icd9DropLeadingZeroes: drop zero padding from decimal ICD-9 code.
In jackwasey/icd9: Tools for Working with ICD-9 Codes, and Finding Comorbidities

Description Usage Arguments Value See Also

decimal form ICD-9 codes are not ambiguous if the leading zeroes are dropped. Some short-form ICD-9 codes would not be ambiguous, e.g. "1" but many would be problematic. This is the inverse of icd9AddLeadingZeroesDecimal.

Invalid codes have no guaranteed result, and may give NA, or a (possibly valid) code in repsonse.

icd9DropLeadingZeroes(icd9, isShort)

icd9DropLeadingZeroesDecimal(icd9Decimal)

icd9DropLeadingZeroesShort(icd9Short)

icd9DropLeadingZeroesMajor(major)

`icd9`	is a character vector or factor of ICD-9 codes. If fewer than five characters is given in a code, then the digits are greedily assigned to hundreds, then tens, then units, before the decimal parts. E.g. "10" becomes "010", not "0010".
`icd9Decimal`	character vector of ICD-9 codes. If fewer than five characters is given in a code, then the digits are greedily assigned to hundreds, then tens, then units, before the decimal parts. E.g. "10" becomes "010", not "0010"
`icd9Short`	is a character vector of ICD-9 codes. If fewer than five characters is given in a code, then the digits are greedily assigned to hundreds, then tens, then units, before the decimal parts. E.g. "10" becomes "010", not "0010"