Question

Python. Tuples and strings can also be sliced and concatenated.

      Let x = ['F','l','o','r','i','d','a']. How does cotDel(x, 3) compare to del x[3]?

      Let y = ('F','l','o','r','i','d','a'). How does cotDel(y, 3) compare to del y[3]?

      Let z = 'Florida'. How does cotDel(z, 3) compare to del z[3]?

      Give an explanation about what you observed. This question refers to the following statement.

Define function cotDel(s,i) that deletes the i^th item of list s, s[i]. In other words this function should do what the statement del s[i] does. Your function should use slicing and concatenation. Test your function with the list x of problem 1, deleting x[2]. Furthermore, your code should be written so that your program can be imported by other programs to make the function cotDel(s,i) available to them.

Answer 1

Hi,

Hope you are doing fine. I have coded the above question in python keeping all the conditions in mind. Now, have a look at the code of cotDel(s,i) first and then have a look at other explanations. The code snippets have also been attached to get a clear picture regarding indentation. The code has been clearly explained using comments that have been highlighted in bold.

Program:

def cotDel(s,i):
   #if i is the index of the last element then
if i==len(s)-1:
   #we slice the list s upto i and store in new
new=s[:i]
#new is returned
return new
#if i is between 0 and less than length of list s then,
elif i>=0 and i<len(s):
   #we slice s from start to i, and from i+1 to end and concatenate them to store in new
new=s[:i]+s[i+1:]
#return new
return new
#if i is an invalid index
else:
print("Invalid index")

Code snippet from editor:

• We write another file test.py to test it. Inorder to make this function available to other files we must import this using the "import" command.

Test file code:

from cotDel import cotDel

#declaring a list,tuple and a string
x = ['F','l','o','r','i','d','a']
y = ('F','l','o','r','i','d','a')
z = 'Florida'

#using cotDel
x=cotDel(x,3)
y=cotDel(y,3)
z=cotDel(z,3)

#printing results
print(x)
print(y)
print(z)

Code snippet:

Output:

Also, as asked in the question we test using only list x by deleting x[2] using cotDel.

Code:

from cotDel import cotDel

#declaring a list,tuple and a string
x = ['F','l','o','r','i','d','a']
print("Before deleting: ",x)
#calling cotDel
x=cotDel(x,2)
print("After deleting: ",x)

Code snippet:

Output:

As for the questions asked:

• Let x = ['F','l','o','r','i','d','a']. How does cotDel(x, 3) compare to del x[3]?
• Let y = ('F','l','o','r','i','d','a'). How does cotDel(y, 3) compare to del y[3]?
• Let z = 'Florida'. How does cotDel(z, 3) compare to del z[3]?

Explaining this using code in jupyter notebook as it is visually more clear to understand errors and there is line by line output:

• For list x, both the operation provide the same output.

• For tuple y, we get an error as tuple does not support the function "del". It works fine with cotDel

• For string z, again we get an error as even it does not support item deletion using del. It works fine with cotDel.

The above errors for y and z occur because del is only supported for list items and not string or tuples.