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Suppression des zéros de fin dans Python

J'ai besoin de trouver un moyen de convertir les chaînes suivantes en python:

0.000       => 0
0           => 0
123.45000   => 123.45
0000        => 0
123.4506780 => 123.450678

et ainsi de suite. J'ai essayé .rstrip ('0'). Rstrip ('.'), Mais cela ne fonctionne pas si l'entrée est 0 ou 00.

Des idées? Merci!

25
Raiders

Mis à jour Généralisé pour maintenir la précision et gérer les valeurs invisibles:

import decimal
import random

def format_number(num):
    try:
        dec = decimal.Decimal(num)
    except:
        return 'bad'
    tup = dec.as_Tuple()
    delta = len(tup.digits) + tup.exponent
    digits = ''.join(str(d) for d in tup.digits)
    if delta <= 0:
        zeros = abs(tup.exponent) - len(tup.digits)
        val = '0.' + ('0'*zeros) + digits
    else:
        val = digits[:delta] + ('0'*tup.exponent) + '.' + digits[delta:]
    val = val.rstrip('0')
    if val[-1] == '.':
        val = val[:-1]
    if tup.sign:
        return '-' + val
    return val

# test data
NUMS = '''
    0.0000      0
    0           0
    123.45000   123.45
    0000        0
    123.4506780 123.450678
    0.1         0.1
    0.001       0.001
    0.005000    0.005
    .1234       0.1234
    1.23e1      12.3
    -123.456    -123.456
    4.98e10     49800000000
    4.9815135   4.9815135
    4e30        4000000000000000000000000000000
    -0.0000000000004 -0.0000000000004
    -.4e-12     -0.0000000000004
    -0.11112    -0.11112
    1.3.4.5     bad
    -1.2.3      bad
'''

for num, exp in [s.split() for s in NUMS.split('\n') if s]:
    res = format_number(num)
    print res
    assert exp == res

Production:

0
0
123.45
0
123.450678
0.1
0.001
0.005
0.1234
12.3
-123.456
49800000000
4.9815135
4000000000000000000000000000000
-0.0000000000004
-0.0000000000004
-0.11112
bad
bad
22
samplebias

Vous pouvez utiliser format strings si vous le souhaitez, mais sachez que vous devrez peut-être définir la précision souhaitée, car les chaînes de format ont leur propre logique pour cela par défaut. Janneb suggère une précision de 17 dans ne autre réponse .

'{:g}'.format(float(your_string_goes_here))

Après y avoir réfléchi un peu plus, cependant, je pense que la solution la plus simple et la meilleure est simplement de lancer la chaîne deux fois (comme le jathanisme suggère ):

str(float(your_string_goes_here))

Edit: Ajout de clarification en raison du commentaire.

11
arussell84

Pour les nombres à virgule flottante, vous pouvez simplement transtyper la chaîne en float:

>>> float('123.4506780')
123.450678

Pour les valeurs nulles, vous pouvez simplement les convertir en un entier:

>>> int('0000')
0

Lors de l'impression, les valeurs numériques sont automatiquement converties en chaînes. Si vous en avez besoin pour être des chaînes, vous pouvez simplement les reconvertir en chaînes avec str(), par exemple:

>>> str(float('123.4506780'))
'123.450678'
8
jathanism
'%.17g' % float(mystr)

en fonction de ce que vous voulez vraiment faire ..

2
janneb

Scénario:

def tidy_float(s):
    """Return tidied float representation.
    Remove superflous leading/trailing zero digits.
    Remove '.' if value is an integer.
    Return '****' if float(s) fails.
    """
    # float?
    try:
        f = float(s)
    except ValueError:
        return '****'
    # int?
    try:
        i = int(s)
        return str(i)
    except ValueError:
        pass
    # scientific notation?
    if 'e' in s or 'E' in s:
        t = s.lstrip('0')
        if t.startswith('.'): t = '0' + t
        return t
    # float with integral value (includes zero)?
    i = int(f)
    if i == f:
        return str(i)
    assert '.' in s
    t = s.strip('0')
    if t.startswith('.'): t = '0' + t
    if t.endswith('.'): t += '0'
    return t

if __name__ == "__main__":

    # Each line has test string followed by expected output
    tests = """
    0.000 0
    0 0
    0000 0
    0.4000 0.4
    0.0081000 0.0081
    103.45 103.45
    103.4506700 103.45067
    14500.0012 14500.0012
    478000.89 478000.89
    993.59.18 ****
    12.5831.400 ****
    .458 0.458
    .48587000 0.48587
    .0000 0
    10000 10000
    10000.000 10000
    -10000 -10000
    -10000.000 -10000
    1.23e2 1.23e2
    1.23e10 1.23e10
    .123e10 0.123e10
     """.splitlines()

    for test in tests:
        x = test.split()
        if not x: continue
        data, expected = x
        actual = tidy_float(data)
        print "data=%r exp=%r act=%r %s" % (
            data, expected, actual, ["**FAIL**", ""][actual == expected])

