python - ajout des valeurs d'un dictionnaire à une liste - Stack Overflow

Hi I am having a bit of difficulty adding tuples which are the values of a dictionary I have extracted the tuples and need to added to an iterable item say an empty list. i.e.

path = [1,2,3,4]
pos = {1:(3,7), 2(3,0),3(2,0),4(5,8)}
h = []
for key in path:
     if key in pos:
     print pos[key]
     h.append(pos[Key])#Gives an error

Please how can i append the values in pos[key] into a h. Thanks

You can use list comprehension:

h = [pos[key] for key in path if key in pos]

Demo:

print h
>>> [(3, 7), (3, 0), (2, 0), (5, 8)]

Notes:

• A dictionary should be declared like pairs of key:value. Your syntax is incorrect.


• Also, Python is case-sensitive so key is different than Key.

Several problems here:

• wrong syntax on the pos = {1:(3,7), 2(3,0),3(2,0),4(5,8)} line, watch colons


• indentation, the if block should be indented


• variables in python are case-sensitive, there is no Key variable defined, you probably meant key instead

Here's the code with fixes:

path = [1,2,3,4]
pos = {1:(3,7), 2:(3,0),3:(2,0),4:(5,8)}
h = []
for key in path:
     if key in pos:
         print pos[key]
         h.append(pos[key])

After running the code, h will be equal to:

[(3, 7), (3, 0), (2, 0), (5, 8)]

Hope that helps.

Hi I am having a bit of difficulty adding tuples which are the values of a dictionary I have extracted the tuples and need to added to an iterable item say an empty list. i.e.

path = [1,2,3,4]
pos = {1:(3,7), 2(3,0),3(2,0),4(5,8)}
h = []
for key in path:
     if key in pos:
     print pos[key]
     h.append(pos[Key])#Gives an error

Please how can i append the values in pos[key] into a h. Thanks

You can use list comprehension:

h = [pos[key] for key in path if key in pos]

Demo:

print h
>>> [(3, 7), (3, 0), (2, 0), (5, 8)]

Notes:

• A dictionary should be declared like pairs of key:value. Your syntax is incorrect.


• Also, Python is case-sensitive so key is different than Key.

Several problems here:

• wrong syntax on the pos = {1:(3,7), 2(3,0),3(2,0),4(5,8)} line, watch colons


• indentation, the if block should be indented


• variables in python are case-sensitive, there is no Key variable defined, you probably meant key instead

Here's the code with fixes:

path = [1,2,3,4]
pos = {1:(3,7), 2:(3,0),3:(2,0),4:(5,8)}
h = []
for key in path:
     if key in pos:
         print pos[key]
         h.append(pos[key])

After running the code, h will be equal to:

[(3, 7), (3, 0), (2, 0), (5, 8)]

Hope that helps.

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