SortNew (GenericNamedArraylist function): Difference between revisions

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In the <var>SortNew</var> parameter, you identify the sort key function that gets applied to each <var>FloatNamedArraylist</var>, <var>NamedArraylist</var>, or <var>UnicodeNamedArraylist</var> item.
In the <var>SortNew</var> parameter, you identify the sort key function that gets applied to each <var>FloatNamedArraylist</var>, <var>NamedArraylist</var>, or <var>UnicodeNamedArraylist</var> item.
This function must
This function must
operate on that item type and return an <var>[[Intrinsic classes|intrinsic]]</var> datatype (<var>Float</var>, <var>String</var>, <var>Longstring</var>, or <var>Unicode</var>) value. The values returned by the function are sorted into ascending or descending order to determine the position of their associated item in the result <var>Arraylist</var>.
operate on that item type and return an <var>[[Intrinsic classes|intrinsic]]</var> datatype (<var>Float</var>, <var>String</var>, or <var>Unicode</var>) value. The values returned by the function are sorted into ascending or descending order to determine the position of their associated item in the result <var>Arraylist</var>.


==Syntax==
==Syntax==
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==Usage notes==
==Usage notes==
<ul>
<ul>
<li>If the function applied by <var>sortNew</var> returns string values, <var>sortNew</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 uppercase letters, also ranked alphabetically, followed by the numbers; ie: <code>'a'..'z','A'..'Z',0..9</code>.
<li>If the function applied by <var>SortNew</var> returns string values, <var>SortNew</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 uppercase 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>sortNew</var> returns them in the same order in which they appear in the input <var class="term">anyNal</var>.
<li>If two or more <var class="term">anyNal</var> items have equal values after all sort criteria are applied, <var>SortNew</var> returns them in the same order in which they appear in the input <var class="term">anyNal</var>.
<li>The function in the parameter for <var>SortNew</var> is a method value, not a <var class="product">User Language</var> expression.  That is, you cannot provide a function that, itself, also has an argument (say, <code>Char(13)</code>) as the <var>SortNew</var> parameter.
<li>The function in the parameter for <var>SortNew</var> is a method value, not a <var class="product">User Language</var> expression.  That is, you cannot provide a function that, itself, also has an argument (say, <code>Char(13)</code>) as the <var>SortNew</var> parameter.
<li>As of <var class="product">[[Sirius Mods|Sirius Mods]]</var> Version 7.6, the default <var>sortCriteria</var> argument is the <var>SortOrder</var> <code>Ascending(This)</code>, where <code>This</code> is the identity function 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>:sortnew(ascending(this))</code> can be specified simply as <code><var class="term">al</var>:sortnew</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>sortCriteria</var> argument is the <var>SortOrder</var> <code>Ascending(This)</code>, where <code>This</code> is the identity function 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">anyNal</var>:sortNew(ascending(this))</code> can be specified simply as <code><var class="term">anyNal</var>:sortNew</code>.  See the [[SortNew (Arraylist function)#Examples|SortNew example]].
<li><var>SortNew</var> is available in <var class="product">Sirius Mods</var> Version 7.3 and later.
<li><var>SortNew</var> is available in <var class="product">Sirius Mods</var> Version 7.3 and later.
</ul>
</ul>
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Michael Palin  (born: 19430505)
Michael Palin  (born: 19430505)
</p>
</p>
<li>This fragment is a simple <var>SortNew</var> example; the string items are sorted by their values:
<p class="code">%nal is namedArraylist of string len 30       
%nal = new                                     
%nal('Akron') = 'Rubber City'                 
%nal('Atlanta') = 'The Athens of the South'   
%nal('Philadelphia') = 'City of Brotherly love'
%al is arraylist of string len 30             
%al = %nal:sortNew(ascending)                 
%al:print                                     
</p>
The result is:
<p class="output">1: City of Brotherly love   
2: Rubber City               
3: The Athens of the South
</p>
<li>For additional sorting examples, see [[Collections#Finding collection maxima and minima, and sorting|"Finding collection maxima and minima, and sorting"]].</ol>
<li>For additional sorting examples, see [[Collections#Finding collection maxima and minima, and sorting|"Finding collection maxima and minima, and sorting"]].</ol>


==See also==
==See also==
{{Template:GenericNamedArraylist:SortNew footer}}
{{Template:GenericNamedArraylist:SortNew footer}}

Revision as of 21:54, 7 August 2012

Sort items to an Arraylist (FloatNamedArraylist, NamedArraylist, and UnicodeNamedArraylist classes)


SortNew sorts the method object FloatNamedArraylist, NamedArraylist, or UnicodeNamedArraylist and returns the sorted result in a new Arraylist. 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 each FloatNamedArraylist, NamedArraylist, or UnicodeNamedArraylist item). The sort criteria pairs are passed to SortNew as a SortOrder argument.

