Why reading and writing data is fundamental in MATLAB - Test Your Understanding

Practice - 5 Tasks

1fill in blank

easy

Complete the code to read data from a file named 'data.txt'.

MATLAB

fileID = fopen('data.txt', '[1]');

Drag options to blanks, or click blank then click option'

Ar

Bx

Ca

Dw

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'w' which opens the file for writing and erases content.

Using 'a' which opens the file for appending data.

Use 'r' to open a file for reading in MATLAB.

2fill in blank

medium

Complete the code to write the variable 'data' to a file.

MATLAB

fileID = fopen('output.txt', '[1]');

Drag options to blanks, or click blank then click option'

Ar+

Br

Cw

Da

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'r' which only allows reading.

Using 'a' which appends instead of overwriting.

Use 'w' to open a file for writing, which creates or overwrites the file.

3fill in blank

hard

Fix the error in the code to properly close the file after reading.

MATLAB

fileID = fopen('data.txt', 'r');
data = fscanf(fileID, '%f');
[1](fileID);

Drag options to blanks, or click blank then click option'

Afclose

Bfopen

Copen

Dfcloseall

Attempts:

3 left

💡 Hint

Common Mistakes

Using open or fopen again instead of closing.

Using fcloseall which closes all files, not just this one.

Use fclose(fileID) to close the file and free system resources.

4fill in blank

hard

Fill both blanks to read numeric data from a file and store it in 'data'.

MATLAB

fileID = fopen('numbers.txt', '[1]');
data = fscanf(fileID, '[2]');
fclose(fileID);

Drag options to blanks, or click blank then click option'

Ar

Bw

C%f

D%s

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'w' which opens for writing, not reading.

Using '%s' which reads strings, not numbers.

Open the file for reading with 'r' and use '%f' to read floating-point numbers.

5fill in blank

hard

Fill all three blanks to write a matrix to a file with formatted output.

MATLAB

fileID = fopen('matrix.txt', '[1]');
for i = 1:size(matrix, 1)
    fprintf(fileID, [2], matrix(i, :));
end
fclose([3]);

Drag options to blanks, or click blank then click option'

Aw

B'%d %d %d\n'

CfileID

D'%f %f %f\n'

Attempts:

3 left

💡 Hint

Common Mistakes

Using '%d' which formats integers instead of floats.

Forgetting to close the file or using wrong variable in fclose.

Open the file for writing with 'w', use '%f %f %f\n' to format floats, and close with fclose(fileID).