Help:Sorting

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Template:H:h Tables can be made Template:Mlw via client-side JavaScript with class="sortable". This works in MediaWiki 1.9 and above, which is installed in all Wikimedia projects.

A sortable table is identified by the arrows in each of its header cells. Clicking them will cause the table rows to sort based on the selected column, in ascending order first, and subsequently toggling between ascending and descending order. Links and other wiki-markup are not possible in headers.

Note that all of the below is subject to change due to improvements in the script.

Contents

[edit] JavaScript

The JavaScript code wikibits.js has on each site a copy at {{SERVER}}/skins-1.5/common/wikibits.js, on this site http://en.qi-hardware.com/skins-1.5/common/wikibits.js. In addition a site may have a page MediaWiki:Common.js which adds and overrides some code.

[edit] Sort modes

The way items are sorted depends on the data type of the item currently in the first row. To determine the data type, the following tests are made in order, until one matches. Thus, if "24-12-2007" is the first item, then all items will be compared as dates.

To force an item to match as text, use the "sms" template, e.g. {{sms|101 Dalmatians}}

Tags such as span or sup are ignored when determining data type.

  1. date (see also below)
    • criterion: the first non-blank element is of the form "dd-dd-dddd", "dd-dd-dd", or "dd aaa dddd"
    • order: if wgContentLanguage != "en" then string abcdefghij of length 10 is positioned as ghijdeab, the string abcdefghijk of length 8 as 19ghdeab if gh>=50 (string comparison) and 20ghdeab otherwise (i.e., the assumed format is DD-MM-YYYY or DD-MM-YY), and the string "dd aaa dddd" with aaa an abbreviated month name: chronologically
  2. "currency" (this mode can be useful for other data also)
    • criterion: the first non-blank element starts with $, £, €, or ¥
    • order: numeric, ignoring these symbols and all ordinary letters and commas, but not spaces; note that scientific notation cannot be used, as e and E are removed
  3. numeric
    • criterion: the first non-blank element consists of just digits, points, commas, spaces, "+", "-", possibly followed by "e" or "E" and a string consisting of "+", "-", digits
    • order: if the string starts with a number (where spaces and nbsp's at the start are ignored) the order is numeric according to the first number in the string (parseFloat is applied) after removing the commas, if any; if it does not (parseFloat returns NaN), the element is positioned like 0
    proposed internationalisation: in German etc., treat comma as a decimal point
  4. text (default)
    • criterion: all other cases; to avoid one of the other modes, start e.g. with a hidden "&"; this can be done conveniently with Template:Tim, which also allows more hidden text, as sortkey; while the similar templates above are called at the end of a table element, call this one at the start
    • order: after conversion of capitals to lowercase the order is ASCII - partial list showing the order: !"#$%&'()*+,-./09:;<=>?@[\]^_'az{|}~é— (see also below; a blank space comes before every other character; an nbsp code counts as a space; two adjacent ordinary blank spaces count as one; for multiple blank spaces one can use nbsps or alternate nbsps and ordinary blank spaces)

After sorting, the data type may change, since there is a new item in the first row. This can lead to a cycle of four or even more instead of two. As this is confusing, try and avoid this situation by making sure that every element matches the criterion for the required data type. Using a Template:Ml helps.

An alternative method of making sure the sort mode of each column is as desired, is creating a first row that determines the sort modes, but in such a way that this row is not displayed and is excluded from sorting, see below.

[edit] Examples

Text after a number (e.g. a footnote) does not affect the sorting order, if the sorting mode is numeric. However, if the number at the top has text after it, this makes the sorting mode alphabetic.

numbers
4.0
192
123,456.789
123,456,789
2,500,000,000
300,000,000
3,000,000 abc
5,000,000
2,000 def
-4,000
aaa
-9,999
4,000
9,999
800,000
900,000
numbers
123 564,589.7e12
9
-80
80 abc 5
abc 80
70
600
first alphabetic, later also numeric mode
123.4 ghi
2,500,000,000
300,000,000
3,000,000 abc
5,000,000
2,000 def
4,000
9,999
800,000
900,000
currencies
$ 9
$ 80
$ 70
$ 600
currencies
€ 9
€ 80
€ 70
€ 600
currencies
£ 9
£ 80
£ 70
£ 600
currencies
¥ 9
¥ 80
¥ 70
¥ 600
comparison
a 9
a 80
a 70
a 600
comparison
e 9
e 80
e 70
e 600

