isSigned method
Implementation
bool isSigned({int? subfieldIndex, String? subfieldName}) {
Subfield? subfield;
if (subfieldIndex != null) {
subfield = getSubfieldByIndex(subfieldIndex);
} else if (subfieldName != null) {
subfield = getSubfieldByName(subfieldName);
}
final int t = subfield == null ? type : subfield.type;
return Fit.baseType[t & Fit.baseTypeNumMask].isSigned;
}