MATLAB MATLAB String Operations and File I/O 2

Question 1

What is the correct way to open a file for writing in MATLAB?

Accepted Answer

fid = fopen('file.txt', 'w')

Answer

fopen opens a file and returns a file identifier; the 'w' mode opens the file for writing, creating it if it does not exist.

Question 2

Which MATLAB function replaces occurrences of a substring within a string?

Accepted Answer

strrep

Answer

strrep(str, old, new) replaces all occurrences of the old substring with the new substring in str.

Question 3

What does `fprintf(fid, '%d
', x)` do in MATLAB?

Accepted Answer

Writes formatted integer x followed by newline to the file with identifier fid

Answer

fprintf writes data to a file or screen using C-style format specifiers, with fid=1 for stdout and fid=2 for stderr.

Question 4

How do you split a string by a delimiter in MATLAB?

Accepted Answer

strsplit(str, delimiter)

Answer

strsplit splits a string at each occurrence of the specified delimiter and returns a cell array of substrings.

Question 5

Which function converts a string to lowercase in MATLAB?

Accepted Answer

lower

Answer

lower converts all uppercase letters in a string to their lowercase equivalents.

MATLAB - MATLAB Technical Computing Practice Test