How to SUMIF similar to Excel

Hi I have a table with the following values and want to do SUMIF similar to excel and save data to a new table (Table T below). I tried to get all power values that occur at the same time to be summed, so that I can plot one curve. Not sure where this is going wrong.

DateTime Power

____ _____

Feb 1 2022 01:00 4

Feb 1 2022 02:00 5

Feb 1 2022 02:00 2

Feb 1 2022 03:00 1

Desired Result:

DateTime Power

____ _____

Feb 1 2022 01:00 4

Feb 1 2022 02:00 7

Feb 1 2022 03:00 1

t1 = datetime(2022,02,01,0,1,0);
t2 = datetime(2022,02,01,0,5,0);

totalminutes = minutes(t2-t1);
t = (t1:minutes(1):t2);

    for i = 1:totalminutes;

        if T.DateTime == t(1,i);
            
            R = table(T.DateTime,sum(T.Power));
            
        else
        end

Answer 1

[Stephen23]

"Not sure where this is going wrong."

Reinventing the wheel by writing lots of loops, and ignoring the inbuilt tools.

dt = datetime(2022,2,1,[1;2;2;3],0,0);
pw = [4;5;2;1];
tbl = table(dt,pw)

tbl = 4×2 table
             dt             pw
    ____________________    __

    01-Feb-2022 01:00:00    4 
    01-Feb-2022 02:00:00    5 
    01-Feb-2022 02:00:00    2 
    01-Feb-2022 03:00:00    1 

out = groupsummary(tbl,"dt","sum")

out = 3×3 table
             dt             GroupCount    sum_pw
    ____________________    __________    ______

    01-Feb-2022 01:00:00        1           4   
    01-Feb-2022 02:00:00        2           7   
    01-Feb-2022 03:00:00        1           1