Py Loops (Ud.10.Apps)

Question 1

how to run a for-loop for a dict’s key and value?

Answer 1

]] for key, value in dict_1.items():

]] …

Question 2

how to print the dict’s key and value in a way compatible with Python version 3.6?

Answer 2

]] print(“%s: %s” % (key, value))

Question 3

how to replace a char in a string with another char?

Answer 3

]] phone_numbers = {“John Smith”: “+37682929928”,
“Marry Simpons”: “+423998200919”}
]] for key, value in phone_numbers.items():
]] print( value.replace(‘+’,’00’,))

Question 4

give an example of when to use ‘break’ and ‘continue’

Answer 4

while loops
]] while True:
]] username = input( 'Enter username')
]] if username == 'pypy':
]]       break
]]  else:
]]        continue

Question 5

how to run a for-loop for a dict’s values only?

Answer 5

]] for val in dict_1.values():

Question 6

how to run a for-loop for a dict’s keys only?

Answer 6

]] for val in dict_1.keys():

Question 7

how can strings from a list be concatenated in a print?

Answer 7

]] results[ ‘string1’, ‘string2’, ‘string3’ ]
]] print(“ “.join( results ))

– see note in Udemy 10 App course

Question 8

how can a return statement return a capitalized text string?

Answer 8

]] return “{ }.”.format( capitalized )

– from Udemy 10 App, when explaining the app

Question 9

what is the syntax of defining a for-loop? e.g. dividing values with 10

Answer 9

]] def for_1( lst )

]] new_lst = [i/10 for i in lst]

Question 10

what is the purpose of an in-line for-loop/list comprehension?

Answer 10

to transform traversed values in a list without storing the new values in a new list, the code is a more compressed way to do the same; 1 line of code instead of 3

Question 11

how can an an if-statement be added to the same in-line for-loop? e.g. only for values > 0

Answer 11

]] def for_1( lst )

]] new_lst = [ i/10 for i in lst if i > 0 ]

Question 12

how can an an if-else-statement be added to the same in-line for-loop? e.g. only for values > 0

Answer 12

]] def for_1( lst )

]] new_lst = [ i/10 if i > 0 else -1 for i in lst ]

Question 13

placeholder: isinstance

Answer 13

– pending

Question 14

how to create a function with an arbitrary number of non-key arguments?

Answer 14

]] def fn_arb( *args )

Question 15

how to create a function with an arbitrary number of key arguments? is it arbitrary?

Answer 15

]] def fn_arb( **args )

– no, because the number of args are defined

Question 16

what types will be created from a function with arbitrary list of non-key and key args?

Answer 16

tuple, dictionary

Question 17

is there anything to especially consider in the construction of ta function with an arbitrary number of key-args?

Answer 17

yes, each arg needs to be assigned a variable; a=1, b=2, etc.

Question 18

how to define a function with an argument having a default value?

Answer 18

]] def my_fn( radius = 27, diameter )