how to improve this simple block of code

[py]

Say I have...
x = "132.00"

but I'd like to display it to be "132" ...dropping the trailing
zeros...I currently try this

if x.endswith("0"):
x = x[:len(x)-1]
if x.endswith("0"):
x = x[:len(x)-1]
if x.endswith("."):
x = x[:len(x)-1]

I do it like this because if
x = "132.15" ...i dont want to modify it. But if
x = "132.60" ...I want it to become "132.6"

is there a better way to do this? It seems a bit ugly to me.

T.I.A
(thanks in advance)

 

[Juho Schultz]

Say I have...
x = "132.00"

but I'd like to display it to be "132" ...dropping the trailing
zeros...I currently try this

if x.endswith("0"):
x = x[:len(x)-1]
if x.endswith("0"):
x = x[:len(x)-1]
if x.endswith("."):
x = x[:len(x)-1]

I do it like this because if
x = "132.15" ...i dont want to modify it. But if
x = "132.60" ...I want it to become "132.6"

is there a better way to do this? It seems a bit ugly to me.

T.I.A
(thanks in advance)

x = x.rstrip('0') # removes trailing zeros
x = x.rstrip('.') # removes trailing dot(s)

 

[hanz]

Or combined:

x = x.rstrip('0.') # removes trailing zeroes and dots

 

[py]

x = x.rstrip('0.') # removes trailing zeroes and dots

knew there had to be a way, thanks.

 

[Peter Otten]

Or combined:

x = x.rstrip('0.') # removes trailing zeroes and dots

'13'

Oops.

Peter

 

[Roy Smith]

Say I have...
x = "132.00"

but I'd like to display it to be "132" ...dropping the trailing
zeros...I currently try this

This sounds to me like a job for regular expressions. Something like:

re.sub (r'\.?0*$', '', x)

will do what you want. Check out the re module in the docs for more
details.

 

[Matt Hammond]

Say I have...
x = "132.00"

but I'd like to display it to be "132" ...dropping the trailing
zeros...

How about:

if "." in x:
x, frac = x.split(".")
frac = frac.rstrip("0")
if frac:
x = x + "." + frac


Copes if x = "132" too. If there'll always be a decimal point, then you
can leave off the initial "if".



Matt
--

| Matt Hammond
| R&D Engineer, BBC Research & Development, Tadworth, Surrey, UK.
| http://kamaelia.sf.net/
| http://www.bbc.co.uk/rd/

 

[Mike Meyer]

Say I have...
x = "132.00"
but I'd like to display it to be "132" ...dropping the trailing
zeros...I currently try this

The two-strip solution is cleaner, but:

if x.endswith("0"):
x = x[:len(x)-1]

x = x[:-1]
or
del x[-1]

both improve that one statement.

<mike

 

[Peter Otten]

Say I have...
x = "132.00"
but I'd like to display it to be "132" ...dropping the trailing
zeros...I currently try this

The two-strip solution is cleaner, but:

if x.endswith("0"):
x = x[:len(x)-1]

x = x[:-1]
or
del x[-1]

both improve that one statement.

del "it's tempting not to try"[-1]

Traceback (most recent call last):
File "<stdin>", line 1, in ?
TypeError: object doesn't support item deletion

Just-pointing-out-what-does-not-work-ly yours

Peter

 

[Gary Duzan]

x = "132.15" ...i dont want to modify it. But if
x = "132.60" ...I want it to become "132.6"

is there a better way to do this? It seems a bit ugly to me.

The following works as long as you don't mind losing leading zeros
as well:

x = x.strip('0')

Gary Duzan
Motorola CHS

 

[Matt Hammond]

How about:

if "." in x:
x, frac = x.split(".")
frac = frac.rstrip("0")
if frac:
x = x + "." + frac

Or simpler still:

if "." in x:
x = x.rstrip("0")
x = x.rstrip(".")


More concise, but slightly less readable IMO:

if "." in x:
x = x.rstrip("0").rstrip(".")

--

| Matt Hammond
| R&D Engineer, BBC Research & Development, Tadworth, Surrey, UK.
| http://kamaelia.sf.net/
| http://www.bbc.co.uk/rd/

 

[Peter Hansen]

knew there had to be a way, thanks.

But that's not it.

This is a wonderful opportunity for you to learn about unit testing, and
begin the long process of developing good testing habits. Of all the
ideas posted, I believe only Mark Hammond's would correctly pass the
basic obvious test cases, and I don't think anyone (without actually
having checked with tests) should be saying even his is clearly correct.

import unittest
from yourmodule import stripZeros # or whatever you have

class Tests(unittest.TestCase):
def test01(self):
'check zero-stripper'
for input, expected in [
('', ''),
('0', '0'),
('0.0', '0'),
('0.', '0'),
('000.', '000'),
('10', '10'),
('10.0', '10'),
('foo', 'foo'),
('foo.', 'foo'), # ??
('132.15', '132.15'),
('132.60', '132.6'),
('132.00', '132'),
('132.00000', '132'),
('132.000001', '132.000001'),
# add others to taste
]:
self.assertEquals(expected, stripZeros(input))

unittest.main()


Change the above test cases to match what you really want if they're not
correct, then run the script and make sure everything passes.

-Peter

 

[Peter Otten]

Of all the ideas posted, I believe only Mark Hammond's would correctly
pass the basic obvious test cases

Too bad he didn't post at all

Peter

 

[Peter Hansen]

Too bad he didn't post at all

D'oh! There was a typo in my message above. Naturally, I meant to
write "M. Hammond" instead of "Mark Hammond". ;-)

Sorry Matt!

-Peter

 

[Mel Wilson]

Say I have...
x = "132.00"

but I'd like to display it to be "132" ...dropping the trailing
zeros...

print '%g' % (float(x),)

might work.

Mel.

 

[Xavier Morel]

print '%g' % (float(x),)

might work.

Mel.

The input is a string, %g expects a float, TypeError exception.

 

[Xavier Morel]

Forget about the previous mail, i just saw you were converting the
string to float beforehand, in which case he would more than likely run
into the good ol' float imprecision issue sooner than later.

Not to mention that %g formats to scientific notation (e.g. exponential
format with the exponent always being a multiple of 3), he'd probably
use "%f".

 

[Steven D'Aprano]

Say I have...
x = "132.00"

but I'd like to display it to be "132" ...dropping the trailing
zeros...I currently try this

Mucking about with the string is one solution. Here is another:

print int(float(x))

I do it like this because if
x = "132.15" ...i dont want to modify it. But if
x = "132.60" ...I want it to become "132.6"

Then you want:

x = float("123.60") # full precision floating point value
r = round(x, 1) # rounded to one decimal place