zeros - string module python
Eliminando ceros finales en Python (7)
ADICION AL EDIT 2 de mi otra respuesta.
(Todo fue demasiado largo para estar en un solo post)
El patrón de la expresión regular define 4 sub-patrones, cada uno de los cuales coincide con un cierto tipo de números. Cada vez que la expresión regular coincide con una parte de una cadena, solo hay uno de los sub-patrones que coinciden, de ahí la posibilidad de usar mat.lastindex en la función de reemplazo. El siguiente código muestra los emparejamientos del sub-patrón con varios números:
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)
demuestra
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
Esta pregunta ya tiene una respuesta aquí:
- Formato de flotadores en Python sin ceros superfluos 14 respuestas
Necesito encontrar una manera de convertir las siguientes cadenas en python:
0.000 => 0
0 => 0
123.45000 => 123.45
0000 => 0
123.4506780 => 123.450678
Etcétera. Intenté .rstrip (''0''). Rstrip (''.''), Pero eso no funciona si la entrada es 0 o 00.
¿Algunas ideas? ¡Gracias!
PRIMERA "SOLUCION"
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)
.
EDITAR 1
John Machin dijo que 10000 y 10000,000 producen 1 en lugar de 10000.
Corrigí la función de reemplazo con la ayuda 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)
.
Editar 2
Para corregir las deficiencias restantes [ ''.0000'' producir ''.'' , señalado por John Machin, y ''000078000'' produciendo ''78'' ], reescribí una construcción de expresiones regulares sobre una nueva idea. Es mas sencillo La expresión regular detecta todos los tipos de números.
Esta solución no solo corta los ceros finales, sino también los ceros de rumbo. Aquí está la comparación de esta solución con tidy_float() John Machin, number_format() samplebias, ''{:g}''.format() arussell84. Hay algunas diferencias entre los resultados de mi función (todas correctas esta vez) y las otras:
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% (''número probado'', ''float_shaver'', ''tidy_float'', "format_number ()", "''{: g}''. format () ")] li.extend (pat% (n, number_shaver (n), tidy_float (n), format_number (n), format_float (n)) si n! = ''/ n'' else ''/ n'' para n en números)
imprimir ''/ n''.join (li)
Resultado de la comparación:
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
.
Considero que mi solución tiene dos ventajas:
La expresión regular y la función number_shave () son cortas
number_shave () no solo trata un número a la vez sino que también detecta y trata todos los números en una cadena. Aquí hay un tratamiento que las soluciones de John Machin y arrussel84 no pueden hacer:
código:
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''
Resultados de los tratamientos de cuerdas que contienen varios números:
--- 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
---------------------------------------------------------------
.
En consecuencia, la expresión regular también se puede utilizar para encontrar simplemente todos los números en una cadena, sin eliminar los ceros si no se desea.
.
PD: vea más en mi otra respuesta que explica la expresión regular y su funcionamiento
Guión:
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])
Salida (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''
Para los números de punto flotante, simplemente puede convertir la cadena a un float :
>>> float(''123.4506780'')
123.450678
Para los valores de cero, puede simplemente convertirlos a un entero:
>>> int(''0000'')
0
Cuando se imprimen, los valores numéricos se convierten automáticamente en cadenas. Si necesita que estas sean realmente cadenas, puede simplemente volver a formar cadenas con str() , por ejemplo:
>>> str(float(''123.4506780''))
''123.450678''
Puede usar cadenas de formato si lo desea, pero tenga en cuenta que es posible que necesite configurar la precisión deseada, ya que las cadenas de formato tienen su propia lógica para esto de manera predeterminada. Janneb sugiere una precisión de 17 en otra respuesta .
''{:g}''.format(float(your_string_goes_here))
Sin embargo, después de pensar en esto un poco más, creo que la solución más simple y mejor es simplemente lanzar la cuerda dos veces (como sugiere el jathanismo ):
str(float(your_string_goes_here))
Edición: aclaración añadida debido a un comentario.
Actualizado generalizado para mantener la precisión y manejar valores 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
Salida:
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
''%.17g'' % float(mystr)
Dependiendo de lo que realmente quieras hacer ..