How do I calculate distances between multiple points on a map using a loop.

Hi!

I have worked out how to find out the distance between just 2 coordinates using the mapping toolbox as shown:

[arclen, az] = distance([40.333, -10.036 ], [40.333, -9.46]);

km = deg2km(arclen);

display(km)

This is what I get:

>> stationdist

km =

   48.8236

However, I have 32 latitude and longitude pairs. These pairings form a path across the North Atlantic, and I need to find the distance between each latitude&longitude pair.

I need to have Matlab spew out all these distances in between station points, and also each new distance needs to be a sum of previous distances.

I am aware I need to use a loop to do this and call in an array of the lat&lon points.

I want it to look like this, assuming each station is calculated to be roughly 50km apart:

>> stationdist

km =

   48.8236
   104.2764
   150.3973
   204.9521

How would I do this? Any hints or words would be much appreciated.

Thanks :)

Charlie

Answer 1

[KSSV]

If (x,y) are your column data. To get the distance between successive points use:

dx = diff(x) ; dy = diff(y) ;
d = sqrt(dx.^2+dy.^2) ;
thesum = cumsum(d) ;

Also have a look on pdist, pdist2.

[Charlie Hillary]

Hi,

I have the calculation for distance, and can do so, but only for individual points. How would I loop this for multiple values?

Charlie :)

[KSSV]

Run a loop....

I have shown you the distance finding of multiple successive points arrange in a m*2 array.

Also mentioned to read about pdist, pdist2.

[Charlie Hillary]

Ok will do!