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Real Number Formatting

WiP.RealNumberFormatting History

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2010-01-14 19:30 by benjk -
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2010-01-14 17:53 by benjk -
Added lines 110-117:

Affected Types

  • pervasive type REAL
  • pervasive type LONGREAL
  • standard library type BCD
  • standard library type LONGBCD
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2010-01-14 17:50 by benjk -
Added lines 108-109:

whereby TypeOf(realnum) is to be replaced by the name of the real number type.

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2010-01-14 17:32 by benjk -
Added line 20:
Added line 43:
Added line 74:
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2010-01-14 17:31 by benjk -
Added line 95:
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2010-01-14 17:28 by benjk -
Deleted line 73:
Deleted line 96:
Added lines 102-103:

WRITEF( file, realnum, i, n ); shall expand to: TypeOf(realnum).WriteFixed( file, realnum, i, n );

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2010-01-14 17:26 by benjk -
Changed lines 101-103 from:

WRITE( file, realnum ); shall expand to: `Type Of?(realnum).Write( file, realnum );

WRITEF( file, realnum, n ); shall expand to: `Type Of?(realnum).WriteF( file, realnum, n );

to:

WRITE( file, realnum ); shall expand to: TypeOf(realnum).Write( file, realnum );

WRITEF( file, realnum, n ); shall expand to: TypeOf(realnum).WriteF( file, realnum, n );

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2010-01-14 17:26 by benjk -
Changed lines 75-76 from:

The standard IO library shall provide the following output procedures for every real number type that is provided by the language core or by the standard library.

to:

The standard IO library shall provide the following output procedures for every real number type that is provided by the language core or by the standard library. It shall be recommended that user libraries implementing real number types also provide these procedures.

Added lines 96-103:

Mapping of WRITE and WRITEF macros

The compiler shall expand the WRITE and WRITEF macros when invoked with a real number argument as follows:

WRITE( file, realnum ); shall expand to: `Type Of?(realnum).Write( file, realnum );

WRITEF( file, realnum, n ); shall expand to: `Type Of?(realnum).WriteF( file, realnum, n );

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2010-01-14 17:15 by benjk -
Changed line 75 from:

The following output procedures shall be provided for every real number type, whether pervasive or library supplied.

to:

The standard IO library shall provide the following output procedures for every real number type that is provided by the language core or by the standard library.

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2010-01-14 17:13 by benjk -
Added lines 74-75:

The following output procedures shall be provided for every real number type, whether pervasive or library supplied.

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2010-01-14 17:09 by benjk -
Changed lines 85-86 from:

shall produce output in engineering format with n places before, m places after the decimal point and exponent exp. parameters m and exp shall be rounded to the nearest multiple of three.

to:

shall produce output in engineering format with n places before, m places after the decimal point and exponent exp, whereby parameters m and exp shall be rounded to the nearest multiple of three.

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2010-01-14 17:08 by benjk -
Added line 86:

parameters m and exp shall be rounded to the nearest multiple of three.

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2010-01-14 17:05 by benjk -
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2010-01-14 16:58 by benjk -
Changed line 45 from:
  ( '+' | '-' )? decimalDigit decimalDigit? decimalDigit? ( ',' digitGroup )*
to:
  ( '+' | '-' )? whitespace* decimalDigit decimalDigit? decimalDigit? ( ',' digitGroup )*
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2010-01-14 16:54 by benjk -
Added line 76:
Added line 80:
Added line 84:
Added line 88:
Added line 92:
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2010-01-14 16:54 by benjk -
Changed line 78 from:

[@PROCEDURE Write F?( f : File; r : <Real Type?>; n : CARDINAL );

to:

PROCEDURE WriteF( f : File; r : <RealType>; n : CARDINAL );

Changed line 81 from:

[@PROCEDURE Write Eng?( f : File; r : <Real Type?>; n, m, exp : CARDINAL );

to:

PROCEDURE WriteEng( f : File; r : <RealType>; n, m, exp : CARDINAL );

Changed line 84 from:

[@PROCEDURE Write Ledger?( f : File; r : <Real Type?>; i, n : CARDINAL );

to:

PROCEDURE WriteLedger( f : File; r : <RealType>; i, n : CARDINAL );

Changed line 87 from:

[@PROCEDURE Write Fixed?( f : File; r : <Real Type?>; i, n : CARDINAL );

to:

PROCEDURE WriteFixed( f : File; r : <RealType>; i, n : CARDINAL );

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2010-01-14 16:53 by benjk -
Added lines 73-88:

IO Procedures for Real Number types

PROCEDURE Write( f : File; r : <RealType> ); shall produce output in scientific format with 9 places after the decimal point.

[@PROCEDURE Write F?( f : File; r : <Real Type?>; n : CARDINAL ); shall produce output in scientific format with n places after the decimal point.

[@PROCEDURE Write Eng?( f : File; r : <Real Type?>; n, m, exp : CARDINAL ); shall produce output in engineering format with n places before, m places after the decimal point and exponent exp.