Sortie (Python 2.7.1):

data='0.000' exp='0' act='0'
data='0' exp='0' act='0'
data='0000' exp='0' act='0'
data='0.4000' exp='0.4' act='0.4'
data='0.0081000' exp='0.0081' act='0.0081'
data='103.45' exp='103.45' act='103.45'
data='103.4506700' exp='103.45067' act='103.45067'
data='14500.0012' exp='14500.0012' act='14500.0012'
data='478000.89' exp='478000.89' act='478000.89'
data='993.59.18' exp='****' act='****'
data='12.5831.400' exp='****' act='****'
data='.458' exp='0.458' act='0.458'
data='.48587000' exp='0.48587' act='0.48587'
data='.0000' exp='0' act='0'
data='10000' exp='10000' act='10000'
data='10000.000' exp='10000' act='10000'
data='-10000' exp='-10000' act='-10000'
data='-10000.000' exp='-10000' act='-10000'
data='1.23e2' exp='1.23e2' act='1.23e2'
data='1.23e10' exp='1.23e10' act='1.23e10'
data='.123e10' exp='0.123e10' act='0.123e10'
1
John Machin

PREMIÈRE "SOLUTION"

import re
regx=re.compile('(?<![\d.])'
                '(?!\d*\.\d*\.)'  # excludes certain string as not being numbers
                '((\d|\.\d)([\d.])*?)'  # the only matching  group
                '([0\.]*)'
                '(?![\d.])')
regx.sub('\\1',ch)

.

EDIT 1

John Machin a dit que 10000 et 10000,000 produisent 1 au lieu de 10000

J'ai corrigé la fonction de remplacement à l'aide de (?!(?<=0)\.)

import re
regx = re.compile('(?<![\d.])'       '(?![1-9]\d*(?![\d.])|\d*\.\d*\.)'
                  '0*(?!(?<=0)\.)'
                  '([\d.]+?)'      # the only group , which is kept
                  '\.?0*'
                  '(?![\d.])')    
regx.sub('\\1',ch)               

.

EDIT 2

Pour corriger les lacunes restantes ['. 0000' produisant '.', signalé par John Machin, et '000078000' produisant '78'], j'ai réécrit un regex construit sur une nouvelle idée. C'est plus simple. Le regex détecte tous les types de nombres.

Cette solution supprime non seulement les zéros de fin, mais également les zéros de cap. Voici la comparaison de cette solution avec tidy_float() de John Machin, number_format() de samplebias, '{:g}'.format() de arussell84. Il y a quelques différences entre les résultats de ma fonction (tous corrects cette fois) et les autres:

import re
def number_shaver(ch,
                  regx = re.compile('(?<![\d.])0*(?:'
                                    '(\d+)\.?|\.(0)'
                                    '|(\.\d+?)|(\d+\.\d+?)'
                                    ')0*(?![\d.])')  ,
                  repl = lambda mat: mat.group(mat.lastindex)
                                     if mat.lastindex!=3
                                     else '0' + mat.group(3) ):
    return regx.sub(repl,ch)


def tidy_float(s):  # John Machin
    """Return tidied float representation.
    Remove superflous leading/trailing zero digits.
    Remove '.' if value is an integer.
    Return '****' if float(s) fails.
    """
    # float?
    try:
        f = float(s)
    except ValueError:
        return s
    # int?
    try:
        i = int(s)
        return str(i)
    except ValueError:
        pass
    # scientific notation?
    if 'e' in s or 'E' in s:
        t = s.lstrip('0')
        if t.startswith('.'): t = '0' + t
        return t
    # float with integral value (includes zero)?
    i = int(f)
    if i == f:
        return str(i)
    assert '.' in s
    t = s.strip('0')
    if t.startswith('.'): t = '0' + t
    if t.endswith('.'): t += '0'
    return t


def format_float(s):  # arrussell84
    return '{:g}'.format(float(s)) if s.count('.')<2 \
           else "Can't treat"


import decimal
def format_number(num):
    try:
        dec = decimal.Decimal(num)
    except:
        return 'bad'
    tup = dec.as_Tuple()
    delta = len(tup.digits) + tup.exponent
    digits = ''.join(str(d) for d in tup.digits)
    if delta <= 0:
        zeros = abs(tup.exponent) - len(tup.digits)
        val = '0.' + ('0'*zeros) + digits
    else:
        val = digits[:delta] + ('0'*tup.exponent) + '.' + digits[delta:]
    val = val.rstrip('0')
    if val[-1] == '.':
        val = val[:-1]
    if tup.sign:
        return '-' + val
    return val


