Bản mẫu:Giá trị
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This template is used to easily present values in scientific notation, including uncertainty and/or units, as prescribed by Wikipedia's Manual of Style.
Chú ý: Các tham số đầu vào phải tuân theo quy tắc tiếng Việt: |1=1.234,5678 hoặc |1=1234,5678, chứ không phải |1=1,234.5678.
Sự giới thiệu
sửaVal stands for the number value that is its first parameter. Val specializes in scientific notations and uncertainty notations, and in a measurement value with physical units. It formats the number (with possible unit) according to the Manual of Style and keeps the expression from wrapping across lines.
Express a numeral:
{{val|123456.78901}}→ value, formated with gaps: 12345678901, or with|fmt=commas→ 12345678901.{{val|number|number}}→ value ± uncertainty, like 123478±56{{val|number|(number)}}→ value(uncertainty), like 12345(56).{{val|number|number|number}}→value +uncertainty
−uncertainty like 1234+56
−78
Express a measurement value with a unit, for example {{val|4|ul=m/s2}} → 4 m/s2. The keyboard characters m/s2 are a "unit code" that |u=m/s2 marks up, or that |ul=m/s2 additionally links to its articulation.
Because the unit spacing and markup is a style issue, Val provides these for you. There are a large number of unit codes that Val understands and keeps "up to code". A unit code is usually composed of one or more abbreviated unit names and the usual math symbols on the typical keyboard. See {{Val/units}}.
Some unit-code flexibility is provided by having four parameters to work the unit-code system: whether to link one or not, (see Overlinking) , and whether to form a ratio or not with a unit code.
{{val|number|u=unit code}}→ number markup , such as 98 m/s2{{val|number|ul=unit code}}→ number [[Article|markup]], such as 98 m/s2{{val|number|u=unit code|upl=unit code}}→ number markup/[[Article|markup]], such as 98 m/s2{{val|number|ul=unit code|up=unit code}}→ [[Article|markup]]/markup, such as 98 m/s2
To bypass the unit code system, if |u= does not recognize your unit code, it will accept any wikitext and render it as usual.
{{val|5.4|u=[[kg]]⋅[[meter|m]]/s<sup>2</sup>}}→ 54 kg⋅m/s2{{val|7.6|u=[[metre per second squared|m/s<sup>2</sup>]]}}→ 76 m/s2
See below for § How to add units to the unit code system.
Sometimes a number and unit code is not enough. A prefix or suffix are also available, |p= and |s=.
{{val|7600|u=C⋅Ga|p=>|s=<}}→ >7600 C⋅Ga<{{val|7600|u=C|p=<span style="color:green"><sup>|s=</span></sup>}}→ 7600 C
See {{val/testcases}} to learn the val parameters by a example. It's comprehensive, and there's over 100 examples.
Arguments
sửa| 1st | The numeric basis of the value. Defaults to 100.
|
| 2nd | Uncertainty in either format.
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| 3rd | Asymmetric uncertainty.
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|e=
|
Exponential.
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|fmt=
|
Format strings of digits. Accepts |fmt=commas for the integer part, but commas ignores the fractional part. Defaults to gaps, except for four digits. Four digits accept |fmt=gaps.
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|u= or |ul= |
The unit code. Val adds a space and the unit.
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|up= or |upl= |
A unit code, but Instead of a space Val adds a slash and the unit, a "per" unit (the denominator), to form a ratio.
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|p= |
Prefix. Non-spaced, but accepts markup.
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|s= |
Suffix. Non-spaced, but accepts markup.
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|end= |
Add something between the base number and what follows. This is how Val can do numeric ranges.
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|errend= or |+errend= and |-errend= |
Appends something after an uncertainty.
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|sortval= |
Alternative sorting factor to 1 |
|us= or |ups= |
Alternative unit code for sorting. |
|long scale= |
Usually a unit is the short ton and billion means 1×109. But there are long versions of these units and others. Use |long scale=on to assign your unit to the long scale instead. The unit code's link will change and it will sort differently in tables. "See Long and short scales".
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|nocategory= |
If set to any value, errors in the use of this template will not cause the page to be added to the Pages with incorrect formatting templates use category. This is useful for documentation and test pages that do not need to be fixed. |
Các lỗi
sửaThere is strict checking on the validity of arguments; any incorrect use will result in an error, which is displayed using {{FormattingError}}. Pages that contain incorrect use of this template will show up on Category:Pages with incorrect formatting templates use.
Định dạng của các số
sửa{{Val}} produces formatting compliant with Wikipedia's Manual of Style.
The MOS recommends that numbers either be delimited using thin spaces either side of the decimal, or commas to the left and no delimiters to the right. Articles should be consistent with respect to the style of delimiting. The template defaults to the former style, this can be adjusted using |fmt= (see above).
Sắp xếp
sửaA hidden sort key is added to the output for sorting in sortable tables. The sort key is based on the main value (parameter |1=) and, if used, the exponent for the power of 10 (parameter |e=) and/or units (parameters |u=, |ul=, |up= and/or |upl=). Where necessary, units are converted to base SI units for the purpose of the sort key, which is produced by {{ntsh}}. Several units are covered; see § How to add units for those which are not. To omit the sort key use |sortable=off.
