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remove random floats, better docs

db4
Doug Coleman 2008-10-05 15:14:05 -05:00
parent 7dc7790362
commit fad3d52bc1
2 changed files with 17 additions and 7 deletions
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19
basis/random/random-docs.factor
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@ -16,8 +16,21 @@ HELP: random-bytes*
HELP: random
{ $values { "obj" object } { "elt" "a random element" } }
{ $description "Outputs a random element of the input object. If the object is an integer, an input of zero always returns a zero, a negative integer throws an error, and positive integers yield a random integer in the interval " { $snippet "[0,n)" } ". On a sequence, an empty sequence always outputs " { $link f } " while any other sequence outputs a random element." }
{ $notes "Since integers are sequences, passing an integer " { $snippet "n" } " yields a random integer in the interval " { $snippet "[0,n)" } "." } ;
{ $description "Outputs a random element of the input object. If the object is an integer, an input of zero always returns a zero, while any other integer integers yield a random integer in the interval between itself and zero, inclusive of zero. On a sequence, an empty sequence always outputs " { $link f } "." }
{ $examples
{ $unchecked-example "USING: random prettyprint ;"
"10 random ."
"3" }
{ $example "USING: random prettyprint ;"
"0 random ."
"0" }
{ $unchecked-example "USING: random prettyprint ;"
"-10 random ."
"-8" }
{ $unchecked-example "USING: random prettyprint ;"
"{ \"a\" \"b\" \"c\" } random ."
"\"a\"" }
} ;
HELP: random-bytes
{ $values { "n" "an integer" } { "byte-array" "a random integer" } }
@ -51,7 +64,7 @@ HELP: delete-random
{ $values
{ "seq" sequence }
{ "elt" object } }
{ $description "Delete a random number from a sequence using " { $link delete-nth } " and returns the deleted object." } ;
{ $description "Deletes a random number from a sequence using " { $link delete-nth } " and returns the deleted object." } ;
ARTICLE: "random-protocol" "Random protocol"
"A random number generator must implement one of these two words:"

5
basis/random/random.factor
View File

@ -55,13 +55,10 @@ ERROR: negative-random n ;
M: integer random ( integer -- integer' )
{
{ [ dup 0 = ] [ ] }
{ [ dup 0 < ] [ negative-random ] }
{ [ dup 0 < ] [ neg random-integer neg ] }
[ random-integer ]
} cond ;
M: float random ( float -- elt )
64 random-bits 64 2^ 1- / * ;
: delete-random ( seq -- elt )
[ length random-integer ] keep [ nth ] 2keep delete-nth ;