numbers = ['23456000', '23456000.', '23456000.000',
           '00023456000', '000023456000.', '000023456000.000',
           '10000', '10000.', '10000.000',
           '00010000', '00010000.', '00010000.000',
           '24', '24.', '24.000',
           '00024', '00024.', '00024.000',
           '8', '8.', '8.000',
           '0008', '0008.', '0008.000',
           '0', '00000', '0.', '000.',
           '\n',
           '0.0', '0.000', '000.0', '000.000', '.000000', '.0',
           '\n',
           '.00023456', '.00023456000', '.00503', '.00503000',
           '.068', '.0680000', '.8', '.8000',
           '.123456123456', '.123456123456000',
           '.657', '.657000', '.45', '.4500000', '.7', '.70000',
           '\n',
           '0.0000023230000', '000.0000023230000',
           '0.0081000', '0000.0081000',
           '0.059000', '0000.059000',
           '0.78987400000', '00000.78987400000',
           '0.4400000', '00000.4400000',
           '0.5000', '0000.5000',
           '0.90', '000.90', '0.7', '000.7',
           '\n',
           '2.6', '00002.6', '00002.60000',
           '4.71', '0004.71', '0004.7100',
           '23.49', '00023.49', '00023.490000',
           '103.45', '0000103.45', '0000103.45000',
           '10003.45067', '000010003.45067', '000010003.4506700',
           '15000.0012', '000015000.0012', '000015000.0012000',
           '78000.89', '000078000.89', '000078000.89000',
           '\n',
           '.0457e10', '.0457000e10','00000.0457000e10',
           '258e8', '2580000e4', '0000000002580000e4',
           # notice the difference of exponents
           '0.782e10', '0000.782e10', '0000.7820000e10',
           '1.23E2', '0001.23E2', '0001.2300000E2',
           '432e-102', '0000432e-102', '004320000e-106',
           # notice the difference of exponents
           '1.46e10', '0001.46e10', '0001.4600000e10',
           '1.077e-300', '0001.077e-300', '0001.077000e-300',
           '1.069e10', '0001.069e10', '0001.069000e10',
           '105040.03e10', '000105040.03e10', '105040.0300e10',
           '\n',
           '..18000', '25..00',  '36...77', '2..8',
           '3.8..9', '.12500.', '12.51.400' ]

pat = '% 18s% -15s% -15s% -15s% s' li = [pat% ('nombre testé', 'float_shaver', 'tidy_float', "format_number ()", "'{: g}'. format () ")] li.extend (pat% (n, number_shaver (n), tidy_float (n), format_number (n), format_float (n)) if n! = '\ n' else '\ n' for n en chiffres)

imprimer '\ n'.join (li)

résultat de la comparaison:

     tested number  float_shaver    tidy_float      format_number() '{:g}'.format()
          23456000  23456000        23456000        23456000        2.3456e+07
         23456000.  23456000        23456000        23456000        2.3456e+07
      23456000.000  23456000        23456000        23456000        2.3456e+07
       00023456000  23456000        23456000        23456000        2.3456e+07
     000023456000.  23456000        23456000        23456000        2.3456e+07
  000023456000.000  23456000        23456000        23456000        2.3456e+07
             10000  10000           10000           10000           10000
            10000.  10000           10000           10000           10000
         10000.000  10000           10000           10000           10000
          00010000  10000           10000           10000           10000
         00010000.  10000           10000           10000           10000
      00010000.000  10000           10000           10000           10000
                24  24              24              24              24
               24.  24              24              24              24
            24.000  24              24              24              24
             00024  24              24              24              24
            00024.  24              24              24              24
         00024.000  24              24              24              24
                 8  8               8               8               8
                8.  8               8               8               8
             8.000  8               8               8               8
              0008  8               8               8               8
             0008.  8               8               8               8
          0008.000  8               8               8               8
                 0  0               0               0               0
             00000  0               0               0               0
                0.  0               0               0               0
              000.  0               0               0               0


               0.0  0               0               0               0
             0.000  0               0               0               0
             000.0  0               0               0               0
           000.000  0               0               0               0
           .000000  0               0               0               0
                .0  0               0               0               0


         .00023456  0.00023456      0.00023456      0.00023456      0.00023456
      .00023456000  0.00023456      0.00023456      0.00023456      0.00023456
            .00503  0.00503         0.00503         0.00503         0.00503
         .00503000  0.00503         0.00503         0.00503         0.00503
              .068  0.068           0.068           0.068           0.068
          .0680000  0.068           0.068           0.068           0.068
                .8  0.8             0.8             0.8             0.8
             .8000  0.8             0.8             0.8             0.8
     .123456123456  0.123456123456  0.123456123456  0.123456123456  0.123456
  .123456123456000  0.123456123456  0.123456123456  0.123456123456  0.123456
              .657  0.657           0.657           0.657           0.657
           .657000  0.657           0.657           0.657           0.657
               .45  0.45            0.45            0.45            0.45
          .4500000  0.45            0.45            0.45            0.45
                .7  0.7             0.7             0.7             0.7
            .70000  0.7             0.7             0.7             0.7


