

I figured someone would say that :)

*g*

What about this one: round (a/b/c) == round (a/(b*c))

Don't know, we have (a `quot` b) `quot` c == a `quot` (b*c) for Integers (overflow may or may not break that for Int), so if (/) were truncating division for Integral types, we'd have that. I like the distinction between (/) and div (and quot), but I have no problem using (/) for integer division in Python, C, Java or C#.

Of course this doesn't work on Integers...

/J

On 1 June 2010 21:08, Daniel Fischer wrote:

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On Tuesday 01 June 2010 20:26:55, Jonas Almström Duregård wrote:

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One might expect a == (a/b)*b and other common arithmetic formulas to hold for division?

/Jonas

Better not if one's using Float or Double.