a) Write a function named 'read_line' which has one input

parameter ('specs') and one output parameter ('ret_line'). Your

function should do the following:

b) Suppose 'specs' is a struct with 4 fields: {file_dir, file_name, nlines,

my_line}. Use if?end or if?elseif?end statements to check that:
1. 'specs'isindeedastruct.
2. Thefourfieldsaboveallexist.
3. Thefields'file_dir','file_name'are(non?empty)strings

c) You should use the 'error' function to indicate an error if your checks above fail.

d) Now suppose you have a directory whose name is stored in 'specs.file_dir' which contains a file whose name is stored in 'specs.file_name'. You should assume that you have a simple text file which contains text (NOT numeric data).

e) Your function should open the file (hint: use fopen), and read 'specs.nlines' number of lines (rows) from the file into a cell array 'C'. Each element of C should contain one line from your file. You can assume that there are no errors in the parameter 'specs.nlines', that is, it cannot exceed the number of lines in your file.

f) Suppose 'specs.my_line' specifies some line number. The output parameter 'ret_line' should be set to this line (you should return a string).

g) Verify that your code works by saving some text into a file (created in notepad / textedit) and saving the file with extension '.txt'. You should attach the file (call it 'test.txt') with your code.