Required array is dependent on other arrays

The overall scores out of 100 students is included in the ascii file Scores.txt. The cut-off ratios for the letter grades are

Percentage, % Final Grade Letter

90 < Grade = A

80 < Grade < 90 = B

70 <= Grade < 80 = C

60 < Grade < 70 = D

Grade < 60 = F

Write a computer program in a script file that

a.Import the data in the text file Scores.txt using the load () command/function and assign it to a variable name Scores.

b.Assign the 1st column of Scores variable to ID and the second column to OG.

c.Determines the average score (S_avg) in the class. You can use the MATLAB built-in functions mean ().

d.Determines the number of students above the average (N_aavg). You can use the MATLAB built-in functions sum (). Please see the help of the functions sum() and mean () before using them.

e.Determine the number of students within +5% of the average (N_5avq).

f.Determines the number of students in each letter grade (N_A, N_B, N_C, N_D, N_F).

g.Determines the ID of students in each letter grade (ID_A, ID_B, IDC, ID_D, ID_F).

%<MY CODE WAS HERE>

HELP with:

The code below is what I have written so far, and have attached the txt file required.

I need help with part g, where it needs to create an array with the IDs of the students of that certain threshold.

when I run the code, it returns a single value rather than an array of required IDs.

Also, is there a better way to do parts d and e using sum() and mean() functions?

Answer 1

[C B]

ID_A = [];ID_B = [];ID_C = [];ID_D = []; ID_F = [];
for x = 1:size(Scores,1)
    if OG(x)>90
     ID_A(end+1) = ID(x);
    elseif (OG(x)>=80) && (OG(x)<90)
     ID_B(end+1) = ID(x);
    elseif (OG(x)>=70) && (OG(x)<80)
     ID_C(end+1) = ID(x);
    elseif (OG(x)>=60) && (OG(x)<70)
     ID_D(end+1) = ID(x);
    elseif (OG(x)<60)
     ID_F(end+1) = ID(x);
    end
end

Also every for loop can be more generic by using size instead of hard coded 100

size(Scores,1)

[Humza Khan]

Thank you!