PythonTutorial
Version vom 19. August 2016, 13:11 Uhr von Hamatoma (Diskussion | Beiträge) (Die Seite wurde neu angelegt: „Kategorie:Sprache Kategorie:Tutorial == Using the Interpreter Interactive == <pre> Calculator: 2*5.0+(3-2**17) % 12 Storing in a variable: a=2**31 ; l…“)
Using the Interpreter Interactive
Calculator: 2*5.0+(3-2**17) % 12
Storing in a variable: a=2**31 ; len(str(a))
Using mathematical functions:
import math ; math.log10(2**63)
“unlimited” integers: 10**80
Method:
def fib(n) : return 1 if n <= 1 else fib(n-1) + fib(n-2)
Loop:
for x in range(10) : print('x: {:d} fib: {:d}'.format(x, fib(x)))
Important Types: list:
List: mixed types, mutable aList = [1, 2, 5, 'a string'] ; aList.append([3.0]) ; aList += ['x'] ; aList Parts: aList[3:] ; aList[:3] ; aList[1:3] ; b = [aList[2], aList[5]] ; b Replace: x=[1, 2, 3, 4, 5] ; x[0] = 'A2' ; x[1:3] = ['b2', 'c2'] ; x Variables are references: x=[1, 2, 3] ; y = x ; y[1] = 'x' ; x ; y Copy a list “deeply”: x=[1, 2, 3] ; y = x[:] ; y[1] = 'x' ; x ; y
Important Types: tuple, dict
Tuple: immutable, different types
t = (1, 2, 'x') ; t
Dictionary (Hashtable): mutable
d = dict() ; d['abc'] = 22 ; d
d = { 22 : 'xy', 33 : 'z' } ; d[22] ; d
d.keys() ; d.values()
Iterator:
for key in d.keys():
print('key: {:d} val: {:s}'.format(key, d[key]))