Convert decibels to engineering units.
g=db2eu(f)
g=db2eu(f,ref)
DB2EU converts a function from Decibels back to engineering units. REF is an optional input scalar.
If REF is not supplied, DB2EU will use the value in UserValue3 if it is non-zero. Otherwise it will use 2e-5 Pa as a reference for Pressure and Sound Pressure data types, and 1G as a reference for Acceleration. For squared OrdNumTypeQual, DB2EU uses the formula
F = REF*10^(DB/10)
For linear OrdNumTypeQual, DB2EU uses the formula
F = REF*10^(DB/20)
If the OrdinateAxisLab is set, DB2EU attempts to set the OrdNumDataType to the string specified in this attribute and will clear out this attribute (if it fails it will keep the OrdNumDataType as-is). If the OrdinateUnitsLab is set to 'DB' it will be cleared.