Sort (Arraylist subroutine): Difference between revisions

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<li>If the function applied by <var>Sort</var> returns string values, <var>Sort</var> uses the decimal-equivalent value of the character bytes to determine the ascending or descending alphabetic order of the associated <var class="term">al</var> items.  Lowercase letters are first ranked alphabetically, then upper case letters, also ranked alphabetically, followed by the numbers; ie: <code>'a'..'z','A'..'Z',0..9</code>.
<li>If the function applied by <var>Sort</var> returns string values, <var>Sort</var> uses the decimal-equivalent value of the character bytes to determine the ascending or descending alphabetic order of the associated <var class="term">al</var> items.  Lowercase letters are first ranked alphabetically, then upper case letters, also ranked alphabetically, followed by the numbers; ie: <code>'a'..'z','A'..'Z',0..9</code>.
<li>If two or more <var class="term">al</var> items have equal values after all sort criteria are applied, <var>Sort</var> places them in the same order in which they appear in the input <var class="term">al</var>.
<li>If two or more <var class="term">al</var> items have equal values after all sort criteria are applied, <var>Sort</var> places them in the same order in which they appear in the input <var class="term">al</var>.
<li>The function in the parameter for <var>Sort</var> is a method value, not a User Language expression.  That is, you cannot provide a function that itself has an argument (say, <code><var>[[ToIntegerPower and ToPower (Float functions)|ToIntegerPower]]</var>(2)</code>) as the <var>Sort</var> parameter.
<li>The function in the parameter for <var>Sort</var> is a method value, not a <var class="product">User Language</var> expression.  That is, you cannot provide a function that itself has an argument (say, <code><var>[[ToIntegerPower and ToPower (Float functions)|ToIntegerPower]]</var>(2)</code>) as the <var>Sort</var> parameter.
<li>As of <var class="product">[[Sirius Mods|Sirius Mods]]</var> Version 7.6, the default <var class="term">sortOrder</var> argument is the <var>sortOrder</var> <code>Ascending(This)</code>, where <var>This</var> is the identity function value described further in [[Collections#Using the This function as the Maximum parameter|"Using the This function as the Maximum parameter"]].  Therefore, <code><var class="term">al</var>:sort(ascending(this))</code> can be specified simply as <code><var class="term">al</var>:sort</code>.  See the [[SortNew (Arraylist function)#Examples|"SortNew example"]].
<li>As of <var class="product">[[Sirius Mods|Sirius Mods]]</var> Version 7.6, the default <var class="term">sortOrder</var> argument is the <var>sortOrder</var> <code>Ascending(This)</code>, where <var>This</var> is the identity function value described further in [[Collections#Using the This function as the Maximum parameter|"Using the This function as the Maximum parameter"]].  Therefore, <code><var class="term">al</var>:sort(ascending(this))</code> can be specified simply as <code><var class="term">al</var>:sort</code>.  See the [[SortNew (Arraylist function)#Examples|"SortNew example"]].
  <li><var>Sort</var> is available in <var class="product">[[Sirius Mods|Sirius Mods]]</var> Version 7.3 and later.
  <li><var>Sort</var> is available in <var class="product">[[Sirius Mods|Sirius Mods]]</var> Version 7.3 and later.

Revision as of 18:44, 19 March 2012

Sort the input Arraylist (Arraylist class)

Sort sorts the method object Arraylist replacing it with the sorted result. The sort is based on one or more sort criteria, each of which consists of a sorting direction (ascending or descending) paired with a sort key (a function that gets applied to an Arraylist item). The sort criteria pairs are passed to SortNew as a SortOrder argument.

Each sort key function (which is applied to the Arraylist items) must operate on the item type and return an intrinsic datatype (Float, String, Longstring, or Unicode) value. The values returned by the function are sorted into ascending or descending order to determine the position of their associated item in the Arraylist.

Syntax

al:Sort[( [sortOrder])]

Syntax terms

al The input Arraylist object.
sortOrder One or more SortOrder objects, which consist of an ordering direction for the sort and an attribute, or key, to sort by. The ordering direction and sort key are specified in the form: order(key). The order is either Ascending or Descending, and the key is a function that is applied to each item in the al. The values returned by the function are sorted into ascending or descending order to determine the position of their associated item in the rearranged al. For example:

al:sort(descending(length))

The function is a method value (a method or class member name literal, or a method variable) for a method that operates on items of the type specified on the al declaration and that returns a numeric or string value. This is described further in "Specifying a SortOrder's sort key method".

Usage notes

  • If the function applied by Sort returns string values, Sort uses the decimal-equivalent value of the character bytes to determine the ascending or descending alphabetic order of the associated al items. Lowercase letters are first ranked alphabetically, then upper case letters, also ranked alphabetically, followed by the numbers; ie: 'a'..'z','A'..'Z',0..9.
  • If two or more al items have equal values after all sort criteria are applied, Sort places them in the same order in which they appear in the input al.
  • The function in the parameter for Sort is a method value, not a User Language expression. That is, you cannot provide a function that itself has an argument (say, ToIntegerPower(2)) as the Sort parameter.
  • As of Sirius Mods Version 7.6, the default sortOrder argument is the sortOrder Ascending(This), where This is the identity function value described further in "Using the This function as the Maximum parameter". Therefore, al:sort(ascending(this)) can be specified simply as al:sort. See the "SortNew example".
  • Sort is available in Sirius Mods Version 7.3 and later.

Examples

For examples of the Sort method, see "Finding collection maxima and minima, and sorting".

See also

  • SortNew which works like Sort but returns a new Arraylist instead of replacing the method object.