[@PROCEDURE Write Ledger?( f : File; r : <Real Type?>; i, n : CARDINAL ); shall produce output in ledger format with the decimal point at index i and n places after the decimal point.

[@PROCEDURE Write Fixed?( f : File; r : <Real Type?>; i, n : CARDINAL ); shall produce output in simple format with the decimal point at index i and n places after the decimal point.

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2010-01-14 16:31 by benjk -
Changed lines 18-19 from:
  • places after decimal point
to:
  • number of places after decimal point
Changed lines 38-39 from:
  • places before decimal point
  • places after decimal point
to:
  • number of places before decimal point
  • number of places after decimal point
Changed lines 57-58 from:
  • places after decimal point
to:
  • number of places after decimal point
Changed line 71 from:
  • places after decimal point
to:
  • number of places after decimal point
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2010-01-14 16:30 by benjk -
Changed lines 15-16 from:

Example: 1.234,567,890+E00

to:

Example: 1.234,567,890E+00

Formatting parameters:

  • places after decimal point
Added lines 37-41:

Formatting parameters:

  • places before decimal point
  • places after decimal point
  • exponent
Added lines 55-58:

Formatting parameters:

  • index of decimal point in output field
  • places after decimal point
Added lines 68-72:

Formatting parameters:

  • index of decimal point in output field
  • places after decimal point
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2010-01-14 16:17 by benjk -
Changed line 49 from:

ledgerReal :

to:

simpleReal :

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2010-01-14 16:16 by benjk -
Changed lines 32-33 from:

Example: 1,234.456,789E+03

to:

Example: 1,234.567,890E+03

Changed lines 45-55 from:

Example: 1,234,456.00

to:

Examples: 1,234,567.00 or 1,234,567

Simple format, defined by the following EBNF:

ledgerReal :
  ( '+' | '-' )? decimalDigit+ ( '.' decimalDigits+ )?
decimalDigit :
  '0' .. '9' ;

Examples: 123456.7890 or 123456

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2010-01-14 16:09 by benjk -
Changed line 21 from:
  '.' digitGroup ( ',' digitGroup )* engScaleFactor ;
to:
  '.' digitGroup ( ',' digitGroup )* scaleFactor ;
Changed lines 24-25 from:

engScaleFactor : 

  ( '+' | '-' ) digitGroup ;
to:

scaleFactor : 

  ( '+' | '-') decimalDigit+ ;
Changed lines 30-32 from:

The numeric value of engScaleFactor must be divisible by three.

Example: 1,234.456,789E+000

to:

The numeric value of scaleFactor must be divisible by three.

Example: 1,234.456,789E+03

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2010-01-14 16:07 by benjk -
Added lines 29-30:

The numeric value of engScaleFactor must be divisible by three.

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2010-01-14 16:02 by benjk -
Changed lines 6-8 from:
  ( '+' | '-' )? decimalDigit '.' decimalDigit+ scaleFactor ;
to:
  ( '+' | '-' )? decimalDigit '.' digitGroup ( ',' digitGroup )* scaleFactor ;

digitGroup : 

  decimalDigit decimalDigit decimalDigit ;
Changed line 15 from:

Example: 1.23456789+E00

to:

Example: 1.234,567,890+E00

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2010-01-14 15:59 by benjk -
Added line 12:
Added line 27:
Added line 40:
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2010-01-14 15:58 by benjk -
Changed line 3 from:
  1. Scientific format, defined by the following EBNF:
to:

Scientific format, defined by the following EBNF:

Changed line 14 from:
  1. Engineering format, defined by the following EBNF:
to:

Engineering format, defined by the following EBNF:

Changed line 28 from:
  1. Ledger format, defined by the following EBNF:
to:

Ledger format, defined by the following EBNF:

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2010-01-14 15:58 by benjk -
Added lines 1-38:

There are multiple formats for textual representation of real numbers

  1. Scientific format, defined by the following EBNF: 
sciReal :
  ( '+' | '-' )? decimalDigit '.' decimalDigit+ scaleFactor ;
scaleFactor :
  ( '+' | '-') decimalDigit+ ;
decimalDigit :
  '0' .. '9' ;

Example: 1.23456789+E00

  1. Engineering format, defined by the following EBNF: 
engReal :
  ( '+' | '-' )? decimalDigit decimalDigit? decimalDigit? ( ',' digitGroup )*
  '.' digitGroup ( ',' digitGroup )* engScaleFactor ;
digitGroup :
  decimalDigit decimalDigit decimalDigit ;
engScaleFactor :
  ( '+' | '-' ) digitGroup ;
decimalDigit :
  '0' .. '9' ;

Example: 1,234.456,789E+000

  1. Ledger format, defined by the following EBNF: 
ledgerReal :
  ( '+' | '-' )? decimalDigit decimalDigit? decimalDigit? ( ',' digitGroup )*
  ( '.' decimalDigits+ )?
digitGroup :
  decimalDigit decimalDigit decimalDigit ;
decimalDigit :
  '0' .. '9' ;

Example: 1,234,456.00

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