The example with "a" gives alphabetic sorting; that with "e" ditto, the data are not mistaken for numbers in scientific format.

mixed notations
1.4285714285714E+17
1000000000000000000
-1000000000000000000
.0000000000000000001
-.0000000000000000001
-1.4285714285714E+17
1.4285714285714E-13
-1.4285714285714E-13
89 123 456 788
89,123,456,789
333
1e10
e 9
e 80
e 70
e 600
999e9
88e80
7e270
999e-9
88e-80
7e-270
-999e9
−999e9
-88e80
-7e270
-999e-9
-88e-80
-7e-270
e3
-e3
1e3
e9
e80
e270
6e11
8e11
first number in each element counts
7-4
2
4
22/7
111
percentage
7%
2
4
22
111
mixed notations
14
-14
11
-12 (retrograde)
12 or 13
12 (?)
ca. 12
12 (approx.)
?

The first example demonstrates that text is positioned at zero, and that e.g. e3 for 1000 is not allowed; use 1e3 instead. It also shows that "-" should be used, not "−".

The second example shows that expressions are not sorted according to their evaluated value, but according to the first number.

The third example shows that a percentage is accepted for numeric sorting mode, but ignored in the actual sorting, so if a column contains percentages, all numbers have to be written as a percentage.

The fourth example shows again that "ca. 12" sorts at 0, as opposed to 12 with some text after it, which sorts at 12. In case such an element arrives at the top of a column, it causes alphabetic sorting mode.

[edit] Additional features

[edit] Excluding the last row from sorting

Sometimes it is helpful to exclude the last row of a table from the sorting process.

This can be achieved using class="sortbottom" on the desired table row (line starting with |-).

Wiki markup

{|class="wikitable sortable"
!Name!!Surname!!Height
|-
|John||Smith||1.85
|-
|Ron||Ray||1.89
|-
|Mario||Bianchi||1.72
|-class="sortbottom"
|||Average:||1.82
|}

What it looks like in your browser

Name Surname Height
John Smith 1.85
Ron Ray 1.89
Mario Bianchi 1.72
Average: 1.82

More generally, one or more lines at the bottom marked with class="sortbottom" are sorted among themselves, but stay at the bottom. Thus it is not possible to keep multiple lines fixed at the bottom:

Using more than one "sortbottom", failing to keep these lines fixed
Name Surname Height
John Smith 1.85
Ron Ray 1.89
Average: 1.82
Name Surname Height

[edit] Excluding the first row from sorting

As follows from what was mentioned above, the first row of a table can be made non-sortable (the code class="sorttop" not being valid) by marking every other row except the first with class="sortbottom". This first row can either be a normal visible row (to provide annotation for the headers) or a hidden row (with each element marked with <span style="display:none">...</span>) to ensure that each column has the desired sort mode.

[edit] Making a column unsortable

If you want a specific column not to be sortable, specify class="unsortable" in the attributes of its header cell.

Wiki markup

{|class="wikitable sortable"
!Numbers!!Alphabet!!Dates!!Currency!!class="unsortable"|Unsortable
|-
|1||Z||02-02-2004||5.00||This
|-
|2||y||13-apr-2005||||Column
|-
|3||X||17.aug.2006||6.50||Is
|-
|4||w||01.Jan.2005||4.20||Unsortable
|-
|5||V||05/12/2006||7.15||See?
|-class="sortbottom"
!Total: 15!!!!!!Total: 29.55!!
|-
|}

What it looks like in your browser

Numbers Alphabet Dates Currency Unsortable
1 Z 02-02-2004 5.00 This
2 y 13-apr-2005 Column
3 X 17.aug.2006 6.50 Is
4 w 01.Jan.2005 4.20 Unsortable
5 V 05/12/2006 7.15 See?
Total: 15 Total: 29.55 Original example

[edit] Striping

The JavaScript that makes tables sortable adds .odd and .even classes to the rows of the resulting table. If a cascading style sheet specifies that text be displayed differently in these two classes, alternating rows in the resulting table will appear differently. For example, including the following code in a style sheet causes every sortable table to have silver and gold background stripes:

tr.odd {
  background-color: silver;
}
tr.even {
  background-color: gold;
}

It is also possible to define an id in a CSS that causes only tables with that id to be striped, for example:

#stripe tr.odd {
  background-color: silver;
}
#stripe tr.even {
  background-color: gold;
}

In this case, only tables with class="sortable" and id="stripe" would display with alternating row colors.

