Lesson 3.5: Omission Symbol
There are circumstances when it is necessary to indicate that an item has been omitted or that information is to be filled in by the student. In print, omissions are often represented by a blank space, a question mark that is not used as a mark of punctuation, or a line with a question mark on it. An omission can also be represented by an ellipsis, a long dash, or a hollow shape such as a square, circle, or triangle. The general sign of omission is a full braille cell, dots one-two-three-four-five-six. It is a mathematical symbol and all of the rules that apply to mathematical symbols apply to the general sign of omission. These rules are determined by the specific type of symbol which the general sign of omission represents. For example, if it represents a missing number, then the symbol is spaced as if it were a number. If it is being used to represent an omitted sign of operation, then the rules governing signs of operation apply to it. If it is used to indicate that a sign of comparison such as the equals sign is omitted, then it should have a space before and after it.
A simple addition equation that shows this is shown below:
six plus question mark equals ten
This would be read six plus a missing value equals ten.
In this case, the missing number is 4 since six plus the missing number four would equal ten.
Although the print symbol may vary greatly from a blank space, a question mark, or a question mark over a line, in braille only the full cell is used.
six question mark four equals ten
In this example, the operation is missing. The student needs to decide what operation between six and four would equal ten. Thus, the answer for the missing operation would be the plus symbol since six plus four equals ten.
The general omission symbol can be used for material presented both spatially and horizontally.
The ellipsis as an omission symbol
An ellipsis is displayed in print as a series of three periods. In braille, this pattern is represented by a series of three cells: dot three, dot three, dot three. The ellipsis is most often used to indicate a series of omitted characters which follow a pattern, as in example #3, or which are between two values as in example #4. Unlike the general sign of omission, the ellipsis usually has a space before the first dot three and after the last dot three. There are exceptions to this rule.
In this example we show an unending sequence of numbers.
two comma four comma six comma eight comma ten comma ellipsis
In this example, the ellipses represent a pattern of omitted numbers in a sequence.
five comma ten comma fifteen comma ellipsis one hundred
The ellipsis is to be punctuated as a mathematical symbol when it is used mathematically. It is punctuated according to literary rules when it is used in a literary context. If a mark of punctuation follows the ellipsis when it is used in a mathematical context, the Closing Nemeth Indicator is placed between the sign of omission and the punctuation with spaces before and after.
In this example, the ellipses are used as a mathematical symbol followed by a mark of punctuation.
two comma four comma six comma eight comma ten comma ellipsis period
The long dash as an omission symbol
The long dash is composed of four cells of dots three six, and is often used as a blank line to show a blank or omitted item.
In this example, the long dash is used to show an omitted numeral in an equation.
five plus seven long dash equals ten
seven plus long dash plus four equals fifteen
The requirement to space before and after the long dash or ellipsis does not apply in the following situations:
- when punctuation is associated with the symbol.
- when it is associated with a related monetary symbol such as the dollar sign, cent sign, or percent sign.
- when it is associated with a braille indicator such as the numeric indicator or English letter indicator.
- when it is adjacent to a sign of grouping, such as parentheses or brackets.
long dash with punctuation
three comma six comma nine commas long dash.
long dash with an omitted money amount
2 times four point zero zero dollars equals long dash dollars.
Sometimes the multipurpose indicator, the dot five, is needed before the long dash. This is because the long dash is not a numeral even though it represents a missing number. This happens when the long dash comes after a decimal point.
2 times point two six equals long dash dollars.
Other signs of omission are presented in later sections.