   0.0000023230000  0.000002323     0.000002323     0.000002323     2.323e-06
 000.0000023230000  0.000002323     0.000002323     0.000002323     2.323e-06
         0.0081000  0.0081          0.0081          0.0081          0.0081
      0000.0081000  0.0081          0.0081          0.0081          0.0081
          0.059000  0.059           0.059           0.059           0.059
       0000.059000  0.059           0.059           0.059           0.059
     0.78987400000  0.789874        0.789874        0.789874        0.789874
 00000.78987400000  0.789874        0.789874        0.789874        0.789874
         0.4400000  0.44            0.44            0.44            0.44
     00000.4400000  0.44            0.44            0.44            0.44
            0.5000  0.5             0.5             0.5             0.5
         0000.5000  0.5             0.5             0.5             0.5
              0.90  0.9             0.9             0.9             0.9
            000.90  0.9             0.9             0.9             0.9
               0.7  0.7             0.7             0.7             0.7
             000.7  0.7             0.7             0.7             0.7


               2.6  2.6             2.6             2.6             2.6
           00002.6  2.6             2.6             2.6             2.6
       00002.60000  2.6             2.6             2.6             2.6
              4.71  4.71            4.71            4.71            4.71
           0004.71  4.71            4.71            4.71            4.71
         0004.7100  4.71            4.71            4.71            4.71
             23.49  23.49           23.49           23.49           23.49
          00023.49  23.49           23.49           23.49           23.49
      00023.490000  23.49           23.49           23.49           23.49
            103.45  103.45          103.45          103.45          103.45
        0000103.45  103.45          103.45          103.45          103.45
     0000103.45000  103.45          103.45          103.45          103.45
       10003.45067  10003.45067     10003.45067     10003.45067     10003.5
   000010003.45067  10003.45067     10003.45067     10003.45067     10003.5
 000010003.4506700  10003.45067     10003.45067     10003.45067     10003.5
        15000.0012  15000.0012      15000.0012      15000.0012      15000
    000015000.0012  15000.0012      15000.0012      15000.0012      15000
 000015000.0012000  15000.0012      15000.0012      15000.0012      15000
          78000.89  78000.89        78000.89        78000.89        78000.9
      000078000.89  78000.89        78000.89        78000.89        78000.9
   000078000.89000  78000.89        78000.89        78000.89        78000.9


          .0457e10  0.0457e10       0.0457e10       457000000       4.57e+08
       .0457000e10  0.0457e10       0.0457000e10    457000000       4.57e+08
  00000.0457000e10  0.0457e10       0.0457000e10    457000000       4.57e+08
             258e8  258e8           258e8           25800000000     2.58e+10
         2580000e4  2580000e4       2580000e4       25800000000     2.58e+10
0000000002580000e4  2580000e4       2580000e4       25800000000     2.58e+10
          0.782e10  0.782e10        0.782e10        7820000000      7.82e+09
       0000.782e10  0.782e10        0.782e10        7820000000      7.82e+09
   0000.7820000e10  0.782e10        0.7820000e10    7820000000      7.82e+09
            1.23E2  1.23E2          1.23E2          123             123
         0001.23E2  1.23E2          1.23E2          123             123
    0001.2300000E2  1.23E2          1.2300000E2     123             123
          432e-102  432e-102        432e-102        0.000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000432 4.32e-100
      0000432e-102  432e-102        432e-102        0.000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000432 4.32e-100
    004320000e-106  4320000e-106    4320000e-106    0.000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000432 4.32e-100
           1.46e10  1.46e10         1.46e10         14600000000     1.46e+10
        0001.46e10  1.46e10         1.46e10         14600000000     1.46e+10
   0001.4600000e10  1.46e10         1.4600000e10    14600000000     1.46e+10
        1.077e-300  1.077e-300      1.077e-300      0.000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000001077 1.077e-300
     0001.077e-300  1.077e-300      1.077e-300      0.000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000001077 1.077e-300
  0001.077000e-300  1.077e-300      1.077000e-300   0.000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000001077 1.077e-300
          1.069e10  1.069e10        1.069e10        10690000000     1.069e+10
       0001.069e10  1.069e10        1.069e10        10690000000     1.069e+10
    0001.069000e10  1.069e10        1.069000e10     10690000000     1.069e+10
      105040.03e10  105040.03e10    105040.03e10    1050400300000000 1.0504e+15
   000105040.03e10  105040.03e10    105040.03e10    1050400300000000 1.0504e+15
    105040.0300e10  105040.03e10    105040.0300e10  1050400300000000 1.0504e+15


           ..18000  ..18000         ..18000         bad             Can't treat
            25..00  25..00          25..00          bad             Can't treat
           36...77  36...77         36...77         bad             Can't treat
              2..8  2..8            2..8            bad             Can't treat
            3.8..9  3.8..9          3.8..9          bad             Can't treat
           .12500.  .12500.         .12500.         bad             Can't treat
         12.51.400  12.51.400       12.51.400       bad             Can't treat

.