If a user sorts the table according to a different column, the stripes still alternate. I.e., the stripes are specific to the positions of the rows in the sorted table, not to the positions of the rows in the wikitext.

[edit] Sorting with hidden sortkey

If necessary one can apply sorting using a sortkey which due to CSS is not displayed:

<span style="display:none">...</span>

Example:

p<span style="display:none">q</span>r gives pqr

(However, on some projects, notably Ontoworld, a page with this wikitext cannot be saved, as spam protection.)

Javascript sorting is based on the text inside and outside the tags, without the tags themselves. A hidden sortkey can be put at the start. Both in the case of alphabetic and that of numeric sorting the first parts determine the order. Both parts together are used to determine the sort mode, so for numeric sorting the whole should be a valid number.

[edit] Alphabetic sorting with hidden sortkey

The sortkey comes at the start and is separated from the displayed text in such a way that the latter does not affect the sorting order. For example, if a sortkey system is used where there are no blank spaces in any sortkey, then a blank space can be used for separation. If a single blank space is possible in a sortkey, two nbsps can be used. For table elements for which the text to be displayed is equal to the sortkey, no duplication is needed, of course.

If the text inside and outside the tags together is of a form that would cause a sorting mode other than alphabetic (if and when the element is at the top), a character can be appended at the end of the sortkey to avoid this, again making sure it does not affect the sorting order by putting a space or two nbsps. This can be dispensed with if the element can never be at the top, but this can be complicated to assess as that can be caused by sorting other columns, with varying sorting modes, and it can change when deleting a row, adding a column, etc.

Instead of "display=none" another way is using a font color equal to the background, e.g. <font color="#f9f9f9">999</font> gives "999". With this method the hidden code can be seen in selected text (e.g. with the mouse). Also the hidden text is included when copying the rendered text. The first may be an advantage or a disadvantage, the second seems only a disadvantage. A complication is also that if a user uses a background color different from the default, the specified text color may not match it; to make sure they are the same the background color can be specified also.

[edit] Unsuitability of padding with no-break spaces

The effect of left-padding with "&nbsp;" codes, which render as blank spaces, depends on the browser: in IE they are (unlike actual blank spaces) counted for sorting as leading blank spaces, so in a list of numbers with text (for which the alphabetic sorting mode applies) they could be used to equalize the number of characters before the explicit or implicit decimal separator. However, in Firefox they are ignored for the purpose of sorting.

Sorting using nbsps, works on IE but not on Firefox Name
100.3 FM Third
 89.5 FM First
107.3 FM Fourth
 95.3 FM Second

See also w:Talk:List_of_U.S._states_by_population#Sortable_Table.

[edit] Padding with zeros

Example:

  • 000156

Formatnum can be combined with padleft:

Integer:

{{formatnum:{{padleft:299792458|16|0}}}} gives:

  • 0,000,000,299,792,458

Real:

{{formatnum:{{padleft:{{#expr:((299792458.056 - .5) round 0)}}|16|0}}}}.{{padleft:{{#expr:(1000000*(299792458.056 - ((299792458.056 - .5) round 0))) round 0}}|6|0}} gives:

  • 0,000,000,299,792,458.056000

[edit] Alphabetic sortkey for numeric sorting

If one needs to use alphabetic sort mode for numbers, one can construct a hidden alphabetic sortkey for this purpose. To make sure that alphabetic sort mode is used no code should satisfy the criterion for numeric sorting mode. Although this matters only for the element at the top, any element might arrive at the top due to sorting another column. Alphabetic sort mode can for example be achieved by starting all sortkeys with "&". It prevents numbers with a remark, or texts like N/A to affect sorting, and allows any choice for their sortkeys.

