Stuck again, this time my problem is getting the dictionary to be sorted in ascending order. Please Advise! the following is what the task says:
"""
A sparse vector is a vector whose entries are almost all zero, like [1, 0, 0, 0, 0, 0, 0, 2, 0]. Storing all those zeros wastes memory and dictionaries are commonly used to keep track of just the nonzero entries. For example, the vector shown earlier can be represented as {0:1, 7:2}, since the vector it is meant to represent has the value 1 at index 0 and the value 2 at index 7. Write a function that converts a dictionary back to its sparese vector representation.

Examples

    >>> convertDictionary({0: 1, 3: 2, 7: 3, 12: 4})
    [1, 0, 0, 2, 0, 0, 0, 3, 0, 0, 0, 0, 4]
    >>> convertDictionary({0: 1, 2: 1, 4: 2, 6: 1, 9: 1})
    [1, 0, 1, 0, 2, 0, 1, 0, 0, 1]
    >>> convertDictionary({})
    []

"""

I wrote the following:

def convertVector(numbers):
	t = []
	c = []
	h = len(numbers)
	for x in numbers:
		if x == 0:
			continue
		else:
			t.append(numbers.index(x)+ (h-len(numbers)))
			c.append(x)
			numbers.pop(numbers.index(x))
	return dict(zip(t,c))

which returns the correct results, but in the wrong order, i experimented with sort and sorted but it always messed up, how can i sort the dictionary as it is, without changing the results? seems i always get stuck at the easiest bits

Help appreciated.

Recommended Answers

You are not taking dictionary as input, this is the other direction? The dictionary has not order, so that does not matter.
[CODE]>>> def print_dictionary(d):
print '[%s]' % (', '.join('%s' % (0 if v not in d else d[v]) for v in range(min(d), max(d)+1)))

print_dictionary({0: 1, 2: …

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Re: Dictionary To Sparse Vector help- sort dictionary? 80 80

You are not taking dictionary as input, this is the other direction? The dictionary has not order, so that does not matter.

>>> def print_dictionary(d):
	print '[%s]' % (', '.join('%s' % (0 if v not in d else d[v]) for v in range(min(d), max(d)+1)))
	
>>> print_dictionary({0: 1, 2: 1, 4: 2, 6: 1, 9: 1})
[1, 0, 1, 0, 2, 0, 1, 0, 0, 1]
>>>
Re: Dictionary To Sparse Vector help- sort dictionary? 80 80

LOL, i realized my mistake, i hit submit and it went, but came back wanting the sparse vector, but i realized just now its just a very similar exercise, so i already completed the one before. Thanks for the help though!

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