CODEWITHSUNDEEP
python
Krista Lane
Krista Lane

Reputation: 1

How can I create a list of strings from two other lists in Python?

I'm trying to create a list of strings where each element looks like "TEMP1996_U". The year (1996 in this case) comes from a list of years and the type (U in this case) comes from a list of strings. I want the list to have every combination of year and type.

To get a list with just year, I know I can do this:

years = range(1990,2000)
type_c = ["U", "R", "K", "B"]
temp_list = map('TEMP{0}'.format, years)

Can I add type_c on to this list in a similar way?

Upvotes: 0

Views: 71

Answers (3)

seralouk
seralouk

Reputation: 33137

A second way (in addition to Alex Hall's answer) could be the following:

years = range(1990,2000)
type_c = ["U", "R", "K", "B"]

temp_list = []
for i in years:
    for j in type_c:
        temp_list.append("TEMP%s_%s" % (i,j))

Upvotes: 1

johan d
johan d

Reputation: 2863

You can use list comprehension for this task:

temp_list = ['TEMP{0}_{1}'.format(y, t) for y in years for t in type_c]

It's quite clear and straightforward. That's where python really shines: Simple stuff done simply!

years = range(1990,2000)
type_c = ["U", "R", "K", "B"]
temp_list = ['TEMP{0}_{1}'.format(y, t) for y in years for t in type_c]
print (temp_list)

Upvotes: 1

Alex Hall
Alex Hall

Reputation: 36013

from itertools import product, starmap

years = range(1990, 2000)
type_c = ["U", "R", "K", "B"]
temp_list = list(starmap('TEMP{0}_{1}'.format, product(years, type_c)))
print(temp_list)

Output:

['TEMP1990_U', 'TEMP1990_R', 'TEMP1990_K', 'TEMP1990_B', 'TEMP1991_U', 'TEMP1991_R', 'TEMP1991_K', 'TEMP1991_B',
 'TEMP1992_U', 'TEMP1992_R', 'TEMP1992_K', 'TEMP1992_B', 'TEMP1993_U', 'TEMP1993_R', 'TEMP1993_K', 'TEMP1993_B',
 'TEMP1994_U', 'TEMP1994_R', 'TEMP1994_K', 'TEMP1994_B', 'TEMP1995_U', 'TEMP1995_R', 'TEMP1995_K', 'TEMP1995_B',
 'TEMP1996_U', 'TEMP1996_R', 'TEMP1996_K', 'TEMP1996_B', 'TEMP1997_U', 'TEMP1997_R', 'TEMP1997_K', 'TEMP1997_B',
 'TEMP1998_U', 'TEMP1998_R', 'TEMP1998_K', 'TEMP1998_B', 'TEMP1999_U', 'TEMP1999_R', 'TEMP1999_K', 'TEMP1999_B']

Upvotes: 4

Related Questions