Find lower query points compared to the Reference vector

Question

Ganesh Naik 2022-8-6

0
链接

此问题的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/1775030-find-lower-query-points-compared-to-the-reference-vector

评论： Ganesh Naik 2022-8-8

data.mat

Hi all, I have two vectors, one is "Beg_Data" which has 19 values and I have another reference vector "Beg_In_Ex" which contains 1239 values (Data attached). I am computing a new vector "End_Cycle" same size (19 values) that of "Beg_Data" vector based on the nearest neighbour search. I would like to achieve the results of "End_Cycle" values lower than that of corresponding values that of "Beg_Data". However, using the method that I have attempted I found some values are always higher than that of the "Beg_Data" values. As you can see I want the difference to be always positive (End_Cycle<Beg_Data). Any help in this regard is highly appreciated.

load data.mat;
End_Cycle = dsearchn(Beg_In_Ex',Beg_Data);
End_Cycle = Beg_In_Ex(End_Cycle)';
Start_Stop = [End_Cycle Beg_Data]
Start_Stop = 19×2
1.0e+06 *

    0.0746    0.0761
    0.2064    0.2047
    0.2327    0.2346
    0.4144    0.4130
    0.5276    0.5263
    0.6324    0.6329
    0.8096    0.8088
    0.9534    0.9518
    0.9722    0.9702
    0.9777    0.9760
Difference = Start_Stop(:,2)-Start_Stop(:,1)
Difference = 19×1
1.0e+03 *

    1.4242
   -1.6832
    1.9540
   -1.3347
   -1.3141
    0.4402
   -0.7642
   -1.6077
   -2.0212
   -1.6784

3 个评论
显示 1更早的评论隐藏 1更早的评论

Voss 2022-8-7

在 MATLAB Online 中打开

Just change the definition of idx(ii):

idx(ii) = find(Beg_In_Ex >= Beg_Data(ii),1);

Ganesh Naik 2022-8-8

Dear Voss, thanks, this is perfect and it works.

Kind regards

请先登录，再进行评论。

请先登录，再回答此问题。

Answer 1

Voss 2022-8-6

0
链接

此回答的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/1775030-find-lower-query-points-compared-to-the-reference-vector#answer_1022140

在 MATLAB Online 中打开

data.mat

load data.mat;
idx = zeros(size(Beg_Data));
for ii = 1:numel(Beg_Data)
    idx(ii) = find(Beg_In_Ex <= Beg_Data(ii),1,'last');
end
End_Cycle = Beg_In_Ex(idx).';
Start_Stop = [End_Cycle Beg_Data]
Start_Stop = 19×2
1.0e+06 *

    0.0746    0.0761
    0.2016    0.2047
    0.2327    0.2346
    0.4108    0.4130
    0.5245    0.5263
    0.6324    0.6329
    0.8071    0.8088
    0.9495    0.9518
    0.9676    0.9702
    0.9732    0.9760
Difference = Start_Stop(:,2)-Start_Stop(:,1)
Difference = 19×1
1.0e+03 *

    1.4242
    3.0948
    1.9540
    2.2663
    1.7939
    0.4402
    1.6808
    2.2943
    2.5998
    2.8346