Eastings & Northings

  • Thread starter Thread starter Michael
  • Start date Start date
M

Michael

Hi All
I have about 70 sets of Easting & Northing Co-Ordinates
I want to be able to use one set as my base Co-Ords, in
say A1 & B1.Then when I type in another set in say A2 &
B2, I would like to find the distance and angle
Any help would be appreciated

Regards
Michael
 
Takes me back to O Level Maths. Is that what this is for? ;)

By Pythagoras, the distance P1P2 can be calculated as :

=SQRT((A2-A1)^2+(B2-B1)^2)

The angle is more tricky. I need to play for a bit.
 
Vaughan said:
OK, well my maths is letting me down a bit, but you will be looking
Click to expand...
to find the arctangent of (A2-A1)/(B2-B1) and then interpreting the
result as a bearing.
In excel the arctangent can be found using the ATAN() function,
Click to expand...
giving you a result in radians. To turn it into degrees try:
=DEGREES(ATAN((A2-A1)/(B2-B1)))

This then needs to be turned into a bearing from North I guess. I
Click to expand...
don't know if there is a clever way, but basically:
if A2 > A1 and B2 > B1 the bearing is between 0 and 90 degrees
if A2 > A1 and B2 < B1 the bearing is between 90 and 180 degrees
if A2 < A1 and B2 < B1 the bearing is between 180 and 270 degrees
if A2 < A1 and B2 > B1 the bearing is between 270 and 360 degrees

... so you could create a formula that would test for these
Click to expand...
conditions and add the appropriate number of quadrants.
Note also that if B1 = B2, the above will returna #DIV/0! error, so
Click to expand...
you will have to test for that too.
Sorry, don't have the energy to try to put all that into a formula, but maybe it will help you.
Click to expand...

Have a look at ATAN2 using (En-E0), (Nn-N0) assuming (E0, N0) is your
origin point.

Best wishes,
 
Thanks guys
You're right, it is "O" level Maths. Trouble is I did that
30 years ago.
And you have refreshed my memory.
Thanks for the help

Regards
Michael
-----Original Message-----
OK, well my maths is letting me down a bit, but you will
Click to expand...
be looking to find the arctangent of (A2-A1)/(B2-B1) and
then interpreting the result as a bearing.
In excel the arctangent can be found using the ATAN()
Click to expand...
function, giving you a result in radians. To turn it into
degrees try:
=DEGREES(ATAN((A2-A1)/(B2-B1)))

This then needs to be turned into a bearing from North I
Click to expand...
guess. I don't know if there is a clever way, but
basically:
if A2 > A1 and B2 > B1 the bearing is between 0 and 90 degrees
if A2 > A1 and B2 < B1 the bearing is between 90 and 180 degrees
if A2 < A1 and B2 < B1 the bearing is between 180 and 270 degrees
if A2 < A1 and B2 > B1 the bearing is between 270 and 360 degrees

.... so you could create a formula that would test for
Click to expand...
these conditions and add the appropriate number of
quadrants.
Note also that if B1 = B2, the above will returna #DIV/0!
Click to expand...
error, so you will have to test for that too.
Sorry, don't have the energy to try to put all that into
Click to expand...
a formula, but maybe it will help you.
 
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