How to get key filtered by its value in multidimensional array Python-CodePudding

I got this data

employee_detail_list = {
      'John Doe': {
          'name': 'EMP-0001',
          'first_name': 'John',
          'last_name': 'Doe',
          'full_name': 'John Doe',
          'company': 'Company 1'
      },
      'Tom Smith': {
          'name': 'EMP-0002',
          'first_name': 'Tom',
          'last_name': 'Smith',
          'full_name': 'Tom Smith',
          'company': 'Company 2'
      },
      'Andrew Sebastian': {
          'name': 'EMP-0003',
          'first_name': 'Andrew',
          'last_name': 'Sebastian',
          'full_name': 'Andrew Sebastian',
          'company': 'Company 2'
      },   }

i want output

Tom Smith
Andrew Sebastian

by filtering value "Company 2", i've try this code:

# list out keys and values separately
key_list = list(employee_detail_list.keys())
val_list = list(employee_detail_list.values())

# print key with val Company 2
position = val_list.index("Company 2")
print(key_list[position])

but always ended up with this error:

ValueError: 'Company 2' is not in list

any thought what is wrong? thanks before

CodePudding user response：

It does what you need. .items() returns data as iterable objects that can be traversed.

for key, value in employee_detail_list.items():
    if value["company"] == "Company 2":
        print(key)

# Output
Tom Smith
Andrew Sebastian

The problem with your solution is that val_list = list(employee_detail_list.values()) returns a list with objects and you are trying to find val_list.index("Company 2") by string which is not there

CodePudding user response：

You can use filter()

employee_detail_list = {
      'John Doe': {
          'name': 'EMP-0001',
          'first_name': 'John',
          'last_name': 'Doe',
          'full_name': 'John Doe',
          'company': 'Company 1'
      },
      'Tom Smith': {
          'name': 'EMP-0002',
          'first_name': 'Tom',
          'last_name': 'Smith',
          'full_name': 'Tom Smith',
          'company': 'Company 2'
      },
      'Andrew Sebastian': {
          'name': 'EMP-0003',
          'first_name': 'Andrew',
          'last_name': 'Sebastian',
          'full_name': 'Andrew Sebastian',
          'company': 'Company 2'
      }
}

def isFromCompany2(data):
    return data["company"] == "Company 2"

result = filter(isFromCompany2, employee_detail_list.values())

print(list(result))

This is a nice article that explains it https://realpython.com/python-filter-function/