How to continue to loops

HI

One thing that I want to do is after first if I want to continue to sum the values in arrival in period between 100 and 200 and and other periods but I don't know how to do that and how to define 'i 'where to start after first if . I want only to sum the values in that period . first if is ok but I don't know how to continue

arrival=xlsread('tripinfo.xlsx','G:G');

depart_time=xlsread('tripinfo.xlsx','B:B');

for i = 1:1:91

if depart_time(i) < 100

mean_travel1 = sum(arrival(1:i,1));

elseif 100 < depart_time(i) & depart_time(i)< 200

mean_travel2 = sum(arrival(i,1));

elseif 200 < depart_time(i) & depart_time(i) < 300

mean_travel3 = sum(arrival(i,1));

elseif 300 < depart_time(i) & depart_time(i) < 400

mean_travel4 = sum(arrival(i,1));

elseif 400 < depart_time(i) & depart_time(i) < 500

mean_travel5 = sum(arrival(i,1));

else

mean_travel6 = sum(arrival(i,1));

end

end

Answer 1

[Amritesh]

In for loop, index = startVal:endVal is the syntax. So, you can write

for i = 1:length(depart_time)
    statements
end

Hope this resolves your doubt.

[arash rad]

thank you

but this is not my question the for loop is ok I don't know how to write sum(arrival(?????))

I don't know this

[Amritesh]

Can you give 'tripinfo.xlsx' ? And, also provide what you trying to calculate means formula or any example.

[arash rad]

This is part of tripinfo divided depart into 5 part and each part is 100s and in this period i want to sum the values of arrival time

[Amritesh]

If you are trying to store arrival time for each period and calculate mean afterwards. Then, first add that in a variable and count how many times that period occur and then divide that to get the result.

sum_travel1 = 0;
sum_travel2 = 0;
sum_travel3 = 0;
sum_travel4 = 0;
sum_travel5 = 0;
sum_travel6 = 0;
count_travel1 = 0;
count_travel2 = 0;
count_travel3 = 0;
count_travel4 = 0;
count_travel5 = 0;
count_travel6 = 0;

for i = 1:length(depart_time)
    if depart_time(i) < 100
        sum_travel1 = sum_travel1 + arrival(i);
        count_travel1 = count_travel1 + 1;
    elseif 100 < depart_time(i) & depart_time(i)< 200
        sum_travel2 = sum_travel2 + arrival(i);
        count_travel2 = count_travel2 + 1;
    elseif 200 < depart_time(i) & depart_time(i) < 300
        sum_travel3 = sum_travel3 + arrival(i);
        count_travel3 = count_travel3 + 1;
    elseif 300 < depart_time(i) & depart_time(i) < 400
        sum_travel4 = sum_travel4 + arrival(i);
        count_travel4 = count_travel4 + 1;
    elseif 400 < depart_time(i) & depart_time(i) < 500
        sum_travel5 = sum_travel5 + arrival(i);
        count_travel5 = count_travel5 + 1;
    else 
       sum_travel6 = sum_travel6 + arrival(i);
        count_travel6 = count_travel6 + 1;      
    end
end

mean_travel1 = sum_travel1/count_travel1;
mean_travel2 = sum_travel1/count_travel2;
mean_travel3 = sum_travel1/count_travel3;
mean_travel4 = sum_travel1/count_travel4;
mean_travel5 = sum_travel1/count_travel5;
mean_travel6 = sum_travel1/count_travel6;

You can also create an array sum and count of length 6 and use them as variable instead of 12 variables.

Hope this solves your doubt.

[arash rad]

thank you