Get vector position for specific values

Hi,

I have two vectors, one of them has a large data values, the other has some values that I want to find in the first one to get the position.

    Trip_dst;%%This vector has the complete data
    Cumm_Trip_Dist;%%%This vector has specific values that I want to find in "Trip_dst" vector
%%I'm trying to use this to find the first value, which difference is not more than 0,05
Cumm_Trip_DistLength = length(Cumm_Trip_Dist);%%Get the lenght for the data required
for AP = 1:Cumm_Trip_DistLength
    AC = find(Trip_dst < (Cumm_Trip_Dist(AP)+.05)& Trip_dst > Cumm_Trip_Dist(AP));
    AB(AP,1) = AC(1);%%Get the first value(the nearest), AB is my vector with the positions 
end

However as not all data that I'm looking for from the second vector is in the first one I got the next message:

"Attempted to access AC(1); index out of bounds because numel(AC)=0".

What can I do to just skip this value not founded and try to find the next one?

Hope you can help me, maybe this has a really easy solution.

Regards

Answer 1

[Azzi Abdelmalek]

for AP = 1:Cumm_Trip_DistLength
  AC = find(Trip_dst < (Cumm_Trip_Dist(AP)+.05)& Trip_dst > Cumm_Trip_Dist(AP));
  if ~isempty(AC)
      AB(AP,1) = AC(1);%%Get the first value(the nearest), AB is my vector with the positions 
  else
      AB(AP,1)=nan   
  end
end

%If you want to find the first value that meets the criterion, look at this example

A=[1 2 3 2 4 5 2]
idx=find(A==2,1)

[Luis Lopez]

Great, it Works!!

Answer 2

[Star Strider]

I don’t have your data, so I’m guessing here with created data.

See if this does what you want:

Cumm_TripDist = randi(20, 1, 10);
TripDist = randi(99, 1, 100);
for k1 = 1:length(Cumm_TripDist)
    [~,AB(k1)] = ismembertol(Cumm_TripDist(k1), TripDist, 0.05);
end