Printing specific parts of a string in python [duplicate]

Answer 1

I'll try to guess expected result:

def printThree(str):
    for i in range(0, len(str), 3):
        print str[i:i+3]

Output

>>> printThree("somestring")
som
est
rin
g

Answer 2

Use slicing:

def PrintThree(string):
    return string[:3]

This runs as:

>>> PrintThree('abcde')
'abc'
>>> PrintThree('hello there')
'hel'
>>> PrintThree('this works!')
'thi'
>>> PrintThree('hi')
'hi'
>>> 

In the last example, if the length is less than 3, it will print the entire string.

string[:3] is the same as string[0:3], in that it gets the first three characters of any string. As this is a one liner, I would avoid calling a function for it, a lot of cuntions gets confusing after some time:

>>> mystring = 'Hello World!'
>>> mystring[:3]
'Hel'
>>> mystring[0:3]
'Hel'
>>> mystring[4:]
'o World!'
>>> mystring[4:len(mystring)-1]
'o World'
>>> mystring[4:7]
'o W'
>>> 

Or, if you want to print every three characters in the string, use the following code:

>>> def PrintThree(string):
...     string = [string[i:i+3] for i in range(0, len(string), 3)]
...     for k in string:
...             print k
... 
>>> PrintThree('Thisprintseverythreecharacters')
Thi
spr
int
sev
ery
thr
eec
har
act
ers
>>> 

This uses list comprehension to split the string for every 3 characters. It then uses a for statement to print each item in the list.