Python: Unterschied zwischen den Versionen

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isStringOrSubclass = isinstance(aVariable, str)
isStringOrSubclass = isinstance(aVariable, str)
isString = type(aVariable) is str
isString = type(aVariable) is str
== Formatierung ==
"{:3.7f} {:s} {:07d}".format(3.14, "hello", 100)
"{0:d} / {0:x}".format(714)

Version vom 4. März 2013, 03:03 Uhr

Datentypen

  • List: ['a', 1]; x[1] = 5
  • Tupel: ('a', 1), ro

Spezielle Methoden/Attribute

  • Statische Methoden:
class X:
   @staticmethod
   def doIt(param):
      pass

X.doIt(True)
  • Feststellen, ob Attribut existiert: hasattr(instance, nameOfAttribute)

Dictionary

x = { 'key' : 'val', 'xyz': 3 }
x['key'] = value
del x['key'];
contains = 'key' in x and 'key2' not in x
size = len(x)
for pair in x.iteritems():
  key = pair[0]
for key in x.iterkeys():
  print key
  • x.itervalues()
  • x.setdefault(key[, value]): setzt Wert nur, wenn noch nicht gesetzt
  • x.keys(), x.values()
  • x.copy(): flache Kopie
  • x.update(dict): addiert dict zu x

Mengen

s = set(['y', 3]) ; f = frozenset(['y', 3]) 
for elem in s:
  print elem
size = len(s)
contains = 3 in s and 4 not in s
intersection = s & f
union = s | f
isPartOf = s <= f
diff = s - f

Dateien

with open(self._filename, "r") as fp:
  for line in fp:
     print line
fp.close()

Typcheck

isStringOrSubclass = isinstance(aVariable, str)
isString = type(aVariable) is str

Formatierung

"{:3.7f} {:s} {:07d}".format(3.14, "hello", 100) "{0:d} / {0:x}".format(714)