Je considère que ma solution présente deux avantages:

  • l'expression rationnelle et la fonction number_shave () sont courtes

  • number_shave () ne traite pas seulement un nombre à la fois mais détecte et traite également tous les nombres d'une chaîne. Voici un traitement que les solutions de John Machin et d'arrussel84 ne peuvent pas faire:

code:

numbers = [['', '23456000', '23456000.', '23456000.000 \n',
            '00023456000', '000023456000.', '000023456000.000 \n',
            '10000', '10000.', '10000.000 \n',
            '00010000', '00010000.', '00010000.000 \n',
            '24', '24.', '24.000 \n',
            '00024', '00024.', '00024.000 \n',
            '8', '8.', '8.000 \n',
            '0008', '0008.', '0008.000 \n',
            '0', '00000', '0.', '000.' ],




            ['0.0', '0.000', '000.0', '000.000', '.000000', '.0'],

            ['.00023456', '.00023456000', '.00503', '.00503000 \n',
             '.068', '.0680000', '.8', '.8000 \n',
             '.123456123456', '.123456123456000 \n',
             '.657', '.657000', '.45', '.4500000', '.7', '.70000'],

            ['0.0000023230000', '000.0000023230000 \n',
             '0.0081000', '0000.0081000 \n',
             '0.059000', '0000.059000 \n',
             '0.78987400000', '00000.78987400000 \n',
             '0.4400000', '00000.4400000 \n',
             '0.5000', '0000.5000 \n',
             '0.90', '000.90', '0.7', '000.7 '],

            ['2.6', '00002.6', '00002.60000 \n',
             '4.71', '0004.71', '0004.7100 \n',
             '23.49', '00023.49', '00023.490000 \n',
             '103.45', '0000103.45', '0000103.45000 \n',
             '10003.45067', '000010003.45067', '000010003.4506700 \n',
             '15000.0012', '000015000.0012', '000015000.0012000 \n',
             '78000.89', '000078000.89', '000078000.89000'],

            ['.0457e10', '.0457000e10 \n',
             '0.782e10', '0000.782e10', '0000.7820000e10 \n',
             '1.23E2', '0001.23E2', '0001.2300000E2 \n',
             '1.46e10', '0001.46e10', '0001.4600000e10 \n',
             '1.077e-456', '0001.077e-456', '0001.077000e-456 \n',
             '1.069e10', '0001.069e10', '0001.069000e10 \n',
             '105040.03e10', '000105040.03e10', '105040.03e10'],

            ['..18000', '25..00',  '36...77', '2..8 \n',
             '3.8..9', '.12500.', '12.51.400' ]]


import re
def number_shaver(ch,
                 regx = re.compile('(?<![\d.])0*(?:'
                                   '(\d+)\.?|\.(0)'
                                   '|(\.\d+?)|(\d+\.\d+?)'
                                   ')0*(?![\d.])')  ,
                 repl = lambda mat: mat.group(mat.lastindex)
                                    if mat.lastindex!=3
                                    else '0' + mat.group(3) ):
    return regx.sub(repl,ch)




for li in numbers:
    one_string = ' --- '.join(li)
    print one_string + '\n\n' + number_shaver(one_string) + \
          '\n\n' + 3*'---------------------' + '\n'

résultats des traitements de cordes contenant plusieurs nombres:

 --- 23456000 --- 23456000. --- 23456000.000 
 --- 00023456000 --- 000023456000. --- 000023456000.000 
 --- 10000 --- 10000. --- 10000.000 
 --- 00010000 --- 00010000. --- 00010000.000 
 --- 24 --- 24. --- 24.000 
 --- 00024 --- 00024. --- 00024.000 
 --- 8 --- 8. --- 8.000 
 --- 0008 --- 0008. --- 0008.000 
 --- 0 --- 00000 --- 0. --- 000.

 --- 23456000 --- 23456000 --- 23456000 
 --- 23456000 --- 23456000 --- 23456000 
 --- 10000 --- 10000 --- 10000 
 --- 10000 --- 10000 --- 10000 
 --- 24 --- 24 --- 24 
 --- 24 --- 24 --- 24 
 --- 8 --- 8 --- 8 
 --- 8 --- 8 --- 8 
 --- 0 --- 0 --- 0 --- 0

---------------------------------------------------------------

0.0 --- 0.000 --- 000.0 --- 000.000 --- .000000 --- .0

0 --- 0 --- 0 --- 0 --- 0 --- 0

---------------------------------------------------------------

.00023456 --- .00023456000 --- .00503 --- .00503000 
 --- .068 --- .0680000 --- .8 --- .8000 
 --- .123456123456 --- .123456123456000 
 --- .657 --- .657000 --- .45 --- .4500000 --- .7 --- .70000

