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| -rw-r--r-- | docs/spec/system.html | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/docs/spec/system.html b/docs/spec/system.html index a7c1efab..f9839980 100644 --- a/docs/spec/system.html +++ b/docs/spec/system.html @@ -497,7 +497,7 @@ </tr> </tbody> </table> -<p>For each of these functions, <code><span class='Value'>𝕩</span></code> is a natural number. For <code><span class='Function'>Range</span></code>, <code><span class='Value'>𝕨</span></code> must be a valid shape if given, and for <code><span class='Function'>Deal</span></code> and <code><span class='Function'>Subset</span></code> it's a natural number less than or equal to <code><span class='Value'>𝕩</span></code>. All selections are made uniformly at random, that is, each possible result is equally likely. A simple random sample (SRS) of <code><span class='Value'>k</span></code> elements from list <code><span class='Value'>s</span></code> is a list of <code><span class='Value'>k</span></code> distinct elements of <code><span class='Value'>s</span></code> in any order. Both the choice of elements and their ordering must be uniformly random. <a href="../implementation/primitive/random.html#simple-random-sample">Recommended algorithms</a> for SRS selection are variants of a partial Knuth shuffle.</p> +<p>For each of these functions, <code><span class='Value'>𝕩</span></code> is a natural number. For <code><span class='Function'>Range</span></code>, <code><span class='Value'>𝕨</span></code> must be a valid shape (natural number, or list or unit array of natural numbers) if given, and for <code><span class='Function'>Deal</span></code> and <code><span class='Function'>Subset</span></code> it's a natural number less than or equal to <code><span class='Value'>𝕩</span></code>. All selections are made uniformly at random, that is, each possible result is equally likely. A simple random sample (SRS) of <code><span class='Value'>k</span></code> elements from list <code><span class='Value'>s</span></code> is a list of <code><span class='Value'>k</span></code> distinct elements of <code><span class='Value'>s</span></code> in any order. Both the choice of elements and their ordering must be uniformly random. <a href="../implementation/primitive/random.html#simple-random-sample">Recommended algorithms</a> for SRS selection are variants of a partial Knuth shuffle.</p> <p>When <code><span class='Value'>𝕨</span></code> isn't given, <code><span class='Function'>Deal</span></code>'s result contains all elements of <code><span class='Function'>↕</span><span class='Value'>𝕩</span></code>, making it a random shuffle of those values, or random permutation. In <code><span class='Function'>Subset</span></code>, a random choice is made uniformly from the <code><span class='Number'>2</span><span class='Function'>⋆</span><span class='Value'>𝕩</span></code> subsets of <code><span class='Function'>↕</span><span class='Value'>𝕩</span></code>, so that a subset of any length may be returned.</p> <p>In <code><span class='Function'>Range</span></code>, <code><span class='Value'>𝕩</span></code> may be <code><span class='Number'>0</span></code>. In this case the result consists of floating-point numbers in the unit interval from 0 to 1. The numbers should have an overall uniform distribution, but their precision and whether the endpoints 0 and 1 are possible may depend on the implementation.</p> <p>Ranges up to <code><span class='Number'>2</span><span class='Function'>⋆</span><span class='Number'>32</span></code> must be supported (that is, a maximum integer result of <code><span class='Paren'>(</span><span class='Number'>2</span><span class='Function'>⋆</span><span class='Number'>32</span><span class='Paren'>)</span><span class='Function'>-</span><span class='Number'>1</span></code>) if the number system accommodates it. In implementations based on double-precision floats it's preferable but not required to support ranges up to <code><span class='Number'>2</span><span class='Function'>⋆</span><span class='Number'>53</span></code>.</p> |