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:
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:
(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 is the name of the number twosevenths; 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:
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.
(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:
In the same way, ki'o can be used after pi to divide fractions into groups of three: