access variables in list python-CodePudding

I need to acess a variable in list for example

var1=[Orange,Banana]
var2=[Apple,Pear]
var3=[Banana,Pear]
var4=[Grapes,Orange]
var5=[Orange,Apple]

user_fruit = str(input("Whats ur favorite fruit?: "))

*user inputs Orange, Pear

How do I somehow print out var1, var2 var3, var5, (like print out all variable with the user's input within their lists'.

CodePudding user response：

You can achieve this using locals, although it is almost never a good idea. It is better to structure your data as a dict in the first place, e.g. {"var1": ["Orange", "Banana"]}.

var1=["Orange","Banana"]
var2=["Apple","Pear"]
var3=["Banana","Pear"]
var4=["Grapes","Orange"]
var5=["Orange","Apple"]

# dict of all locally defined variables that start with "var"
my_vars = {k: v for k, v in locals().items() if k.startswith("var")}
# {'var1': ['Orange', 'Banana'],
#  'var2': ['Apple', 'Pear'],
#  'var3': ['Banana', 'Pear'],
#  'var4': ['Grapes', 'Orange'],
#  'var5': ['Orange', 'Apple']}

# user_fruit = str(input("Whats ur favorite fruit?: "))
user_fruit = "Banana"

# print all varnames containing user_fruit
for k, v in my_vars.items():
  if user_fruit in v:
    print(k)
# prints var1 and var3

# for faster lookup, you can preprocess the data so that each fruit 
# encodes a list of vars containing it
from collections import defaultdict

fruit_to_var = defaultdict(list)
for k, v in my_vars.items():
  for fruit in v:
    fruit_to_var[fruit].append(k)

# another lookup:
print(fruit_to_var["Banana"])

CodePudding user response：

If you want just access to name of variables (for example Orange), you can define them as string in one list. Then for searching a name in list, You can do this:

user_input = str(input("Whats ur favorite fruit?: "))
mylist = ['Orange', 'Banana', 'Apple' ,'Pear']
print(mylist[mylist == user_input])

But if you want name of variable (and its value), this link can help you:

How can you print a variable name in python?

CodePudding user response：

I didn't understand your question. Could you please be more specific? What I have figured out, I tried to solve it. Here is the snippet.

var1 = ["Orange", "Banana"]
var2 = ["Apple", "Pear"]
var3 = ["Banana", "Pear"]
var4 = ["Grapes", "Orange"]
var5 = ["Orange", "Apple"]

newlst = [var1, var2, var3, var4, var5]

user_fruit = input("Whats ur favorite fruit?: ")
user_fruit = user_fruit.split(
    ", ") if ", " in user_fruit else user_fruit.split(",")

for fruit in user_fruit:
    for flist in newlst:
        if fruit in flist:
            print(flist)