解包错误

Question

    lstOfitems= list(leterCount.values())
    HstNumber = max(lstOfitems)
    ListOfkeys= list(leterCount.keys())
    NumberofChar = len(ListOfkeys)
    tess = turtle.Turtle()
    tess.color("white")
    tess.fillcolor("white")
    tess.pensize(3)
    wn = turtle.Screen()             
    wn.bgcolor("black")
    wn.setworldcoordinates(0-BORDER,0-BORDER,FORWARD*NumberofChar+BORDER,HstNumber+BORDER)
    for a,b in(lstOfitems,ListOfkeys):
        drawBar(tess, a, b)

The above code takes in a string and counts how many charters there are and stores then in a dictionary. I'm trying to then make a bar chart after that but i run in to the problem where i get an error saying there are to vaules to unpack. How do i fix this ?

the trace back is this :

Traceback (most recent call last):

File "C:\\Users\\Steven\\Desktop\\lab8excirse2.py", line 76, in main() File "C:\\Users\\Steven\\Desktop\\lab8excirse2.py", line 74, in main loopSTr() File "C:\\Users\\Steven\\Desktop\\lab8excirse2.py", line 47, in loopSTr for a,b in(lstOfitems,ListOfkeys): ValueError: too many values to unpack (expected 2)

Answer 1

I think, you want something like this:

 for b,a in leterCount.items():
    drawBar(tess, a, b)

Answer 2

Try changing (lstOfitems,ListOfkeys) to zip(lstOfitems,ListOfkeys) . (lstOfitems,ListOfkeys) is simply a tuple consisting of two list s, you cannot unpack it. However, Python's built-in zip function will return an iterator of tuples, where the i-th tuple contains the i-th element from each of the argument sequences or iterables; which is what you want.

But a better way to do this is to access the dictionary keys/value pairs using the dictionary's 'items method: for b,a in leterCount.items():`

Having said that, are you aware that Python collections has a dict sub-class called Counter that does pretty much what you want? You can use it like so:

from collections import Counter

c = Counter('gallahad') # a new counter from an iterable
# c will then be: Counter({'a': 3, 'l': 2, 'h': 1, 'g': 1, 'd': 1})