Template:Calculator

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This template is for creating interactive calculators. It requires the calculator gadget. The calculator works by default. You can opt out at: Preferences > Gadgets > Template Gadgets > Enables javascript Calculator template.

You can use this template multiple times on a page to make input widgets, with some of the widgets having formulas based on other widgets, like a spreadsheet.

You can use {{Calculator label}} to mark text as a label for a calculator widget.

Statistics for this template are available at [1]

Examples

{{calculator|id=a|default=2|size=4}} × {{calculator|id=b|default=2|size=4}} = {{calculator|id=c|formula=a*b|default=4|type=plain}}

produces:

2 × 2 = 4

{{calculator|id=km|type=number|size=9|default=1.609344|formula=miles*1.609344}} km = 
{{calculator|id=miles|type=number|size=9|default=1|formula=km/1.609344}} miles 

produces:

1.609344 km = 1 miles

BMI calculator metric

You can put widgets inside a wikitable.

{| class="wikitable" style = "float: left; margin-left:15px;"
|+ Metric
|-
| {{calculator label|Weight|for=weightkg}} || {{calculator|id=weightkg|size=3|default=80}} kg
|-
| {{calculator label|Height|for=heightcm}} || {{calculator|id=heightcm|size=3|default=160}} cm
|-
| BMI || '''{{calculator|id=bmimetric|type=plain|formula=round(weightkg/pow(heightcm/100,2))|default=31|style=min-width:3ch;display:inline-block}} kg/m<sup>2</sup>'''
|}

Metric

Weight	80 kg
Height	160 cm
BMI	31 kg/m2

BMI calculator imperial

You can also put widgets inside an HTML table.

<table class="wikitable">
<tr><td>Imperial</td></tr>
<tr><td>Weight</td><td>{{calculator|id=weight|size=3}} lbs</td></tr>
<tr><td>Height</td><td>{{calculator|id=heightFeet|size=1}} feet {{calculator|id=heightInches|size=2}} inches</td></tr>
<tr><td>BMI</td><td>'''{{calculator|id=bmi|type=plain|formula=round(100*weight*703/pow(heightFeet*12+heightInches,2))/100}} kg/m<sup>2</sup>'''</td></tr>
</table>

Imperial
Weight	lbs
Height	feet inches
BMI	kg/m2

Other

• mdwiki:CHA2DS2–VASc score

Buttons

When pressed, the {{calculator button}} updates a form field.

{{calculator button|contents=Click me!|for=buttoncount|formula=buttoncount+1|type=plain}} 

The button has been clicked {{calculator|type=plain|default=0|id=buttoncount}} times.

Click me!

The button has been clicked 0 times.

Labels

A {{calculator label}}

1. adds a text label to a calculator widget, improving its accessibility
2. when clicked, give focus to the input widget, especially helpful for small widgets
3. selects/deselects a checkbox/radio target.

{{calculator|type=checkbox|id=checklabelex}} {{calculator label|label=Please click this label|for=checklabelex}}

Please click this label

Formula

Formulas use normal math syntax, with english words representing other input boxes. e.g. sin(1+foo*2) would multiply the foo box by 2, add 1 and take the sine of the whole thing. All calculations are done using IEEE 754 double precision floating point numbers.

Supported operators

Operators supported include: +, -, *, ×, /, ÷, % (percent is the modulo operator). Exponentiation must use the pow() function.

Math functions

Math functions supported include: 'abs', 'acos', 'acosh', 'asin', 'asinh', 'atan', 'atan2', 'atanh', 'ceil', 'cos', 'cosh', 'exp', 'floor', 'hypot', 'log', 'log10', 'log2', 'max', 'min', 'pow', 'random', 'sign', 'sin', 'sinh', 'sqrt', 'tan', 'tanh', 'trunc'

These have the same definition as in javascript. In particular, that means that log() is log base-e. The exception is round, which we use our own definition of.

Additional functions

The following additional functions are supported which are not from javascript Math library:

and

Logical and of all arguments (can take more than 2). This operator short circuits like lua, and returns first false argument. Wrap in bool() if you want a 1 or a 0

bool

Return 0 if value is very close to 0 or NaN, otherwise 1

coalesce

return the first argument that is not NaN.

ifbetween

return either fourth or fifth argument depending on if the first argument is between the second or third argument. Comparison is not fuzzy. The last two arguments are optional and default to 1 and 0 respectively.

ifequal

If first and second argument are the same, accounting for floating point error. The last two arguments are optional and default to 1 and 0 respectively.

iffinite

if the first argument is finite return second argument, otherwise return third argument. The last two arguments are optional and default to 1 and 0 respectively.

ifgreater

return third or fourth argument depending on if first argument is > second argument. Comparison is fuzzy to account for floating point error. Use ifpositive() if you don't want that. The last two arguments are optional and default to 1 and 0 respectively.

