1/22/2014

(python study) about dictionary variable (example source code)

__author__ = 'mare'

d = dict(a=1, b=3, c=5)
#{'a': 1, 'c': 5, 'b': 3}
type(d)
#< type 'dict'>

color = {"apple":"red", "banana":"yellow"}
#{'apple': 'red', 'banana': 'yellow'}

print( color["apple"] )
#red

#color[0] is not support, error

#color += {"cherry":"red"} -> error
color["cherry"] = "red"
#{'cherry': 'red', 'apple': 'red', 'banana': 'yellow'}
color["apple"] = "green"
#{'cherry': 'red', 'apple': 'green', 'banana': 'yellow'}

#items(), keys(), values()

for c in color.items():
 print(c)
#('apple', 'green')
#('cherry', 'red')
#('banana', 'yellow')

print('--')

for k, v in color.items():
 print(k, v)
#apple green
#cherry red
#banana yellow

print('--')

for k in color.keys():
 print(k)
#apple
#cherry
#banana

print('--')

for v in color.values():
 print(v)
#green
#red
#yellow

del color['cherry']
print(color)

color.clear()
#{'apple': 'green', 'banana': 'yellow'}

print(color)
#{}

#more complex
s = {'age':40.5, 'job':[1, 2, 3], 'name':{'kim':2, 'Cho':1}}
print(s)
#{'name': {'Cho': 1, 'kim': 2}, 'age': 40.5, 'job': [1, 2, 3]}