I have a nested dict:
KEYS1 = ("A", "B", "C")
KEYS2 = ("X", "Y", "Z")
d = dict.fromkeys(KEYS1, dict.fromkeys(KEYS2, 0))
I'd now like to embed its values in a string using format, something like
print("{A,X:d}".format(**d))
That does not work. Any suggestions on how to do this correctly?
print("d['A']['X']={A[X]}".format(**d))
Output:
d['A']['X']=0
From python 3.6 you will be able to access the dict in the string use Literal string interpolation:
In [23]: print(f"d['A']['X']={d['A']['X']}")
d['A']['X']=0
f"{d['A']['X']=}" (the trailing = sign is the key).You can take advantage of str.format's ability to do subscripting on the arguments you provide.
print("d['A']['X']={[A][X]}".format(d))
This is really similar to Padraic Cunningham's answer, which is also a good and correct way to do it. The difference is that in his answer, the part of the string {A[X]} means that the .format method is looking for a keyword argument, which gets provided by unpacking the dict d.
In my method, it is expecting a positional argument, which must be a dict with a key 'A', which must also be a dict with the key 'X'.
d = dict.fromkeys(KEYS1, dict.fromkeys(KEYS2, 0))- watch out. Every value in the outer dict is the same inner dict, so anything you do tod['A']will be visible throughd['B'].dictwith a genexp in Python <2.7.{key1: dict.fromkeys(KEYS2, 0) for key1 in KEYS1}, ordict((key1, dict.fromkeys(KEYS2, 0)) for key1 in KEYS1). In cases where the inner values also need to be distinct, you can replace the innerfromkeyswith a dict comprehension too.