Drifting Characters and Strings

Used alone in a picture, one drifting character marks the position where a special symbol or space is to be inserted. It does not affect the value's numeric interpretation. In this context, the character must appear either before or after all characters that specify digit positions.

If a series of n (n >1) drifting characters appears in a picture, the rightmost n-1 of the characters in the series also specify digit positions. If the digit is a leading zero, the leading zero is suppressed, and the leftmost character "drifts" to the right. In internal representation, the character appears either in the position of the last drifting character in the series or immediately to the left of the first significant digit, whichever comes first. In this context, the n-1 drifting characters also define a portion of the numeric precision of the picture variable, because they describe at least some positions occupied by decimal digits.

A drifting string is a series of more than one of the same drifting character. Only one drifting string can be used in a picture; other drifting characters can be used only individually to designate insertion characters, not digits.

The 'Z' and '*' characters cannot appear to the right of a drifting string.

A digit position cannot be specified to the left of a drifting string.

These rules apply to insertion characters embedded in a drifting string:

• If the drifting string contains an insertion character, the insertion character is inserted in the internal representation only if a significant digit appears to its left. In the position of the insertion character, a space appears if the leftmost significant digit is more than one position to the right; the drifting symbol appears if the next position to the right contains the leftmost significant digit.
• If the drifting string contains a 'V' character, all digit positions to the right of the 'V' (the fractional digits) must also be part of the drifting string. Insignificant fractional digits are suppressed only if all integral and fractional digits are zeros; if so, they are replaced by spaces in the internal representation. If any digit is not zero, all fractional digits appear as actual digits.
• Insertion characters that appear to the immediate right of a drifting string are considered part of the drifting string.