5

How to create new variables with names from list? This:

name = ['mike', 'john', 'steve']   
age = [20, 32, 19]  
index = 0

for e in name:
    name[index] = age[index]
    index = index+1

of course does not work. What should I do?

I want to do this:

print mike
>>> 20

print steve
>>> 19
user1496868
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    [You should keep data out of your variable names.](http://nedbatchelder.com/blog/201112/keep_data_out_of_your_variable_names.html) Use a dictionary instead. – Sven Marnach Jul 03 '12 at 22:12
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    Strongly agree with Sven. Don't do this. If you think you have an exceptionally good reason then (a) you probably don't but (b) tell us what it is just in case. (It can be done, but I urge anyone reading this not to explain how unless the OP has given a good enough reason.) – Gareth McCaughan Jul 03 '12 at 22:14
  • Well, i have a lot of widgets in pygtk (from glade), named: entry_name, entry_secondname, entry_age etc. Normally i import it like this: `self.entry_name = self.wTree.get_widget("entry_name")` `self.entry_secondname = self.wTree.get_widget("entry_secondname")` But i wanted to automatized it in loop. Wrong way? – user1496868 Jul 03 '12 at 22:26
  • @user1496868: If it's `self`, then you can assign to `self.__dict__[somename]` instead. – Ry- Jul 03 '12 at 22:35
  • Does this answer your question? [How do I create a variable number of variables?](https://stackoverflow.com/questions/1373164/how-do-i-create-a-variable-number-of-variables) – wjandrea Jul 02 '20 at 01:26

4 Answers4

12

I think dictionaries are more suitable for this purpose:

>>> name = ['mike', 'john', 'steve']   

>>> age = [20, 32, 19] 

>>> dic=dict(zip(name, age))

>>> dic['mike']
20
>>> dic['john']
32

But if you still want to create variables on the fly you can use globals()[]:

>>> for x,y in zip(name, age):
    globals()[x] = y


>>> mike
20
>>> steve
19
>>> john
32
Ashwini Chaudhary
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4

You can use globals():

globals()[e] = age[index]

Generally, though, you don't want to do that; a dictionary is much more convenient.

people = {
    'mike': 20,
    'john': 32,
    'steve': 19
}
Ry-
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  • No, you can't use `vars()`. See the documentation. It returns `locals()`, and the return value of `locals()` must not be modified. (It will work by chance if `locals()` happens to coincide with `globals()`.) – Sven Marnach Jul 03 '12 at 22:16
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    @SvenMarnach: Oops, thanks. It is now "fixed". Not that I recommend it anyways. – Ry- Jul 03 '12 at 22:19
0
name = ['mike', 'john', 'steve']   
age = [20, 32, 19] 
for i in range(len(name)):
    exec("%s = %d" %(name[i], age[i]))
print(mike)
print(john)
print(steve)
Fernando Wakabayashi
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A dictionary is the way to go!

import pandas as pd
import datetime
import pandas_datareader as dr

# Get data for this year, so far
start = datetime.datetime(2019,1,1)
end = datetime.datetime(2019,6,1)

companies = ['AA', 'AAPL', 'BA', 'IBM']
df_dict = {}
for name in companies:
    df_dict[name] = pd.DataFrame()
    df_dict[name] = dr.data.get_data_yahoo(name, start, end)

print()
print(' Apple dataframe ')
print(df_dict['AAPL'].head())
cobrp
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