In the case of non-negative numbers with known upper limit (i.e., even if the table may need editing in the future the numbers are expected to remain below this limit) the sortkey can be "&" followed by the number with leading zeros. For example, in a table column with non-negative numbers below 1,000,000 the sort key of 23.4 is &000023.4

[edit] General case

To allow a wide range numbers (between -1e100 and 1e100) the following system can for example be used:

  • where scientific notation is used, it is normalized such that the absolute value of the mantissa is between 1 and 10; the exponent is put first
  • scientific notation is used for all negative numbers, and all positive numbers outside some interval (below: 1e-9 to 1e9), and not inside that interval
  • where the absolute value of the exponent and/or the mantissa is a decreasing function of the number, the notation uses its complement with respect to 99 for exponents and 10 for mantissas; the code "c" is added in these cases
  • numbers 0 ≤ x < 1000 get a "+" in front
  • positive numbers in scientific notation with a negative exponent get "+0" in front
  • spaces inside the code and &-signs in front are added where needed:
    • for numbers not in scientific notation the positions of all explicit and implicit decimal points are aligned
    • for the starting position, i.e. the position of the first "-", "+", or "e", of other numbers, see the example table
    • to avoid numeric sorting mode, below we have always either an ampersand or two letters e

In the following the left column shows the code for alphabetic sorting, where cryptic followed by the regular notation. The second column contains the same (hence sorting the same), but with code hidden with CSS. The third column does not contain hidden parts and uses numeric sort mode. When sorting the first or second column "more than 1e9" is positioned suitably, while when sorting the third column it is positioned like 0. Moreover, if this cell would be at the top alphabetic sort mode would be used.

full code for alphabetic sorting display form plain number
Template:Lsc11amp Template:Lsc11amp 6
Template:Lsc11amp Template:Lsc11amp 7
Template:Lsc11amp Template:Lsc11amp 1,048,576
Template:Lsc11amp Template:Lsc11amp 1,234
Template:Lsc11amp Template:Lsc11amp 123
Template:Lsc11amp Template:Lsc11amp 16,777,216
Template:Lsc11amp Template:Lsc11amp 65,536
Template:Lsc11amp Template:Lsc11amp 67,108,864
e23 6 6e23 e23 6 6e23 6e23
e09 1.01 more than 1e9 e09 1.01 more than 1e9 more than 1e9
e09 1 1e9 e09 1 1e9 1e9
&&&&&&&&&+0 ec89 9.999,99 9.999,99e-10 Template:Sms 9.999,99e-10 9.999,99e-10
&&&&&&&&&+0.000,000,001 &&&&&&&&&+0.000,000,001 0.000,000,001
&&&&&&&&&+0 ec87 6 6e-12 &&&&&&&&&+0 ec87 6 6e-12 6e-12
&&&&&&&&&+0 ec86 7 7e-13 &&&&&&&&&+0 ec86 7 7e-13 7e-13
&&&&&&&&&+0 ec87 5 5e-12 &&&&&&&&&+0 ec87 5 5e-12 5e-12
&&&&&&&&&&-e-10 c0.000,01 -9.999,99e-10 &&&&&&&&&&-e-10 c0.000,01 -9.999,99e-10 -9.999,99e-10
&&&&&&&&&&-e-08 c6.8 -3.2e-8 &&&&&&&&&&-e-08 c6.8 -3.2e-8 -3.2e-8
&&&&&&&&&&&-ec86 c0.3 -9.7e13 &&&&&&&&&&&-ec86 c0.3 -9.7e13 -9.7e13
&&&&&&&&&&&-ec99 c7.7 -2.3 &&&&&&&&&&&-ec99 c7.7 -2.3 -2.3
Template:Lsc11amp Template:Lsc11amp 0
Template:Lsc11amp.3 Template:Lsc11amp.3 0.3

[edit] Dates

Date sort mode
07 Apr 2007
16 Apr 2007
16 Mar 2007
05-04-2007
04-05-2007
18 Mar 2007
27 Mar 2007
20 Aug 2006
22 Jul 2006