Ví dụ
sửa- Number
{{val|1234567.1234567}} → 12345671234567
{{val|.1234567}} → 1234567
{{val|+1234567}} → +1234567
{{val|-1234567}} → −1234567
- Uncertainty
{{val|1.234|0.005}} → 1234±0005
{{val|1.234|+0.005|-0.006}} → 1234+0005
−0006
{{val|1.234|(5)}} → 1234(5)
- Units
{{val|1.234|u=m}} → 1234 m
{{val|1.234|u=m2}} → 1234 m2
{{val|1.234|ul=m}} → 1234 m
{{val|123.4|ul=USgal}} → 1234 gal Mỹ
{{val|12.34|ul=mpgimp}} → 1234 mpg‑Anh
{{val|12.34|u=deg}} → 1234°
{{val|1.234|0.005|u='}} → 1234′±0005′
{{val|1.234|+0.005|-0.006|u="}} → 1234″+0005″
−0006″
- Exponents
{{val|1.234|e=5|ul=m}} → 1234×105 m
{{val|1.234|0.056|e=7}} → (1234±0056)×107
{{val|1.23456|+0.00007|-0.00008|e=-9|ul=m/s}} → 123456+000007
−000008×10−9 m/s
{{val|1.234|0.056|e=7|ul=psi}} → (1234±0056)×107 psi
{{val|1.234|(5)|e=-2}} → 1234(5)×10−2
- Prefix/suffix
{{val|12.34|p=Δ }} → Δ 1234
{{val|12.34|u=%|p=≅}} → ≅1234%
{{val|12.34|0.25|s=%}} → 1234±025%
- Numerator/Denominator
{{val|1.234|e=7|ul=W|up=m2}} → 1234×107 W/m2
- Even more examples
See the testcases at {{val/testcases}}.
Performance impact
sửaFor very long list articles with hundreds of numeric entries, load times for that page will be much much faster by using html. No templates can compete with HTML on, for example List of nuclides.
Performance data is reported by MediaWiki software in the HTML page source of every page, and a very similar report is available on any preview page, below the edit box, titles "Parser profile data". For using Val inside other templates, note the performance parameter in these reports, called "Highest expansion depth". Numbers with fractional parts cost more Val-expansion depth than numbers with only integer parts.
For uses in any other page besides long list articles, Template:Val will have no noticeable impact on CPU time contributions to page-load times.
How to add units
sửaAdd the unit to Bản mẫu:Val/units. Val defaults to looking up units at {{Convert}}, but units added here override that.
Note these points about composite units before adding units:
- For composite units you should probably link the whole, not individual units. For example the line you add would say
|m.s-1=[[Metre per second|m⋅s{{sup|−1}}]]linking to Metre per second, not|m.s-1=[[Metre|m]]⋅[[Second|s]]{{sup|−1}}.
- List of common physics notations has many examples of composite units that have their own page.
- The val user can compose their own divisor unit from an existing unit, for example writing
{{val|99|ul=m|upl=s}}to render their own "99 m/s" with two links:mto Meter andsto Second. - The val user can compose their own multiplier units by using the
endparameter to prepend a string. For example, in a geology article, to prepend "Ma", to the unit in 333 14C yr BP, use{{val|333|ul=uBP|end= [[megaannum|Ma]]}}→ 333 Ma 14C yr BP". (Theendparameter accepts wikitext, so it can be linked.)
After adding a unit, you can ensure that it sorts correctly in a table, especially if there are ten or twenty variations that differ only by an SI prefix. (See § Sorting above and Bản mẫu:Val/sortkey/unit.)
FAQ and comments
sửa- Q: Why should I use Val?
- A1: Val formats numbers:
- inserts spaces between groups of digits, approximating SI standards
- properly formats uncertainties in measurements and significant digits, providing a ± character, etc.
- properly formats exponents of 10 and scientific notation
- replaces "-" (hyphen) with a "−" (minus sign)
- A2: Val preserves spacing:
- It makes sure the value does not wrap at the end of a line, so that it can always be read as a single value on one line in the text.
- It spaces the various parts of the value where they should be
- A3: Configuring Val gives you your own code for automating the markup for, and a link to, any units in the entire Encyclopedia.
- A4: Val helps make Wikipedia more consistent. It adheres to the Wikipedia Manual of Style for numbers. Updates to the MoS can be applied to this template, and result in automatic modification on values that use it. All this makes sure all values on all pages have the same look and feel because they will all use the same spacing, font size, positioning, etc, and makes updating and checking by the bots easier because they can recognize a value for what it is.
- Q: Why not use <math>?
- A: For the same reasons HTML might be preferred over TeX:
- Because the font in math tags differs both in face and size from the prose, which can disturb the layout of a page when used inline with the prose.
- You cannot cut and paste a bitmap image rendered by the Latex.
- Images are slower to load and use more bandwidth, which is especially bad for the mobile version of Wikipedia.
- <math> does not automatically easily align to the Manual of Style for numbers.
- Q: Are there any known issues with Val?
- A1: This template has been in full use on many pages for quite some time without major problems or breaking changes. Technically, there is no good reason not to try Val.
- A2: Issues are solved rapidly by an active set of responsive template coders. See the talk page.
- Q: How should I use Val?
- A1: Val probably already has your unit on its current list. If not, then your unit can be added.
- A2: To avoid over linking switch from
|ul=to|u=and from|upl=to|up=. - A3: Use Val along with {{Convert}}. See how to add units to Convert.
Xem thêm
sửa- {{Val}} subtemplates:
- {{Val/units}}, for the list of customized units, their markup, their link, and to configure your own codename for your own unit (whose name you choose goes into any of the named parameters with the letter
uin there names). - Similarly {{Val/angle}}, for the handling of unspaced units.
- {{val/delimitnum}}, for setting your own delimiters between groups of digits instead of using the default (spaces).
- {{Val/sortkey/unit}} for guaranteeing table sorting
- {{Val/units}}, for the list of customized units, their markup, their link, and to configure your own codename for your own unit (whose name you choose goes into any of the named parameters with the letter
- {{formatting error}}, to fix inconsistencies when the error you are given is not the error you find you have.