geerk / c45algorithm Goto Github PK

sklearn has no decent tree implementation.

Hi! Thank you for sharing your implementation of C4.5 (over 10 years ago!!)

I just wanted to point out a simple fix that can improve by order of magnitudes the runtime of the algorithm, in some datasets. I hope this will be useful for people like me that will find this repo in the future.

return {k: [v[i] for i in range(len(v)) if i in ind] for k, v in t.items()}

Here, it is useless to cycle over range and ind. You can simplify as follows:

return {k: [v[i] for i in ind] for k, v in t.items()}

On my machine, running the updated version on the mushroom UCI dataset takes <1s, while before it took about 50 seconds.

I plan to release a repository that will include your updated code. (hoping that's ok!)
Thanks!

Traceback (most recent call last):
File "c45test.py", line 2, in
from c45 import *
File "/home/s1617346/Desktop/C45algorithm-master/c45.py", line 2, in
import utils
File "/home/s1617346/Desktop/C45algorithm-master/utils.py", line 42
return {k: [v[i] for i in range(len(v)) if i in ind] for k, v in t.items()}
^
SyntaxError: invalid syntax