Number notation#
There are many different ways of writing a number, depending on culture and context.
Numbas can interpret and display numbers in several styles.
Styles of notation#
Numbas supports the following styles of notation. The entry in the “Code” column is the string you should use to identify the style in JME or JavaScript code.
Style |
Code |
Description |
Example |
|---|---|---|---|
English (plain) |
|
Powers of 1000 not separated, and a dot is used for the decimal mark. |
1234567.890123 |
English |
|
Positive powers of 1000 are separated with commas, and a dot is used for the decimal mark. |
1,234,567.890123 |
SI (English) |
|
Powers of 1000 are separated with spaces, and a dot is used for the decimal mark. |
1 234 567.890 123 |
SI (French) |
|
Powers of 1000 are separated with spaces, and a comma is used for the decimal mark. |
1 234 567,890 123 |
Continental |
|
Positive powers of 1000 are separated with dots, and a comma is used for the decimal mark. |
1.234.567,890123 |
Continental (plain) |
|
Powers of 1000 are not separated, and a comma is used for the decimal mark. |
1234567,890123 |
Swiss |
|
Positive powers of 1000 are separated with apostrophes, and a dot is used for the decimal mark. |
1’234’567.890123 |
Indian |
|
Groups of digits in the integer part are separated with commas. The rightmost group is three digits, and other digits are grouped in pairs. A dot is used for the decimal mark. |
12,34,567.890123 |
Scientific |
|
A mantissa between 1 and 10, formatted using the ‘plain’ style, then the letter ‘e’, followed by a signed integer exponent. |
1.234567e+6 |
Warning
Note that some styles conflict with each other: for example, 1.234 is a number between 1 and 2 in English, while it’s the integer 1234 in French.
In the JavaScript runtime, these styles are defined in Numbas.util.numberNotationStyles.
Numbers in JME#
In JME code, and Mathematical expression parts, numbers are written in the “English (plain)” form only.
You can parse a string representing a number written in a different style using the parsenumber function, and display it using a particular style using the formatnumber function, or by giving a style code to dpformat or sigformat.