E,N coordinates convert to GB OS National Grid Sheet Coordinates

Anybody know where i can get my hands on a conversion function to
convert regular British National Grid coordinates (6 digit easting and
northing coordinates) to OS NGCs (e.g. TL5467 6723)?

Regards,
AndyB

Andy,

This is a MapBasic function (Mapinfo scripting language) that I've
written to do what you want:
<-------
'// function to return the tile letters (ie SU) given the x,y coords
Function GetTileLetters(ByVal szXcoord As Float, ByVal szYcoord As
Float) as String
Dim x, y As Float
Dim FirstLet, SecondLet As String
szXcoord = szXcoord + 1000000
szYcoord = szYcoord + 500000

'// do the 500km squares first
x = (szXcoord/500000) MOD 5
y = (szYcoord/500000) MOD 5

FirstLet = CHR$(ASC("A")+(x+5*(4-y))+1)
Else
FirstLet = CHR$(ASC("A")+(x+5*(4-y)))
End If

'// do the 100km squarea
x = (szXcoord/100000) MOD 5
y = (szYcoord/100000) MOD 5

SecondLet = CHR$(ASC("A")+(x+5*(4-y))+1)
Else
SecondLet = CHR$(ASC("A")+(x+5*(4-y)))
End If

GetTileLetters = FirstLet + SecondLet

End Function
ASC() returns the ASCII character code - ASC("A") = 65
CHR$() returns the character-string of the corresponding ASCII code -
CHR$(65) = "A"

I got it from somewhere on the web but can't remember where.

Let me know if you need anything clarifying.

Gref

Thanks Greg,
It sounds perfect.

greg.driver@btinternet.com wrote in message