0.00023456 --- 0.00023456 --- 0.00503 --- 0.00503 
 --- 0.068 --- 0.068 --- 0.8 --- 0.8 
 --- 0.123456123456 --- 0.123456123456 
 --- 0.657 --- 0.657 --- 0.45 --- 0.45 --- 0.7 --- 0.7

---------------------------------------------------------------

0.0000023230000 --- 000.0000023230000 
 --- 0.0081000 --- 0000.0081000 
 --- 0.059000 --- 0000.059000 
 --- 0.78987400000 --- 00000.78987400000 
 --- 0.4400000 --- 00000.4400000 
 --- 0.5000 --- 0000.5000 
 --- 0.90 --- 000.90 --- 0.7 --- 000.7 

0.000002323 --- 0.000002323 
 --- 0.0081 --- 0.0081 
 --- 0.059 --- 0.059 
 --- 0.789874 --- 0.789874 
 --- 0.44 --- 0.44 
 --- 0.5 --- 0.5 
 --- 0.9 --- 0.9 --- 0.7 --- 0.7 

---------------------------------------------------------------

2.6 --- 00002.6 --- 00002.60000 
 --- 4.71 --- 0004.71 --- 0004.7100 
 --- 23.49 --- 00023.49 --- 00023.490000 
 --- 103.45 --- 0000103.45 --- 0000103.45000 
 --- 10003.45067 --- 000010003.45067 --- 000010003.4506700 
 --- 15000.0012 --- 000015000.0012 --- 000015000.0012000 
 --- 78000.89 --- 000078000.89 --- 000078000.89000

2.6 --- 2.6 --- 2.6 
 --- 4.71 --- 4.71 --- 4.71 
 --- 23.49 --- 23.49 --- 23.49 
 --- 103.45 --- 103.45 --- 103.45 
 --- 10003.45067 --- 10003.45067 --- 10003.45067 
 --- 15000.0012 --- 15000.0012 --- 15000.0012 
 --- 78000.89 --- 78000.89 --- 78000.89

---------------------------------------------------------------

.0457e10 --- .0457000e10 
 --- 0.782e10 --- 0000.782e10 --- 0000.7820000e10 
 --- 1.23E2 --- 0001.23E2 --- 0001.2300000E2 
 --- 1.46e10 --- 0001.46e10 --- 0001.4600000e10 
 --- 1.077e-456 --- 0001.077e-456 --- 0001.077000e-456 
 --- 1.069e10 --- 0001.069e10 --- 0001.069000e10 
 --- 105040.03e10 --- 000105040.03e10 --- 105040.03e10

0.0457e10 --- 0.0457e10 
 --- 0.782e10 --- 0.782e10 --- 0.782e10 
 --- 1.23E2 --- 1.23E2 --- 1.23E2 
 --- 1.46e10 --- 1.46e10 --- 1.46e10 
 --- 1.077e-456 --- 1.077e-456 --- 1.077e-456 
 --- 1.069e10 --- 1.069e10 --- 1.069e10 
 --- 105040.03e10 --- 105040.03e10 --- 105040.03e10

---------------------------------------------------------------

..18000 --- 25..00 --- 36...77 --- 2..8 
 --- 3.8..9 --- .12500. --- 12.51.400

..18000 --- 25..00 --- 36...77 --- 2..8 
 --- 3.8..9 --- .12500. --- 12.51.400

---------------------------------------------------------------

.

Par conséquent, l'expression régulière peut également être utilisée pour simplement trouver tous les nombres dans une chaîne, sans supprimer les zéros si ce n'est pas souhaité.

.

PS: voir plus dans mon autre réponse qui explique le regex et son fonctionnement

1
eyquem

AJOUT À LA MODIFICATION 2 de mon autre réponse

(Tout était trop long pour être dans un seul poste)

Le modèle de l'expression régulière définit 4 sous-modèles, chacun correspondant à un certain type de nombres. Chaque fois que l'expression régulière correspond à une partie d'une chaîne, il n'y a qu'un seul des sous-modèles qui correspond, d'où la possibilité d'utiliser mat.lastindex dans la fonction de remplacement. Le code suivant montre les correspondances du sous-modèle avec différents nombres:

import re
def float_show(ch,
               regx = re.compile(
                   '(?<![\d.])'
                   '0*' # potentiel heading zeros
                   '(?:'
                   '(\d+)\.?' # INTEGERS :
                              # ~ pure integers non-0 or 0
                              #   000450 , 136000 , 87 , 000 , 0
                              # ~ integer part non-0 + '.'
                              #   0044. , 4100.
                              # ~ integer part 0 + '.'
                              #   000. , 0. 
                              # ~ integer part non-0 + '.' + fractional part 0:
                              #   000570.00 , 193.0 , 3.000

                   '|\.(0)' # SPECIAL CASE, 0 WITH FRACTIONAL PART :
                            # ~ integer part 0 + compulsory fractional part 0:
                            #   000.0, 0.000 , .0 , .00000

