Lesson 5.3: Directed Signed
The symbols for plus and minus are also used to indicate directed or signed values. In most cases there is no distinction between a plus or minus sign used as a sign of operation or used to indicate a directed numeral or symbol. A directed numeral designates a value as positive by using the plus sign, or negative by using the minus sign before the numeral or symbol. Usually if a number is positive, the plus sign will not be shown. However, in some cases the plus sign is shown. In addition, the plus and minus signs may be raised. In such cases, the superscript and baseline indicators must be used properly.
Guidelines for the use of plus and minus symbols when used to indicate signed numerals
The guidelines for brailling directed numerals are the same as for brailling these symbols as signs of operation, with one exception. If a negative numeral occurs at the beginning of a braille line or after a space, the numeric indicator should be placed between the minus sign and the numeral. This aids in the correct interpretation of the symbols since the numeric indicator provides a reference for the vertical placement of the braille dots. In all other cases, the numeric indicator is not required. The use of signed numerals following signs of comparison, such as the equals sign, will be presented in subsequent lessons.
If the minus sign is raised in front of the number, the numeric indicator is not used.
positive six with a raised plus sign
positive six with the plus symbol on the same level as the six
negative six with a raised minus sign
negative six with the minus symbol on the same level as the six
negative seven comma positive two with raised minus and plus signs
negative seven comma positive two with all plus and minus signs on the same level as the numbers
positive one plus negative nine with raised plus and minus signs for the positive and negative
negative three with a raised minus sign, plus a positive six with a raised plus sign
negative two plus open parenthesis plus seven close parenthesis, with all plus and minus signs on the same level as the numbers.