### The Basis of the Transcription of a Simple Algebra Example in the Nemeth Code

#### Discussion of Nemeth rules used in the previous example.

The transcription of the algebra problem on the previous page illustrates a number of of Nemeth rules which are explained in more detail on this page.

Original source: Example 6. Factor 12x2 + 7xy - 10y2.

ASCII braille:
,,example #6_4 ,factor
#12x^2"+7xy-10y^2_4

Simulated braille:
,,example #6_4 ,factor
#12x^2"+7xy-10y^2_4

Figure. Nemeth transcription of Original source shown in both ASCII and Simulated braille.
##### Transitions between literary and math contexts

No special indicators, such as those used with Computer Braille Code, are used to show the transition from literary portions to mathematical items and expressions in Nemeth; this is assumed to be obvious to the reader as well as the transcriber. In this particular example the Numeric Indicator indicates the start of a mathematical item or expression and the Punctuation Indicator ends it but this is not necessarily always the case.

##### Proper format for labeled statements

According to the Nemeth rules, the label of a labeled statement which uses a non-regular type form in print must be transcribed as though it were entirely capitalized. Thus the boldface label of Fig. 1 on the previous page or the strong tag of the corresponding HTML in Fig. 2 has been replaced by the double or whole word capital sign or repeated (dot 6) cells in braille. Braille avoids the need for a specific "end tag" for the word capitalizer by setting the default that the effect is terminated by the space or punctuation at the end of the word.

##### Nemeth numerals and the use of the Numeric Indicator

If you are familiar with literary braille, you will have noticed that Nemeth uses lower-cell numerals rather than the upper-cell ones. Another difference is that the number sign, called the Numeric Indicator (NI) when used before Nemeth numerals according to the Nemeth code, is not used before all numbers as in literary braille but only in most situations where a number is preceded by a space and also in certain special contexts. (The complete set of rules for using the Nemeth NI are given elsewhere on this site.)

##### The Nemeth Punctuation Indicator

Since Nemeth uses lower-cell numerals, an indicator is sometimes required to show when certain cells are intended as punctuation marks rather than as numerals as before the period in this example. Braille cell (dots 4-5-6) is used for the Punctuation Indicator (PI). (The complete set of rules for using the Nemeth PI are given elsewhere on this site.)

##### Use and Non-use of the Nemeth Letter Indicator
When mathematical variables or symbols like x and y are used in mathematical expressions in Nemeth, an indicator analogous to the mathematical italics produced by HTML's var tag or the literary braille letter sign must not be used. However, as we shall see later, a corresponding indicator, usually called the English-letter Indicator in Nemeth, must precede certain mathematical variables when they are mentioned in a literary context. (The complete set of rules for using the Nemeth English-letter Indicator are given elsewhere on this site.)

##### Superscript and Base-Line Indicators

The Nemeth superscript indicator is (dots 5-6) and functions as the start tag for items used as superscripts. The base-line indicator, which acts as an end tag for the both the superscript and subscript indicators, is (dot 5). However, the base-line indicator is not used when other situations, such as the presence of the Punctuation Indicator in this case, are sufficient to terminate the effect of the superscript (or subscript) indicator. (Note that the rules for the use of subscripts in Nemeth are not completely parallel to the use of superscripts; see other references for details.)

##### Plus and Minus Signs of Operation

The plus sign (dots 3-4-6) and minus sign (dots 3-6) are signs of operation in braille. These signs must never be preceded or followed by a space even when a space is used in print. However, there are some Nemeth signs for which spaces are required and others for which spaces are optional.