Find duplicate of first xx entries and average associated values

Hi all,

I have 140000x3 array data (time, lat, lon). The time column looks like [2019/12/18 上午 07:53:00]. I would like to get the mean lon and lat of several points in the same minute, like [2019/12/18 上午 07:53].

Thanks

[KSSV]

Where is your data? Is it in a excel file?

[Minh Phuong Truong]

Yes, my data is in .csv file

[Karim]

can you attach the file (use the paperclip button)

[Chris Burschyk]

You could load the data into a timetable and then use something like

T = readtimetable("YourFile.csv");
YourYear = 2019;
YourMonth = 1;
YourDay = 8;
YourHour = 8;
YourMin = 41:
mean(T{T.SYSTEMTIME.Year == YourYear & T.SYSTEMTIME.Month == YourMonth & T.SYSTEMTIME.Day == YourDay & T.SYSTEMTIME.Hour == YourHour & T.SYSTEMTIME.Minute == YourMinute, "LONGITUDE" })

Maybe not the prettiest way to do, but you could use it with a loop as well.

[Minh Phuong Truong]

a part of my data

Answer 1

[KSSV]

Read the file into MATLAB using readtable.

See to it that your dates i.e. thirs column is in datetime class. For this read about datetime, datestr, datenum.

Find the duplicates using unique. By using the indices you can get the required mean.