                   '|(\.\d+?)' # FLOATING POINT NUMBER
                               # ~ with integer part 0:
                               #   000.0890 , 0.52 , 0.1 , .077000 , .1400 , .0006010

                   '|(\d+\.\d+?)' # FLOATING POINT NUMBER
                                  # ~ with integer part non-0:
                                  #   0024000.013000 , 145.0235 , 3.00058
                   ')'
                   '0*' # potential tailing zeros
                   '(?![\d.])'),
               repl = lambda mat: mat.group(mat.lastindex)
                                  if mat.lastindex!=3
                                  else '0' + mat.group(3)  ):
    mat = regx.search(ch)
    if mat:
        return (ch,regx.sub(repl,ch),repr(mat.groups()))
    else:
        return (ch,'No match','No groups')


numbers = ['23456000', '23456000.', '23456000.000',
           '00023456000', '000023456000.', '000023456000.000',
           '10000', '10000.', '10000.000',
           '00010000', '00010000.', '00010000.000',
           '24', '24.', '24.000',
           '00024', '00024.', '00024.000',
           '8', '8.', '8.000',
           '0008', '0008.', '0008.000',
           '0', '00000', '0.', '000.',
           '\n',
           '0.0', '0.000', '000.0', '000.000', '.000000', '.0',
           '\n',
           '.00023456', '.00023456000', '.00503', '.00503000',
           '.068', '.0680000', '.8', '.8000',
           '.123456123456', '.123456123456000',
           '.657', '.657000', '.45', '.4500000', '.7', '.70000',
           '\n',
           '0.0000023230000', '000.0000023230000',
           '0.0081000', '0000.0081000',
           '0.059000', '0000.059000',
           '0.78987400000', '00000.78987400000',
           '0.4400000', '00000.4400000',
           '0.5000', '0000.5000',
           '0.90', '000.90', '0.7', '000.7',
           '\n',
           '2.6', '00002.6', '00002.60000',
           '4.71', '0004.71', '0004.7100',
           '23.49', '00023.49', '00023.490000',
           '103.45', '0000103.45', '0000103.45000',
           '10003.45067', '000010003.45067', '000010003.4506700',
           '15000.0012', '000015000.0012', '000015000.0012000',
           '78000.89', '000078000.89', '000078000.89000',
           '\n',
           '.0457e10', '.0457000e10',
           '0.782e10', '0000.782e10', '0000.7820000e10',
           '1.23E2', '0001.23E2', '0001.2300000E2',
           '1.46e10', '0001.46e10', '0001.4600000e10',
           '1.077e-456', '0001.077e-456', '0001.077000e-456',
           '1.069e10', '0001.069e10', '0001.069000e10',
           '105040.03e10', '000105040.03e10', '105040.0300e10',
           '\n',
           '..18000', '25..00',  '36...77', '2..8',
           '3.8..9', '.12500.', '12.51.400' ]

pat = '%20s  %-16s %s'
li = [pat % ('tested number ',' shaved float',' regx.search(number).groups()')]
li.extend(pat % float_show(ch) if ch!='\n' else '\n' for ch in numbers)
print '\n'.join(li)

démontre

      tested number    shaved float     regx.search(number).groups()
            23456000  23456000         ('23456000', None, None, None)
           23456000.  23456000         ('23456000', None, None, None)
        23456000.000  23456000         ('23456000', None, None, None)
         00023456000  23456000         ('23456000', None, None, None)
       000023456000.  23456000         ('23456000', None, None, None)
    000023456000.000  23456000         ('23456000', None, None, None)
               10000  10000            ('10000', None, None, None)
              10000.  10000            ('10000', None, None, None)
           10000.000  10000            ('10000', None, None, None)
            00010000  10000            ('10000', None, None, None)
           00010000.  10000            ('10000', None, None, None)
        00010000.000  10000            ('10000', None, None, None)
                  24  24               ('24', None, None, None)
                 24.  24               ('24', None, None, None)
              24.000  24               ('24', None, None, None)
               00024  24               ('24', None, None, None)
              00024.  24               ('24', None, None, None)
           00024.000  24               ('24', None, None, None)
                   8  8                ('8', None, None, None)
                  8.  8                ('8', None, None, None)
               8.000  8                ('8', None, None, None)
                0008  8                ('8', None, None, None)
               0008.  8                ('8', None, None, None)
            0008.000  8                ('8', None, None, None)
                   0  0                ('0', None, None, None)
               00000  0                ('0', None, None, None)
                  0.  0                ('0', None, None, None)
                000.  0                ('0', None, None, None)


                 0.0  0                (None, '0', None, None)
               0.000  0                (None, '0', None, None)
               000.0  0                (None, '0', None, None)
             000.000  0                (None, '0', None, None)
             .000000  0                (None, '0', None, None)
                  .0  0                (None, '0', None, None)


