Question

does anyone know what this does, ...

freq = {}
for x in sequence:
freq[x] = freq.get(x,0) + 1
return freq

Thanks.

Answer 1

In what language? What is sequence? Is it a standard thing in that language?

Answer 2

Because you set freq to some sort of empty set or mapping, then go to for x in sequence... well, I don't see sequence defined....

Answer 3

freq = {} # initiates a dictionary
for x in sequence: # will iterate all elements of sequence, no matter the type
freq[x] = freq.get(x,0) + 1 # will associate key x of dictionary freq to the value of get(x,0)+1:
#+if key x is found in freq, its value is returned, if not - 0 is returned
return freq # returns the entire dictionary freq

Answer 4

And what does it do if sequence is undefined?

Answer 5

well, probably shell throws out an error like: 'sequence undefined' :)

Answer 6

But here the sequence type is not so relevant as Python can iterate any iterable element.

Answer 7

Thanks!