ifgreaterorequal

return third or fourth argument depending on if first argument is >= second argument. Comparison is fuzzy to account for floating point error. Use ifpositive() if you don't want that. The last two arguments are optional and default to 1 and 0 respectively.

ifless

Return third or fourth argument depending on if first argument is < second argument. Comparison is fuzzy to account for floating point error. Use ifpositive() if you don't want that. The last two arguments are optional and default to 1 and 0 respectively.

iflessorequal

return third or fourth argument depending on if first argument is <= second argument. Comparison is fuzzy to account for floating point error. Use ifpositive() if you don't want that. The last two arguments are optional and default to 1 and 0 respectively.

ifnan

if first argument is not a number (NaN), return second argument, otherwise third argument. The last two arguments are optional and default to 1 and 0 respectively.

ifpositive

if first argument is ≥ 0 return second, otherwise return third. Note this does not account for floating point rounding. You can use this if you need precise control over the comparison. The last two arguments are optional and default to 1 and 0 respectively.

ifzero

if first argument is epsilon away from zero, return second argument, otherwise third argument. The last two arguments are optional and default to 1 and 0 respectively.

index

Allows treating variables like an array with an index evaluated at runtime. index( foo, 2+3 ) is the same as foo5. The first argument must be an identifier (Nested index() is not allowed). The second argument must evaluate to an integer greater than or equal to 0. If either of these two arguments are invalid, NaN is returned. The third argument is returned if the arguments are valid but the result references a variable that does not exist. If unspecified the third argument defaults to NaN.

jsround

Use javascript round. This does round half towards positive infinity with a precision of 0. See mdn docs

not

Return 1 if value is very close to 0 or NaN, otherwise 0

or

Logical or of all arguments (can take more than 2). This operator short circuits like lua, and returns first true argument. Wrap in bool() if you want a 1 or a 0

round

A round function. Unlike javascript round(), this implements round half away from zero ("commercial rounding"). It takes an optional second argument to say how many decimal digits to rount to. e.g. round( 3.125, 2 ) = 3.13, round( -3.125, 2 ) = -3.13.

xor

Logical exclusive or. Can only take 2 arguments, always return 1 or 0.

Numbers

Numbers can be

• integers
• decimals
• scientific notation. For example: 1, 2.84543, 3.12E6, -5, 3.45×10⁻⁴⁵

Supported constants

• Infinity
• -Infinity
• NaN
• pi
• π
• EPSILON

Scoping

If the calculator widgets are contained within an element with the class calculator-container, then the ids are scoped to this element. This allows you to use the same ids multiple times on the same page without them interfering with each other. If the scoping element has the attribute data-calculator-refresh-on-load="true", then the calculator widgets are refreshed on first page load before the user interacts with it.

For example:

	
<div class="calculator-container" data-calculator-refresh-on-load="true">
{{calculator label|scopedfield:}} {{calculator|type=text|id=scopedfield|default=3.14}}<br>
This formula is updated before user interaction: {{calculator|type=plain|formula=scopedfield|default=No value}}
</div>
This formula is not updated because it is in a different scope: {{calculator|type=plain|formula=scopedfield|default=No value}}

Produces the following:

scopedfield: 3.14
This formula is updated before user interaction: No value

This formula is not updated even after user interaction because it is in a different scope: No value

Instead of using the css classes directly, you can also use the {{Calculator ifenabled}} with the scoped parameter.

CSS

You can use CSS to adjust the display, either via TemplateStyles or inline styles.

• For checkboxes and radio buttons, you can use the :checked pseudo selector. This can be very useful when combined with sibling css selectors (~) or :has()
• You can look for the class names calculator-value-true and calculator-value-false. This is especially useful with the passthru type of field. See {{Calculator-hideifzero}} for an example.
• You can target the data-calculator-field-value attribute. e.g. #calculator-field-fieldidhere[calculator-field-scopedfield^="3."] would select the field if it is >= 3.0 and < 4.0.
• You can use css variables for more complex calculations (Only in inline styles)

Some examples:

Adjust color of border:  30

Superimpose an image with coordinates based on a calculator widget:

Height: 178 cm.  Waist: 155 cm.

Codex

It is possible to make widgets be in MediaWiki (Codex) style instead of OS style. You can use most codex widgets that have a CSS-only version. See https://doc.wikimedia.org/codex/latest/components/demos/

Many codex style widgets have separate templates. When making a label, the {{Calculator label}} template has a parameter to output a codex style label

Template	Example
{{Calculator codex text}}	Label textShort description text 42
{{Calculator codex radio}}	This is a group of options First optionAdditional text describing the first option Second optionAdditional text describing the first option Thid option
{{Calculator codex checkbox}}	First optionAdditional text describing the first option
{{Calculator codex toggle}}	My toggleAdditional text describing the toggle
{{Calculator button}}	default progressive destructive default progressive destructive

See the individual template doc pages for all the options.

Fallback

Users who do not have the gadget enabled in their preferences or have JS disabled, will not see the input boxes. Instead they will just see the default value for each box. With a good choice of default, this can be sufficient.

For example, if you have ''sin({{calculator|id=sine|type=text|default=0.5|size=4}}π)={{calculator|type=plain|default=1.00|decimals=2|formula=sin(sine*π)|id=sineres}}'' to make sin(0.5π)=1.00, the non-js user will lose the interactivity, but they will still see the equation.

If you want more sophisticated fallbacks, you can use the calculatorgadget-enabled and calculatorgadget-fallback CSS classes.

<div class="calculatorgadget-enabled" style="display:none">This text is only shown if the gadget is enabled. {{calculator|type=text|size=20|default=100|id=xyz}} </div>
<div class="calculatorgadget-fallback">This text is only shown if the gadget is disabled</div>

Which produces:

This text is only shown if the gadget is enabled. 100

This text is only shown if the gadget is disabled

Alternatively, you can use the {{Calculator ifenabled}} template to do this.

Template arguments

For all types

id

The id for this field, English characters only, used in formulas of other fields. It must be unique on the page. Can be omitted if the field is not used as a value in any formulas.

default

The starting value

formula

The formula to calculate this field. See above for what is supported

placeholder

Placeholder text that shows up light grey when there is no input

readonly

Make field read only

size

how big to make the input box (In terms of number of letters that can fit in the box)

style

Custom CSS to use for the element.

class

Extra class to add to the element

class-live

CSS class to add only if the gadget is active on the page. Added after widgets are processed.

type

Type of field. Currently supported are number, text, plain, radio, checkbox, range, hidden, passthru.

checkbox	1Wet
	0 Big
hidden	160 Not visible, does not take space. Useful for intermediate results in formulas.
number	80
passthru	Is not visibly changed but the css class changes based on the formula User:Bawolff, I've set the formula to =wet, the checkbox above. Now what should happen?
plain	2
radio	1 Metric
	0 Imperial
text	160
range	160 160

Checkbox, hidden and radio can be useful in combination with TemplateStyles to hide and show fields, see Template:Body_roundness_index and Template:BMI calculator2/bmi.css for an example.

For number and range type only

max

Max number allowed (number type only)

min

Min number allowed (number type only)

step

How big the interval is for type=number and type=range inputs. Can be a number or the value "any"

For radio type only

name

When using type=radio, the name of the radio group.

For plain and text type

decimals

Format field to this many decimal digits. (Only works type=plain and type=text)

exponential-precision

Format field to this many significant digits in scientific notation. (Only works type=plain and type=text)

NaN-text

Use this text instead of NaN when result is not a number (Only works type=plain and type=text)

precision

Format field to this many significant digits. (Only works type=plain and type=text)

Add a calculator widget to the page. Like a spreadsheet you can refer to other widgets in the same page.

Template parameters[Edit template data]

Parameter		Description	Type	Status
id	id	The id for this input. This is used to reference it in formula of other calculator templates	String	required
type	type	What type of input box Suggested values plain number text radio checkbox passthru hidden range	String	required
formula	formula	Formula to calculate this field Example 3*log(a)	String	suggested
readonly	readonly	Make input box readonly to user input	Boolean	optional
size	size	Size of input box (How many characters it will fit)	Number	optional
max	max	max number allowed (type=number inputs only)	Number	optional
min	min	min number allowed (type=number inputs only)	Number	optional
placeholder	placeholder	Text to put as a placeholder in empty input	String	optional
step	step	How much to increment a type=number input box Example 2.5	Number	optional
default	default	Default value for this field	String	suggested
style	style	CSS to style the input element with	String	optional
name	name	For type=radio what group to assign the radio button to	Unknown	optional
precision	precision	Format to this many significant digits, using decimal notation except for really large numbers [Only applies to type=number or type=plain] Example 2	Number	optional
exponential-precision	exponential-precision	Format to this many significant digits, using scientific notation [Only applies to type=number or type=plain] Example 2	Number	optional
decimals	decimals	Format to a fixed number of decimal digits [Only applies to type=number or type=plain] Example 2	Number	optional
NaN-text	NaN-text	Use this text instead of NaN to signify "not a number". Only applies to format=plain or format=text. Plaintext only; wikitext is not supported Example Invalid calculation	String	optional
class	class	CSS classes to add	String	optional
class-live	class-live	CSS class to add only if gadget is active on the page	String	optional

The above documentation is transcluded from Template:Calculator/doc. (edit | history)
Editors can experiment in this template's sandbox (create | mirror) and testcases (create) pages.
Add categories to the /doc subpage. Subpages of this template.