find maximum value for each year in a 2 columns array

2020 4 16
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I have an array with two columns, column one year (1975-2020) and column two discharge values. I need to find the maximum discharge amount for each year and have them saved in another matrix.
Can you please help me with this?
input:
1975 200
1975 85
.
.
.
2002 110
2002 95
2002 32
...
2020 120
...
desired output
1975 200
...
2002 110
...
2020 120

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Tommy
Tommy 2020-4-16

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Try this:
[G, y] = findgroups(input(:,1));
output = [y splitapply(@max, input(:,2), G)];

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Mahtab Moalemi
Mahtab Moalemi 2020-4-16
Thanks but it gives me this error:
Error using splitapply (line 99)
The data variables must have the same number of rows as the vector of group numbers. The group number
vector has 46 row(s), and data variable 1 has 934768 row(s).
Tommy
Tommy 2020-4-16
Do you mind posting the code you ran which gave you this error?
Mahtab Moalemi
Mahtab Moalemi 2020-4-16
[years,groups] = findgroups(year_Q(:,1));
>> output = [years splitapply(@max, year_Q(:,2), groups)];
Tommy
Tommy 2020-4-16
编辑：Tommy 2020-4-16
Switch the outputs.
[groups, years] = findgroups(year_Q(:,1));
>> output = [years splitapply(@max, year_Q(:,2), groups)];

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