Help with my code (simple)

[ozs]

Hi everyone.
Im trying to make a function that blend randomly the words in a sentence.
Made some checks with print command... ignore it.
Im quite new with python so feel free to advice me what ive done wrong.

Here is my code; it seems like ive done it ok, but something go wrong when I run it :/

import random def BlendString(): string = input ("Enter a sentence: \n") s = string.split() i=0 newstring = s print (newstring) rand = random.sample(range(0,len(s)),len(s)) print (rand) while len(s)-1 > i: newstring[i] = s[rand[i]] print (newstring) i+=1 BlendString()

[j.crater]

Can you provide the output you get and explain what is wrong with it compared to what you would like the result to be?

[ozs]

sure.

here is the code(change the while loop to len(s) > i without the minus(-)) :

import random def BlendString(): string = input ("Enter a sentence: ") s = string.split() i=0 newstring = s print ("this is the string Ive entered " +str(newstring)) rand = random.sample(range(0,len(s)),len(s)) print ("\n\nthis is the random sequance that should be: " + str(rand)+"\n") while len(s) > i: newstring[i] = s[rand[i]] print (newstring) i+=1 BlendString()

ive entered - "0 1 2 3" as a string to be blend, so that the rand will actually show the final sequence.
here is the output:

Output:
Enter a sentence: 0 1 2 3 this is the string Ive entered ['0', '1', '2', '3'] this is the random sequance that should be: [1, 2, 3, 0] ['1', '1', '2', '3'] ['1', '2', '2', '3'] ['1', '2', '3', '3'] ['1', '2', '3', '1'] 

The problem here is the last string(digit in this case...) that dont turn to 0 as expected.

I wish i explained myself clear, english isnt my native :)
Thanks!

[ThiefOfTime]

The main Problem here is, that the list you save in newstring is not copied. The variable s and newstring are holding the same reference:

def blend(): string = input("Enter: ") s = string.split() newstring = s#list(s) rand = random.sample(range(0, len(s)), len(s)) print rand for i, ind in enumerate(rand): print "######## %i Try ########" % (i+1) print "newstring_list: %s"%str(newstring) print "old_string_list %s"%str(s) newstring[i] = s[ind] return newstring In [2]: blend() Enter: "1 2 3 4" [3, 2, 0, 1] ######## 1 Try ######## newstring_list: ['1', '2', '3', '4'] old_string_list ['1', '2', '3', '4'] ######## 2 Try ######## newstring_list: ['4', '2', '3', '4'] old_string_list ['4', '2', '3', '4'] ######## 3 Try ######## newstring_list: ['4', '3', '3', '4'] old_string_list ['4', '3', '3', '4'] ######## 4 Try ######## newstring_list: ['4', '3', '4', '4'] old_string_list ['4', '3', '4', '4'] Out[2]: ['4', '3', '4', '3']

So while copying you already altered the original list. Make a copy of your list by using list:

def blend(): string = input("Enter: ") s = string.split() newstring = list(s) rand = random.sample(range(0, len(s)), len(s)) for i, ind in enumerate(rand): newstring[i] = s[ind] return newstring

or by having an empty list:

def blend(): string = input("Enter: ") s = string.split() newstring = [] rand = random.sample(range(0, len(s)), len(s)) for ind in rand: newstring.append(s[ind]) return newstring

[ozs]

OK thank you!

Just to make sure - enumerate is equal to i+=1, right?

---

Just exposed to a very simple solution I wanted to share:

random.shuffle(newstring)

Make the code way easier.

[ThiefOfTime]

That's right, random.shuffle is way easier, unfortunately I forgot about it, so I didn't mentioned it before. sry about that :D
enumerate takes a list you want to iterate through and gives you the value hold at a position and its corresponding index.
so if you have a list like list_test = ["a", "b", "c", "d"] and you call enumerate(list_test) it makes an iterable enumerate object giving you values like you would get with [(0,"a"), (1, "b"), (2, "c"), (3, "d")]. It is just a simple trick to get the values and the indices at the same time while iterating over a list :)