Difference between revisions of "Table.sort"
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=== Description === | === Description === | ||
Sorts the elements of a table in-place (i.e. alter the table). | Sorts the elements of a table in-place (i.e. alter the table). | ||
− | < | + | <syntaxhighlight lang="lua"> |
table.sort(table,comp) | table.sort(table,comp) | ||
− | </ | + | </syntaxhighlight> |
A comparison function can be provided to customise the element sorting. The comparison function must return a boolean value specifying whether the first argument should be before the second argument in the sequence. The default behaviour is for the < comparison to be made. For example, the following behaves the same as no function being supplied: | A comparison function can be provided to customise the element sorting. The comparison function must return a boolean value specifying whether the first argument should be before the second argument in the sequence. The default behaviour is for the < comparison to be made. For example, the following behaves the same as no function being supplied: | ||
− | + | <syntaxhighlight lang="lua"> | |
− | + | > t = { 3,2,5,1,4 } | |
− | + | > table.sort(t) | |
− | + | > = table.concat(t, ", ") -- display sorted values | |
+ | 1, 2, 3, 4, 5 | ||
+ | </syntaxhighlight> | ||
=== Parameters === | === Parameters === | ||
'''table''': (table) table to sort<br/> | '''table''': (table) table to sort<br/> | ||
'''comp''': (function) comparison function returning bool comparison result '''optional'''<br/> | '''comp''': (function) comparison function returning bool comparison result '''optional'''<br/> | ||
+ | |||
+ | === Examples === | ||
+ | '''Alphabetical order''' | ||
+ | <syntaxhighlight lang="lua"> | ||
+ | local people = {} | ||
+ | people [1] = { name = "bob", age = 26 } | ||
+ | people [2] = { name = "sue", age = 22 } | ||
+ | people [3] = { name = "ann", age = 28 } | ||
+ | table.sort(people, function(a, b) | ||
+ | return a.name < b.name | ||
+ | end) | ||
+ | </syntaxhighlight> | ||
+ | |||
+ | '''Inversed numerical order''' | ||
+ | <syntaxhighlight lang="lua"> | ||
+ | local people = {} | ||
+ | people [1] = { name = "bob", age = 26 } | ||
+ | people [2] = { name = "sue", age = 22 } | ||
+ | people [3] = { name = "ann", age = 28 } | ||
+ | table.sort(people, function(a, b) | ||
+ | return a.age > b.age -- inversed | ||
+ | end) | ||
+ | </syntaxhighlight> | ||
{{Table}} | {{Table}} |
Latest revision as of 16:35, 24 May 2024
Available since: Gideros 2011.6
Class: table
Description
Sorts the elements of a table in-place (i.e. alter the table).
table.sort(table,comp)
A comparison function can be provided to customise the element sorting. The comparison function must return a boolean value specifying whether the first argument should be before the second argument in the sequence. The default behaviour is for the < comparison to be made. For example, the following behaves the same as no function being supplied:
> t = { 3,2,5,1,4 }
> table.sort(t)
> = table.concat(t, ", ") -- display sorted values
1, 2, 3, 4, 5
Parameters
table: (table) table to sort
comp: (function) comparison function returning bool comparison result optional
Examples
Alphabetical order
local people = {}
people [1] = { name = "bob", age = 26 }
people [2] = { name = "sue", age = 22 }
people [3] = { name = "ann", age = 28 }
table.sort(people, function(a, b)
return a.name < b.name
end)
Inversed numerical order
local people = {}
people [1] = { name = "bob", age = 26 }
people [2] = { name = "sue", age = 22 }
people [3] = { name = "ann", age = 28 }
table.sort(people, function(a, b)
return a.age > b.age -- inversed
end)