Date sort mode, sorting works for no preference and preference dmy
07 Apr 2007
00 Jan 2007
00 Mar 2007
16 Apr 2007
28 Feb 2007
28 Feb 2007
28 Jan 2007
28 Jan 2007
07 Apr 2007
16 Apr 2007
1 Mar 2007
01 Mar 2007
27 Mar 2007
20 Aug 2006
22 Jul 2006
1 Mar 2007
01 Mar 2007
27 Mar 2007
20 Aug 2006
22 Jul 2006
String sort mode (edit to view source)
date
2006 a
Template:Dts1
Template:Dts1
2006-12 December 2006
!9936-04 April 64 BC
!9900-07-13-0099-07-13
!9937-09-23-0062-09-23
!9937-10-08-0062-10-08
!9998-12-21-0001-12-21
Template:Dts1
Template:Dts1
Template:Dts1

The sort mode is based on the rendered format; in the case of links: the labels, not the targets (though including any content hidden by "display:none").

Date sort mode:

One of the formats allowed for the date sort mode is produced by the Mediawiki's date-formatting feature in the right combination of preference and wikitext format: we need to use in the wikitext the format [[dd mmm]] [[yyyy]] (done in the example) and either no preference or preference dmy, or use with preference dmy one of the formats [[mmm dd]][[yyyy]], [[yyyy]][[mmm dd]], or [[yyyy]][[dd mmm]].

Incomplete dates:

  • <span style="display:none">00 Jan </span>2007
  • <span style="display:none">00</span> Mar 2007

String sort mode:

String sort mode provides chronological sorting for dates formated as <span style="display:none">&</span>YYYY-MM-DD; the hidden "&" avoids numeric sort mode.

Also we can hide the YYYY-MM-DD and put after that any choice of displayable text, including Mediawiki date formatting. The Wikipedia template Template:Tiw provides a convenient way of applying this method while using the date-formatting feature for display.

For years BC we can use, for example, !9937-09-23 for -0062-09-23 (subtract the year number BC from 10000, or the absolute value of the astronomical year from 9999).

If a table column contains any or all incomplete dates, this will not cause sorting problems. If only a year and month are given, that incomplete date is positioned alphabetically before the first day of the month in question. Likewise, if only a year is given, the date is positioned before the first month or day given for that year.

If at some point (i.e., after possible previous sorting) the form [[YYYY]] is at the top with a non-negative year, sorting would be numerical; in this case, after toggling between ascending and descending there would be no proper sorting within each year (because parsefloat is applied, finding the first number in the string, and basing sorting on only that number). Also, years BC would not be sorted properly. Therefore, alphabetic sorting has to be enforced. This can be done by putting a non-displayed character after the year, separated by a space.

See also:

[edit] Secondary sortkey

If a column contains a value multiple times then sorting the column preserves the order of the rows within each subset that has the same value in that column (Template:Mlw). Thus sorting based on a primary, secondary, tertiary, etc. sortkey can be done by sorting the least-significant sortkey first, etc.

First click on column Alphabet and then on Numbers, you'll see that the ordering is on Numbers (1), Alphabet (2).

Numbers Alphabet Dates Currency Text
4 a 01.Jan.2005 4.20 row 1
5 a 05/12/2006 7.15 row 2
1 b 02-02-2004 5.00 row 3
1 a 02-02-2004 5.00 row 4
2 x 13-apr-2005 row 5
2 a 13-apr-2005 row 6
3 a 17.aug.2006 6.50 row 7
3 z 25.aug.2006 2.30 row 8
3 z 28.aug.2006 5.50 row 9
3 z 31.aug.2006 3.77 row 10
3 z 01.sep.2006 1.50 row 11
Bottom

[edit] Keeping some rows together

Partly hidden sortkeys can be used to keep certain rows together. The original mutual order of these rows is preserved.

Example where this is the case for the rows about the Netherlands:

Country/province Capital
France Paris
NetherlandsSouth Holland AmsterdamThe Hague
NetherlandsSouth Holland AmsterdamThe Hague
U.K. London

[edit] Limitations

Javascript sorting may not work properly on tables with cells extending over multiple rows and/or columns (however, sorting of columns up to and including the first with colspan does not seem to be affected). Also, while cells can be empty, they should not be missing at the end of a row. In these cases sometimes the table gets messed up when attempting to sort, while other times some of the sorting buttons work while others don't.