In the SortNew parameter, you identify the sort key function that gets applied to each FloatNamedArraylist, NamedArraylist, or UnicodeNamedArraylist item. This function must operate on that item type and return an intrinsic datatype (Float, String, 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 result Arraylist.

Syntax

%al = anyNal:SortNew[( [sortOrder])]

Syntax terms

%al An Arraylist object to contain the sorted anyNal items.
anyNal The input FloatNamedArraylist, NamedArraylist, or UnicodeNamedArraylist object.
sortOrder One or more SortOrder objects, which consist of an ordering direction for the sort and a key to sort by, 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 anyNal arrayList. For example:

%alist = %namray:sortnew(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 objects of the type specified on the anyNal 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 SortNew returns string values, SortNew 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 uppercase letters, also ranked alphabetically, followed by the numbers; ie: 'a'..'z','A'..'Z',0..9.
  • If two or more anyNal items have equal values after all sort criteria are applied, SortNew returns them in the same order in which they appear in the input anyNal.
  • The function in the parameter for SortNew is a method value, not a User Language expression. That is, you cannot provide a function that, itself, also has an argument (say, Char(13)) as the SortNew parameter.
  • As of Sirius Mods Version 7.6, the default sortCriteria argument is the SortOrder Ascending(This), where This is the identity function described further in "Using the This function as the Maximum parameter". Therefore, anyNal:sortNew(ascending(this)) can be specified simply as anyNal:sortNew. See the SortNew example.
  • SortNew is available in Sirius Mods Version 7.3 and later.

Examples

  1. The following request displays a NamedArraylist in its normal sorted-by-label order, then in order of a sort based on a Variable member of the user class.

    begin class python public variable firstname is string len 16 variable surname is string len 16 variable birthdate is float constructor newpy (%sname is string len 16, - %name is string len 16, %bd is float) function myPrint is longstring end public constructor newpy (%sname is string len 16, - %name is string len 16, %bd is float) %this:firstname = %name %this:surname = %sname %this:birthdate = %bd end constructor function myPrint is longstring return %this:firstname with ' ' with - %this:surname with ' ' with - '(born: ' with %this:birthdate with ')' end function end class %i is float %lp is Arraylist of object python %nlp is namedArraylist of object python %nlp = new %nlp('Gilliam') = newpy('Gilliam', 'Terry', '19401122') %nlp('Cleese') = newpy('Cleese', 'John', '19391027') %nlp('Idle') = newpy('Idle', 'Eric', '19430329') %nlp('Palin') = newpy('Palin', 'Michael', '19430505') %nlp('Chapman') = newpy('Chapman', 'Graham', '19410108') %nlp('Jones') = newpy('Jones', 'Terry', '19420201') for %i from 1 to %nlp:count print %nlp:itembynumber(%i):myprint end for print '======================================' print 'After the sort by birthdate:' %lp = %nlp:sortnew(ascending(birthdate)) for %i from 1 to %lp:count print %lp(%i):myprint end for end

    The result is:

    Graham Chapman (born: 19410108) John Cleese (born: 19391027) Terry Gilliam (born: 19401122) Eric Idle (born: 19430329) Terry Jones (born: 19420201) Michael Palin (born: 19430505) ====================================== After the sort by birthdate: John Cleese (born: 19391027) Terry Gilliam (born: 19401122) Graham Chapman (born: 19410108) Terry Jones (born: 19420201) Eric Idle (born: 19430329) Michael Palin (born: 19430505)

  2. This fragment is a simple SortNew example; the string items are sorted by their values:

    %nal is namedArraylist of string len 30 %nal = new %nal('Akron') = 'Rubber City' %nal('Atlanta') = 'The Athens of the South' %nal('Philadelphia') = 'City of Brotherly love' %al is arraylist of string len 30 %al = %nal:sortNew(ascending) %al:print

    The result is:

    1: City of Brotherly love 2: Rubber City 3: The Athens of the South

  3. For additional sorting examples, see "Finding collection maxima and minima, and sorting".

See also