Loop to carry out calculation for pairs 1 and 2, then pairs 2 and 3 and so on.

BOB (view profile)

on 21 Aug 2018
Latest activity Commented on by Torsten

on 21 Aug 2018

Torsten (view profile)

Hi,
I have two 8x1 matrices. One matrix is list of longitude coordinates (Final_Longitude_Values). The other matrix is the corresponding latitude coordinates (Final_Latitude_Values).
I want to calculate the distance between the first pair and the second pair, and then the second pair and the third pair, and so on until I have come to the end of each matrix.
I have written the following code in an attempt to automate this process:
{for j = 1:length(Final_Latitude_Values)
latlon1=[(Final_Latitude_Values(j)) (Final_Longitude_Values(j))];
latlon2=[(Final_Latitude_Values(j+1) (Final_Longitude_Values(j+1))];
end
[d1km d2km]=distance(latlon1,latlon2);
Segment_Distance = d2km}
However, the index exceeds the matrix dimensions, and I can't seem to figure out how to work around this issue. If anyone could correct my code it would be much appreciate.
Thanks

Torsten (view profile)

on 21 Aug 2018

Use
for j = 1:length(Final_Latitude_Values)-1
for j = 1:length(Final_Latitude_Values)
Best wishes
Torsten.

Fangjun Jiang (view profile)

on 21 Aug 2018

You have 8 locations thus 7 distances. When j is 8, Final_Latitude_Values(j+1) exceeds the matrix dimension.
Change the for-loop to
for j = 1:length(Final_Latitude_Values)-1

BOB (view profile)

on 21 Aug 2018

Cheers folks! Works great.

Torsten

Torsten (view profile)

on 21 Aug 2018
I don't know if this is intended, but note that you only calculate the distance between the last two components of the vectors, namely
[(Final_Latitude_Values(j)) (Final_Longitude_Values(j))]
and
[(Final_Latitude_Values(j+1)) (Final_Longitude_Values(j+1))]
for
j = length(Final_Latitude_Values)-1.