[edit] Colspan workaround

To allow sorting, the formal number of cells in each row should be equal (if not all columns are made sortable this should apply at least for the number of cells up to and including the last sortable column). However, with a CSS hack the number of cells shown in a row can differ from the formal number of cells. For example, two formal cells can be shown as one by specifying a width for the first column, shifting the contents of the second cell to the left, increasing its width by the same amount, and hiding the cell border that would normally be visible. Hidden sortkeys can be used to control, for sorting with respect to each column, how this row should be sorted.

Example:

Country Capital
France Paris
Z M
Sorting with respect to the first column this row sorts like Z, with respect to the second column like M
U.K. London

This can be combined with the method of "keeping some rows together" demonstrated above. For an example of an application of this, consider a table of three columns where the third column would make the table too wide, such as a column of miscellaneous details. These details can be put in separate rows, each staying below the corresponding row when the table is sorted.

Example:

Country Capital
France Paris
In Paris is the Eiffel Tower.
France Paris
In Paris is the Eiffel Tower.
U.K. London
In the U.K. you cannot pay with euros.
U.K. London
In the U.K. you cannot pay with euros.
Germany Berlin
Germany includes the former DDR.
Germany Berlin
Germany includes the former DDR.

A table row template makes this technique less cumbersome to apply, see e.g. w:List of furry conventions, w:Template:Furry-con-list-start and w:Template:Furry-con-list-entry.

[edit] Controlling sorting and display

Text undesired for sorting but needed for display:

  • In numeric sorting mode, this text (e.g. footnotes) needs to be put after the number; if at the top it causes string sort mode. See e.g. Help:Sorting/countries.
  • In date sorting mode, this text needs to be put in a separate column; in the case of a cell containing a range of dates or numbers (e.g. from .. to ..), text in surplus of what is required for sorting is put in the extra column. If the first part of the text is used for sorting, then the extra column needs to be the following one; conversely, if the last part of the text is used for sorting, then the extra column needs to be the previous one; depending on the table format, this dividing of an item over two cells may look ugly.
  • In alphabetic sorting, any footnotes etc. do not require a separate column; they can simply be put at the end of the element.

Text undesired for display but needed for sorting:

  • can be put as hidden text in the column to be sorted

Combining the two, we can have displayed text independent of text used for sorting, by fully hiding the latter, and fully putting the former in a separate column (in date sorting mode and numeric sorting mode) or in the same column after the hidden text (in alphabetic sorting). Fully putting the displayed text in a separate column may look ugly if it is not done consistently for a whole column, but only for elements that require this (e.g. if most entries in a column are single numbers, but some are ranges).

[edit] Static column

A static column, e.g. with row numbers, can be obtained with two side-by-side tables with for each row the same height set in both tables:

Number
1
2
Country Capital
The Netherlands Amsterdam (although The Hague is the seat of government)
France Paris

The style can be adjusted to make it appear as a single table. If for some row the height of that row is too small for the text in a cell on one of the sides, the browser increases it, and there is no longer a match.

[edit] Default order

It is not possible to make a table appear sorted by a certain column without the user clicking on it. By default, the rows of a table always appear in the same order as in the wikitext. If you want a table to appear sorted by a certain column, you must sort the wikitext itself in that order; see the next section for one way to do this.

[edit] Sorting the wikitext of a table

Sorting does not directly sort the wikitext itself. If it is desired to create a new default sort order, you can make an auxiliary sortable table rendered as wikitext for the original table, and then sort the wikitext of the original table.

Example:

Original table:

demo
9
12
11

Auxiliary table:

{|class="wikitable sortable"
!demo

header
|-
| 9
|-
|12
|-
|11

|}

After copying the rendered text to the edit box, and deleting the header line, this renders as a new defaultly sorted table:

demo
9
11
12

[edit] Alphabetic sorting order

demo
!
"
#
$
%
&
'
(
)
*
+
,
-
.
/
0
9
:
;
<
=
>
?
@
[
\
]
^
_
'
A
Z
a
z
A1
Z1
a1
z1
{
|
}
~
É
é
É1
é1

The two-character entries such as A1 demonstrate that A and a are at the same position.

[edit] Browser issues

With older versions of Safari a table can only be sorted by the first column: all sort buttons have the effect that only the leftmost one is supposed to have.

[edit] See also

Examples elsewhere:


Template:H:f

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