I want to match multi-filed's data in two structure data.

I have two stuctures data showing as two pictures,and I want to find the data that meets the conditions to match. Using the loop is very slow. Please give me some better advice.Thanks.

if true
   for i= 1:length(ap.date)
   dnb = datevec(ap.date(i));
   lonb=ap.lon(i);
   latb=ap.lat(i);
     for j=1:length(ad.date)
        dna = datevec(ad.date(j));
          lona=ad.lon(j);
          lata=ad.lat(j);
        difftime=fix(etime(dna,dnb)/3600);
        difflon=lonb-lona;
        difflat=latb-lata;
        if (difftime>=-0.05 & difftime <=0.05 & difflon>=-0.001 & difflon <=0.001 & difflat>=-0.001 & difflat <=0.001)==1
                temp=[i j];  w=[w;temp];
                re_data.date(i,1)=ap.date(i);
                re_data.lon(i,1)=ap.lon(i);
                re_data.lat(i,1)=ap.lat(i);
                re_data.date_ad(i,1)=ad.date(j);
                re_data.lon_ad(i,1)=ad.lon(j);
                re_data.lat_ad(i,1)=ad.lat(j);
                re_data.cruise_ad(i,1)=ad.cruise(j);
                re_data.depth_ad(i,1)=ad.depth(j);

          elseif  difftime>=-0.05 & difftime <=0.05 & difflon>=-0.001 & difflon <=0.001 & difflat>=-0.001 & difflat <=0.001
                  re_data.date(i,1)=ap.date(i);
                  re_data.lon(i,1)=ap.lon(i);
                  re_data.lat(i,1)=ap.lat(i);
                  re_data.date_ad(i,1)={-999};
                  re_data.lon_ad(i,1)=-999;
                  re_data.lat_ad(i,1)=-999;
                  re_data.cruise_ad(i,1)={-999};
                  re_data.depth_ad(i,1)=-999;

           end
       end
 end

[xszm]

I have two stuctures data showing as two pictures,and I want to find the data that meets the conditions to match. Using the loop is very slow. Please give me some better advice.Thanks.

[Guillaume]

What format is the time in the cell arrays, datestr?

What should happen if there is more than one match in ad for a single ap? Or is it guaranteed that it never happens?

Any reason you're using old matlab time functions instead of modern datetime? Which version are you using?

[xszm]

1. yyyy/mm/dd hh:mm:ss 2. yes.I will handle after this loop 3. I used 2017a maltab.