First name or whole name to be used?

[Yondi]

I have been practising on numerology but am confused about how some books use first name in calculation, whereas others use full name.  
Can anyone advise me?  Will really appreciate it.

[rasp34]

Hi Yondi from what I've learned you can do a reading using your first name and date of birth but to get a more accurate reading you should use your full birth name.

[s.v.kuppuswamy]

Dear yondi,
Use of your name anywhere requires the place of your use. ie is it office or home or friendly chat?

In office use it is always the first name
In home it is the oet name or last name
In friends area it is last name, The use of the name depends upon the place it is used,
ok
Regads
svk