I'm sure this is covered in plenty of places, but I don't know the exact name of the action I'm trying to do so I can't really look it up. I've been reading an official Python book for 30 minutes trying to find out how to do this.
Problem: I need to put a string in a certain length "field".
For example, if the name field was 15 characters long, and my name was John, I would get "John" followed by 11 spaces to create the 15 character field.
I need this to work for any string put in for the variable "name".
I know it will likely be some form of formatting, but I can't find the exact way to do this. Help would be appreciated.
This is super simple with format:
>>> a = "John"
>>> "{:<15}".format(a)
'John '
You can use the ljust method on strings.
>>> name = 'John'
>>> name.ljust(15)
'John '
Note that if the name is longer than 15 characters, ljust won't truncate it. If you want to end up with exactly 15 characters, you can slice the resulting string:
>>> name.ljust(15)[:15]
If you have python version 3.6 or higher you can use f strings
>>> string = "John"
>>> f"{string:<15}"
'John '
Or if you'd like it to the left
>>> f"{string:>15}"
' John'
Centered
>>> f"{string:^15}"
' John '
For more variations, feel free to check out the docs: https://docs.python.org/3/library/string.html#format-string-syntax
You can use rjust and ljust functions to add specific characters before or after a string to reach a specific length.
The first parameter those methods is the total character number after transforming the string.
Right justified (add to the left)
numStr = '69'
numStr = numStr.rjust(5, '*')
The result is ***69
Left justified (add to the right)
And for the left:
numStr = '69'
numStr = numStr.ljust(3, '#')
The result will be 69#
Fill with Leading Zeros
Also to add zeros you can simply use:
numstr.zfill(8)
Which gives you 00000069 as the result.
string = ""
name = raw_input() #The value at the field
length = input() #the length of the field
string += name
string += " "*(length-len(name)) # Add extra spaces
This will add the number of spaces needed, provided the field has length >= the length of the name provided
name = "John" // your variable
result = (name+" ")[:15] # this adds 15 spaces to the "name"
# but cuts it at 15 characters
I know this is a bit of an old question, but I've ended up making my own little class for it.
Might be useful to someone so I'll stick it up. I used a class variable, which is inherently persistent, to ensure sufficient whitespace was added to clear any old lines. See below:
2021-03-02 update: Improved a bit - when working through a large codebase, you know whether the line you are writing is one you care about or not, but you don't know what was previously written to the console and whether you want to retain it.
This update takes care of that, a class variable you update when writing to the console keeps track of whether the line you are currently writing is one you want to keep, or allow overwriting later on.
class consolePrinter():
'''
Class to write to the console
Objective is to make it easy to write to console, with user able to
overwrite previous line (or not)
'''
# -------------------------------------------------------------------------
#Class variables
stringLen = 0
overwriteLine = False
# -------------------------------------------------------------------------
# -------------------------------------------------------------------------
def writeline(stringIn, overwriteThisLine=False):
import sys
#Get length of stringIn and update stringLen if needed
if len(stringIn) > consolePrinter.stringLen:
consolePrinter.stringLen = len(stringIn)+1
ctrlString = "{:<"+str(consolePrinter.stringLen)+"}"
prevOverwriteLine = consolePrinter.overwriteLine
if prevOverwriteLine:
#Previous line entry can be overwritten, so do so
sys.stdout.write("\r" + ctrlString.format(stringIn))
else:
#Previous line entry cannot be overwritten, take a new line
sys.stdout.write("\n" + stringIn)
sys.stdout.flush()
#Update the class variable for prevOverwriteLine
consolePrinter.overwriteLine = overwriteThisLine
return
Which then is called via:
consolePrinter.writeline("text here", True)
If you want this line to be overwriteable
consolePrinter.writeline("text here",False)
if you don't.
Note, for it to work right, all messages pushed to the console would need to be through consolePrinter.writeline.
I generally recommend the f-string/format version, but sometimes you have a tuple, need, or want to use printf-style instead. I did this time and decided to use this:
>>> res = (1280, 720)
>>> '%04sx%04s' % res
'1280x 720'
Thought it was a touch more readable than the format version:
>>> f'{res[0]:>4}x{res[1]:>4}'
First check to see if the string's length needs to be shortened, then add spaces until it is as long as the field length.
fieldLength = 15
string1 = string1[0:15] # If it needs to be shortened, shorten it
while len(string1) < fieldLength:
rand += " "
Just whipped this up for my problem, it just adds a space until the length of string is more than the min_length you give it.
def format_string(str, min_length):
while len(str) < min_length:
str += " "
return str
I used beautifulsoup and I got a result form .get_text(). The result contains a long text:
alpha = ['\n\n\n\nIntroduction!!\nGood\xa0morning.\n\n\n\nHow\xa0are\xa0you?\n\n']
It can be noticed that the number of \n is not the same, and there are \xa0 for spacing.
