Need help in average velocity (Si-Sf)/(Ti-Tf) code. without using in built functions

I need help in this problem. This is the first time using A programming software and its a challenge. given a set of data on excel in two columns, time and distance, they are not sorted and have 4000 rows. The program needs to just calculate the average velocity (Si-Sf/Ti-Tf) from the excel columns and give one final answer and display it. Thank You in advance.

Here is a what i did, although it's not correct and i don't know how to proceed.

clc,clear
filename = 'LoopingData.xlsx';
[rows, columns] = size(filename);
for col = 1 : columns
  theSum = 0;
  for row = 1 : rows
    theSum = theSum + filename(row, col);
  end
  % Now get the mean over all values in this column.
 columnMeans(col) = theSum / rows;
end
disp (columnMeans)
columnB = xlsread(filename,'B:B')
columnA = xlsread(filename,'A:A')

Answer 1

[Walter Roberson]

filename = 'LoopingData.xlsx';

creates filename as a row vector of characters.

    theSum = theSum + filename(row, col);

would access specific characters in the row vector, and would never attempt to look at the content of the file.

You need to xlsread() the file and process that, such as

num = xlsread(filename);

and then iterate over the contents of num

[Diana Hopps]

I tried to use that before but i still can't calculate the velocity from the excel columns. I just need the formula to read the two columns i will do the rest

[Walter Roberson]

num = xlsread(filename);
columnA = num(:,1);
columnB = num(:,2);

Answer 2

[Diana Hopps]

i tried to use that before, but still i can't solve the average