Writes the {@link PDMDecimal} as 9 bytes into the byte array at position

C# |
public virtual int writeDecimal( byte[] ba, int pos, PDMDecimal dec )

- ba (array< Byte >[]()[])
- the byte array
- pos (Int32)
- the starting position
- dec (PDMDecimal)
- the PDMDecimal to write

the updated position in the byte array after the write