I want to slice every group of \n (\n\n or \n\n\n or \n\n\n\n ) and replace \xa0 with a space in a new list, to look like this:
beta = ['Introduction!!','Good morning.','How are you?']
How can I do it?
Thank you in advance.
I wrote a little script that solves your problem:
alpha = ['\n\n\n\nIntroduction!!\nGood\xa0morning.\n\n\n\nHow\xa0are\xa0you?\n\n']
beta = []
for s in alpha:
# Turning the \xa0 into spaces
s = s.replace('\xa0',' ')
# Breaking the string by \n
s = s.split('\n')
# Explanation 1
s = list(filter(lambda s: s!= '',s))
# Explanation 2
beta = beta + s
print(beta)
Explanation 1
As there is some sequences of \n inside the alpha string, the split() will generate some empty strings. The filter() that I wrote removes them from the list.
Explanation 2
When the s string got split, it turns into a list of strings. Then, we need to concatenate the lists.
i am trying to get the numbers in individual form added to a list.
For example, if i input 3245, i want the list to say
["3","2","4","5"]
I have tried using a for in statement but got back numbers ranging from 0 - 3244 which was expected.
Any insight would be greatly appreciated, i am very new to python and am trying to teach myself code and re-write all my projects for school that was done in c to turn them into python. NOTE: i am using python 3, not 2.
Here is the rest of my code if it helps.
cc = []
card = int(input("Credit Card: "))
for n in range(card):
cc.append(n)
print(cc)
First of all, you should either accept the input number as string or convert it to string. That way, you can just parse through each character in the string and add them to the list. Currently you are getting the number 0-3244 because of you are looping for the amount of inputted number and adding the loop index to your list. Therefore, this should do what you want
cc = []
card = input("Credit Card: ") # or str(int(input("Credit Card: ")))
# if you want to restrict it to integer
for n in range(len(card)): # loop by number of characters
cc.append(card[n]) # append each character
print(cc)
a = 3245
b = list(str(a))
print(b)
The above code can convert an integer to a list of characters. First convert the integer to a string and then convert the string to a list form.
you can just convert the integer to string and iterate through every character of the string and during the iteration just append to cc.
cc = []
card = int(input("Credit Card: "))
for i in str(card):
cc.append(i)
print(cc)
I'm using python 3.x. I'm trying to get the (int) number at the end of a string with format
string_example_1 = l-45-98-567-567-12
string_example_2 = s-89-657
or in general, a single lowercase letter followed by a number of integers separated by '-'. What I need is to get the last number (12 and 657 in these cases). I have archived this with the function
def ending(the_string):
out = ''
while the_string[-1].isdigit():
out = the_string[-1] + out
the_string = the_string[:-1]
return out
but I'm sure there must be a more pythonic way to do this. In a previous instance I check manually that the string starts the way I like by doing something like
if st[0].isalpha() and st[1]=='-' and st[2].isdigit():
statement...
I would just split the string on -, take the last of the splits and convert it to an integer.
string_example_1 = "l-45-98-567-567-12"
string_example_2 = "s-89-657"
def last_number(s):
return int(s.split("-")[-1])
print(last_number(string_example_1))
# 12
print(last_number(string_example_2))
# 657
Without regular expressions, you could reverse the string, take elements from the string while they're still numbers, and then reverse the result. In Python:
from itertools import takewhile
def extract_final_digits(s):
return int(''.join(reversed(list(takewhile(lambda c: c.isdigit(), reversed(s))))))
But the simplest is to just split on a delimiter and take the final element in the split list.
Example like "3-5/description". I'd like extract the numbers next to the dash -, which are 3 and 5 in this example. The description next to the / is a str containing no number.
I want a tool to help me extract number from str like this like this func("3-5/description")returns [3,5]
You can do a regex match to capture the digits before and after the '-'
import re
def func(input):
return re.match(r'(\d+)[-](\d+)', x).groups()
func("3-5/description")