           .00023456  0.00023456       (None, None, '.00023456', None)
        .00023456000  0.00023456       (None, None, '.00023456', None)
              .00503  0.00503          (None, None, '.00503', None)
           .00503000  0.00503          (None, None, '.00503', None)
                .068  0.068            (None, None, '.068', None)
            .0680000  0.068            (None, None, '.068', None)
                  .8  0.8              (None, None, '.8', None)
               .8000  0.8              (None, None, '.8', None)
       .123456123456  0.123456123456   (None, None, '.123456123456', None)
    .123456123456000  0.123456123456   (None, None, '.123456123456', None)
                .657  0.657            (None, None, '.657', None)
             .657000  0.657            (None, None, '.657', None)
                 .45  0.45             (None, None, '.45', None)
            .4500000  0.45             (None, None, '.45', None)
                  .7  0.7              (None, None, '.7', None)
              .70000  0.7              (None, None, '.7', None)


     0.0000023230000  0.000002323      (None, None, '.000002323', None)
   000.0000023230000  0.000002323      (None, None, '.000002323', None)
           0.0081000  0.0081           (None, None, '.0081', None)
        0000.0081000  0.0081           (None, None, '.0081', None)
            0.059000  0.059            (None, None, '.059', None)
         0000.059000  0.059            (None, None, '.059', None)
       0.78987400000  0.789874         (None, None, '.789874', None)
   00000.78987400000  0.789874         (None, None, '.789874', None)
           0.4400000  0.44             (None, None, '.44', None)
       00000.4400000  0.44             (None, None, '.44', None)
              0.5000  0.5              (None, None, '.5', None)
           0000.5000  0.5              (None, None, '.5', None)
                0.90  0.9              (None, None, '.9', None)
              000.90  0.9              (None, None, '.9', None)
                 0.7  0.7              (None, None, '.7', None)
               000.7  0.7              (None, None, '.7', None)


                 2.6  2.6              (None, None, None, '2.6')
             00002.6  2.6              (None, None, None, '2.6')
         00002.60000  2.6              (None, None, None, '2.6')
                4.71  4.71             (None, None, None, '4.71')
             0004.71  4.71             (None, None, None, '4.71')
           0004.7100  4.71             (None, None, None, '4.71')
               23.49  23.49            (None, None, None, '23.49')
            00023.49  23.49            (None, None, None, '23.49')
        00023.490000  23.49            (None, None, None, '23.49')
              103.45  103.45           (None, None, None, '103.45')
          0000103.45  103.45           (None, None, None, '103.45')
       0000103.45000  103.45           (None, None, None, '103.45')
         10003.45067  10003.45067      (None, None, None, '10003.45067')
     000010003.45067  10003.45067      (None, None, None, '10003.45067')
   000010003.4506700  10003.45067      (None, None, None, '10003.45067')
          15000.0012  15000.0012       (None, None, None, '15000.0012')
      000015000.0012  15000.0012       (None, None, None, '15000.0012')
   000015000.0012000  15000.0012       (None, None, None, '15000.0012')
            78000.89  78000.89         (None, None, None, '78000.89')
        000078000.89  78000.89         (None, None, None, '78000.89')
     000078000.89000  78000.89         (None, None, None, '78000.89')


            .0457e10  0.0457e10        (None, None, '.0457', None)
         .0457000e10  0.0457e10        (None, None, '.0457', None)
            0.782e10  0.782e10         (None, None, '.782', None)
         0000.782e10  0.782e10         (None, None, '.782', None)
     0000.7820000e10  0.782e10         (None, None, '.782', None)
              1.23E2  1.23E2           (None, None, None, '1.23')
           0001.23E2  1.23E2           (None, None, None, '1.23')
      0001.2300000E2  1.23E2           (None, None, None, '1.23')
             1.46e10  1.46e10          (None, None, None, '1.46')
          0001.46e10  1.46e10          (None, None, None, '1.46')
     0001.4600000e10  1.46e10          (None, None, None, '1.46')
          1.077e-456  1.077e-456       (None, None, None, '1.077')
       0001.077e-456  1.077e-456       (None, None, None, '1.077')
    0001.077000e-456  1.077e-456       (None, None, None, '1.077')
            1.069e10  1.069e10         (None, None, None, '1.069')
         0001.069e10  1.069e10         (None, None, None, '1.069')
      0001.069000e10  1.069e10         (None, None, None, '1.069')
        105040.03e10  105040.03e10     (None, None, None, '105040.03')
     000105040.03e10  105040.03e10     (None, None, None, '105040.03')
      105040.0300e10  105040.03e10     (None, None, None, '105040.03')


             ..18000  No match         No groups
              25..00  No match         No groups
             36...77  No match         No groups
                2..8  No match         No groups
              3.8..9  No match         No groups
             .12500.  No match         No groups
           12.51.400  No match         No groups
1
eyquem