create a string of variable lenght
Tracubik
i want to print on linux console (terminal) a message like this one:
********************************
error message of variable lenght
********************************
to print the asterisks line i do this:
def StringOfAsterisks(myString):
asterisksString = "*"
for i in range(1,len(myString):
asterisksString += "*"
print asterisksString
so i create the asterisksString of the lenght i need
There is a better way of creating asterisksString?
the code seem to work for me, but it doesn't work properly if in errorMsg
there is some "esotic" char like euro char (€):
>>> euro = "€"
>>> len(euro)
3
how i can solve this?
Thank you all in advance and sorry for my bad english
Nico
Tim Chase
> ********************************
> error message of variable lenght
> ********************************
>
> to print the asterisks line i do this:
>
> def StringOfAsterisks(myString):
> asterisksString = "*"
> for i in range(1,len(myString):
> asterisksString += "*"
> print asterisksString
>
> so i create the asterisksString of the lenght i need
>
> There is a better way of creating asterisksString?
well, to make it more pythonic (ignoring camel-case
variable-names for now), I'd just use
print '*' * len(myString)
print myString
print '*' * len(myString)
possibly stashing the resulting asterisksString once:
asterisks_string = '*' * len(my_string)
print asterisks_string
print my_string
print asterisks_string
If I used it in multiple places, I might wrap it in a function
and/or define a "DIVIDER_CHARACTER" constant, something like
DIVIDER_CHARACTER = '*'
def surround(s, divider=DIVIDER_CHARACTER):
d = divider[0]
print d * len(s)
print s
print d * len(s)
surround('hello')
surround('world', '-')
surround('foo', 'xo')
depending on the sort of behavior you want
> the code seem to work for me, but it doesn't work properly if in errorMsg
> there is some "esotic" char like euro char (€):
>
>>>> euro = "€"
>>>> len(euro)
> 3
I suspect you're seeing the byte-representation of your string
with a particular-yet-undisclosed encoding. If it was a unicode
string (a good idea to specify the encoding at the top of your
file), the length should be accurate, so what happens if you
>>> euro = u"€"
>>> len(euro)
? (I don't have ready access to a terminal where I can enter
unicode characters, and you don't display the representation of
the string with
print repr(euro)
so I can steal the byte values to recreate it; but I suspect the
result will correctly be 1).
-tkc
Peter Otten
> Hi all,
>
> i want to print on linux console (terminal) a message like this one:
>
> ********************************
> error message of variable lenght
> ********************************
>
> to print the asterisks line i do this:
>
> def StringOfAsterisks(myString):
> asterisksString = "*"
> for i in range(1,len(myString):
> asterisksString += "*"
> print asterisksString
>
> so i create the asterisksString of the lenght i need
>
> There is a better way of creating asterisksString?
> >>> "*" * 10
'**********'
> the code seem to work for me, but it doesn't work properly if in errorMsg
> there is some "esotic" char like euro char (€):
>
>>>> euro = "€"
>>>> len(euro)
> 3
>
> how i can solve this?
This is less likely to fail when you use unicode strings:
>>> def print_message(s):
... print "*" * len(s)
... print s
... print "*" * len(s)
...
>>> print_message(u"You are leaving the € zone")
**************************
You are leaving the € zone
**************************
Peter
Günther Dietrich
>i want to print on linux console (terminal) a message like this one:
>
>********************************
>error message of variable lenght
>********************************
>
>to print the asterisks line i do this:
>
>def StringOfAsterisks(myString):
> asterisksString = "*"
> for i in range(1,len(myString):
> asterisksString += "*"
> print asterisksString
def StringOfAsterisks(myString):
print(''.ljust(len(myString), '*'))
You might use string methods .rjust() or .center() instead of method
.ljust().
>the code seem to work for me, but it doesn't work properly if in errorMsg
>there is some "esotic" char like euro char (€):
>
>>>> euro = "€"
>>>> len(euro)
>3
Maybe you might solve this if you decode your string to unicode.
Example:
|>>> euro = "€"
|>>> len(euro)
|3
|>>> u_euro = euro.decode('utf_8')
|>>> len(u_euro)
|1
Adapt the encoding ('utf_8' in my example) to whatever you use.
Or create the unicode string directly:
|>>> u_euro = u'€'
|>>> len(u_euro)
|1
Best regards,
Günther
Tracubik
scritto:
> Maybe you might solve this if you decode your string to unicode.
> Example:
>
> |>>> euro = "€"
> |>>> len(euro)
> |3
> |>>> u_euro = euro.decode('utf_8')
> |>>> len(u_euro)
> |1
>
> Adapt the encoding ('utf_8' in my example) to whatever you use.
>
> Or create the unicode string directly:
>
> |>>> u_euro = u'€'
> |>>> len(u_euro)
> |1
>
>
>
> Best regards,
>
> Günther
thank you, your two solution is really interesting.
is there a possible to set unicode encoding by default for my python
scripts?
i've tried inserting
# -*- coding: utf-8 -*-
at the beginning of my script but doesn't solve the problem
MRAB
That tells Python which encoding the file is using, but you still need
to save the file in that encoding.
Benjamin Kaplan
First of all, if you haven't read this before, please do. It will make
this much clearer.
http://www.joelonsoftware.com/articles/Unicode.html
To reiterate: UTF-8 IS NOT UNICODE!!!!
In Python 2, '*' signifies a byte string. It is read as a sequence of
bytes and interpreted as a sequence of bytes When Python encounters
the sequence 0x27 0xe2 0x82 0xac 0x27 in the code (the UTF-8 bytes for
'€') it interprets it as 3 bytes between the two quotes. It doesn't
care about characters or anything like that. u'*' signifies a Unicode
string. Python will attempt to convert the sequence of bytes into a
sequence of characters. It can use any encoding for that: cp1252,
utf-8, MacRoman, ISO-8859-15. UTF-8 isn't special, it's just one of
the few encodings capable of storing all of the possible Unicode
characters.
What the line at the top says is that the file should be read using
UTF-8. Byte strings are still just sequences of bytes- this doesn't
affect them. But any Unicode string will be decoded using UTF-8. IF
python looks at the above sequence of bytes as a Unicode string, it
views the 3 bytes as a single character. When you ask for it's length,
it returns the number of characters.
Solution to your problem: in addition to keeping the #-*- coding ...
line, go with Günther's advice and use Unicode strings.
> --
> http://mail.python.org/mailman/listinfo/python-list
>
Tracubik
> First of all, if you haven't read this before, please do. It will make
> this much clearer.
> http://www.joelonsoftware.com/articles/Unicode.html
i'm reading it right now, thanks :-)
[cut]
> Solution to your problem: in addition to keeping the #-*- coding ...
> line, go with Günther's advice and use Unicode strings.
that is: always use the "u" operator (i.e. my_name = u"Nico"), right?
Ciao,
Nico
Benjamin Kaplan
Short answer: yes.
Slightly longer explanation for future reference: This is true for
Python 2 but not Python 3. One of the big changes in Python 3 is that
strings are Unicode by default because you're not the only one who
runs into this problem. So in Python 3, just writing 'Nico' will make
a Unicode string and you have to explicitly declare b'Nico' if you
want to look at it as a series of bytes.