A format specification used for definition of templates in the Custom ASCII protocol consists of three optional and one required fields.
[PDG:flags] [PDG:width] [PDG:.precision] type
Each field of the format specification is a character or a number signifying a format option. The simplest format specification contains only a type character (e.g. s or d). The optional fields for flags, width and precision control other aspects of the formatting, as follows:
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Signed value having the form [ PDG: – ]d.dddd e [PDG:sign]dd[PDG:d] where d is a single decimal digit, dddd is one or more decimal digits, dd[PDG:d] is two or three decimal digits depending on the output format and size of the exponent, and sign is + or --.
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Signed value having the form [ PDG: – ]dddd.dddd, where dddd is one or more decimal digits. The number of digits before the decimal point depends on the magnitude of the number, and the number of digits after the decimal point depends on the precision.
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NOTE: The use of any other type characters should not be attempted.