## 18.3. Signs and numerical punctuation

The following cmavo are discussed in this section:

 ma'u PA positive sign ni'u PA negative sign pi PA decimal point fi'u PA fraction slash ra'e PA repeating decimal ce'i PA percent sign ki'o PA comma between digits

A number can be given an explicit sign by the use of ma'u and ni'u, which are the positive and negative signs as distinct from the addition, subtraction, and negation operators. For example:

Example 18.5.

 ni'u pa negative-sign 1 -1

Grammatically, the signs are part of the number to which they are attached. It is also possible to use ma'u and ni'u by themselves as numbers; the meaning of these numbers is explained in Section 18.8.

Various numerical punctuation marks are likewise expressed by cmavo, as illustrated in the following examples:

Example 18.6.

 ci pi pa vo pa mu three point one four one five 3.1415

(In some cultures, a comma is used instead of a period in the symbolic version of Example 18.6; pi is still the Lojban representation for the decimal point.)

Example 18.7.

 re fi'u ze two fraction seven 2 7

Example 18.7 is the name of the number two-sevenths; it is not the same as the result of 2 divided by 7 in Lojban, although numerically these two are equal. If the denominator of the fraction is present but the numerator is not, the numerator is taken to be 1, thus expressing the reciprocal of the following number:

Example 18.8.

 fi'u ze fraction seven 1 7

Example 18.9.

 pi ci mu ra'e pa vo re bi mu ze point three five repeating one four two eight five seven .35142857142857...

Note that the ra'e marks unambiguously where the repeating portion 142857 begins.

Example 18.10.

 ci mu ce'i three five percent 35%

Example 18.11.

 pa ki'o re ci vo ki'o mu xa ze one comma two three four comma five six seven 1,234,567

(In some cultures, spaces are used in the symbolic representation of Example 18.11; ki'o is still the Lojban representation.)

It is also possible to have less than three digits between successive ki'o s, in which case zeros are assumed to have been elided:

Example 18.12.

 pa ki'o re ci ki'o vo one comma two three comma four 1,023,004

In the same way, ki'o can be used after pi to divide fractions into groups of three:

Example 18.13.

 pi ki'o re re point comma two two .022

Example 18.14.

 pi pa ki'o pa re ki'o pa point one comma one two comma one .001012001