Creating hourly average data with geographic coordinates to produce 3D matrix

3 次查看（过去 30 天）

Aristo Pacino 2021-7-24

0
链接

此问题的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/885234-creating-hourly-average-data-with-geographic-coordinates-to-produce-3d-matrix

评论： dpb 2021-7-26

New Text Document.txt

I have 4 column matrix, which include irregular time, temperature, latitude and longitude. I want to creat 3-D matrix such that I have hourly averages of temperature within particular latitude and longitude grid. Thereby producing a 3D matrix of latitude x longitude x hourly averaged temperature.

Please find the attached dataset.

Thanks in advance!

3 个评论
显示 1更早的评论隐藏 1更早的评论

dpb 2021-7-25

Are there missing hours that would have to be interpolated/filled first (or if missing ignored)?

Aristo Pacino 2021-7-25

New Text Document.txt

Hi @KSSV, please find the attached data file with this reply. They are using hourly decimal units.

Hello @dpb, they are sometimes missing hours and can be considered as NaN. I have attached the data files with this reply .

Thanks for your interest in the my question.

请先登录，再进行评论。

请先登录，再回答此问题。

采纳的回答

dpb 2021-7-25

0
链接

此回答的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/885234-creating-hourly-average-data-with-geographic-coordinates-to-produce-3d-matrix#answer_753569

编辑：dpb 2021-7-25

在 MATLAB Online 中打开

rowfun to the rescue yet again... :)

tData=readtable();
longrid=-180:10:180;
latgrid=-90:10:90;
[~,~,~,tData.lon_g,tData.lat_g]=histcounts2(tData.lon,tData.lat,longrid,latgrid);
tGroup=rowfun(@mean,tData,'InputVariables','temp', ...
                          'GroupingVariables',{'hour','lon_g','lat_g'}, ...
                          'OutputVariableNames','temp');

produces:

>> [head(tGroup,5);tail(tGroup,5)]
ans =
  10×5 table
    hour    lon_g    lat_g    GroupCount     temp 
    ____    _____    _____    __________    ______
      0       2       14          1          89.94
      0       3        5          1          99.68
      0       3        7          1          87.31
      0       3        9          1         100.86
      0       3       15          1          71.35
     23      35       14          2          89.96
     23      35       15          1         101.81
     23      35       16          1         107.89
     23      35       18          1          101.6
     23      36        9          1           91.3
>> 

6 个评论
显示 4更早的评论隐藏 4更早的评论

Aristo Pacino 2021-7-26

Thanks @dpb, but I would like to have gridwise [latitude x longitude] correlation coefficient so as to finally have a contour plot!

dpb 2021-7-26

在 MATLAB Online 中打开

Well, that's not the Answer of the link... <VBG>

Then see

doc xcorr2

It's in Signal Processing TB

请先登录，再进行评论。

更多回答（1 个）

KSSV 2021-7-25

0
链接

此回答的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/885234-creating-hourly-average-data-with-geographic-coordinates-to-produce-3d-matrix#answer_753529

在 MATLAB Online 中打开

T = readtable('New Text document.txt') ; 
t = T.hour ; 
lon = T.lon ; 
lat = T.lat ;
temp = T.temp ; 
[c,ia,ib] = unique(t) ;
n = length(c) ; 
iwant = cell(n,1) ; 
for i = 1:n
    iwant{i} = [t(ib==i) lon(ib==i) lat(ib==i) temp(ib==i)] ; 
end

1 个评论
显示 -1更早的评论隐藏 -1更早的评论

Aristo Pacino 2021-7-25

Hi @KSSV, thank you very much but this is not what I desired. Sorry, I might be unclear but I wanted something for e.g within the longitude [-180 -170] and latitude [0 10] grid, I wanted the temperature to be sampled every one hour. So that I have some what like n x m x z matrix, where n is longitudinal size with grid size of 10 degrees, m is latitudinal size with grid size every 10 degrees and z is temperature size at every one hour sampling frequency.

I would be very happy if you could help me further but much thanks for your effort.

Cheers

请先登录，再进行评论。

请先登录，再回答此问题。