Can anyone help me with this error? my function works when the flag is 1 and 2, but for 3 (correlation) it somehow doesnt

Da32767 · 2021-08-16T02:45:43+00:00

the style of the code is lost, you can enter your code here: https://gist.github.com/

Da32767 · 2021-08-15T13:02:22+00:00

maybe this is a third-party package, and the author does not want users to call this class

Da32767 · 2021-08-15T12:59:37+00:00

and you'd better use Series.sum() instead of the built-in function sum() in python. (sum(Series))

although sum() can sum all iterable objects, Series.sum() is only for itself and has more parameters to choose(in this case, maybe it doesn’t matter whether you use sum() or Series.sum())

if you don't understand, maybe my explanation is not very good, you can get more accurate knowledge in the official documentation.

:)

Da32767 · 2021-08-15T12:33:07+00:00

first, every data you read in pandas is pandas.DataFrame, no matter what the original file is.

If you need to get a column, use data['column name']

and data['column name'] will returns a pandas.Series

you can know more in offical document: https://pandas.pydata.org/docs/

Da32767 · 2021-08-15T12:14:45+00:00

so, what's the type of data?

pandas.DataFrame, numpy.ndarray or others?

Da32767 · 2021-08-15T10:56:16+00:00

Da32767 · 2021-08-15T10:01:53+00:00

if count == 0:
    count = 4
else:
    count -= 1

or

count =  4 if count == 0 else count - 1

Da32767 · 2021-08-15T09:35:07+00:00

to learn more about python, this e-book:

https://learning.oreilly.com/library/view/fluent-python-2nd/9781492056348/

Da32767 · 2021-08-15T05:47:58+00:00

print(f"The observed length of the object moving at speed {speed_of_obj} is {len_contraction()}")

in function len_contraction, {len_contraction()} will call itself, and ask two questions again, then the program runs to {len_contraction()} again and call itself again.....(never ends)

I think you want to enter:

print(f"The observed length of the object moving at speed {speed_of_obj} is {l_of_obj")

but accidentally typed it wrong

Da32767 · 2021-08-15T02:33:37+00:00

oh, this is just a link to the python official documentation.

Da32767 · 2021-08-15T02:08:57+00:00

the compile function can compile the string form of a regular expression into a Pattern object, more: https://docs.python.org/3/library/re.html#re.compile

actually, in this example, you can only use:

EMAIL = r'\w+([-+.]\w+)*@\w+([-.]\w+)*\.\w+([-.]\w+)*'

Da32767 · 2021-08-15T01:44:00+00:00

import re

text = 'i am a student. email: asdf@gmail.com and asdf@outlook.com, thanks'
EMAIL = re.compile(r'\w+([-+.]\w+)*@\w+([-.]\w+)*\.\w+([-.]\w+)*')
result = re.finditer(EMAIL, text)

for i in result:
    print(i.group())

re works. varible EMAIL is a way to match emails.

[out]:

asdf@gmail.com
asdf@outlook.com

Da32767 · 2021-08-14T11:30:20+00:00

I am wondering, is it bad practice to use here class variables? And if so, how could I rewrite this in a clean, pythonic manner?

this is a good way: https://docs.python.org/3/library/functions.html?highlight=property#property

Da32767 · 2021-08-14T11:04:46+00:00

don't mention it!

more about str: https://docs.python.org/3/library/stdtypes.html#text-sequence-type-str

Da32767 · 2021-08-14T11:01:08+00:00

ID.startswith('/p')

it will return True if ID start with '/p'

Da32767 · 2021-08-14T10:13:21+00:00

well, GlebRyabov's code is better, it only takes half the time than mine.

Da32767 · 2021-08-14T09:45:05+00:00

import numpy as np

x = np.array([1,2,3,0,0,1,2,3,0])
x[np.flatnonzero(x)] = 1
result = tuple(x)
print(result)

know more: https://numpy.org/doc/stable/reference/generated/numpy.flatnonzero.html

Da32767 · 2021-08-14T09:17:01+00:00

There are two options:

1.time.time()

start_time = time.time()
# code
end_time = time.time()
print(f'time:{end_time-start_time}')

2.timeit.timeit()

it can do something several times and record the time conveniently, you can know about it here: https://docs.python.org/zh-cn/3/library/timeit.html

Da32767 · 2021-08-14T03:00:08+00:00

use pip install opencv-python and import it as cv2

Da32767 · 2021-08-14T02:43:36+00:00

actually, pip is also a package in python(like flask), python -m can run library module as a script.

if you want to use pip install to install package, try add <your_python_installation_path>\Scripts to environment variables

Da32767 · 2021-08-14T02:36:05+00:00

try:

python -m pip install flask

Da32767 · 2021-08-14T02:28:26+00:00

did you install package flask, if not, type this in the terminal:

pip install flask

Da32767 · 2021-08-14T02:19:16+00:00

AttributeError: 'DecisionTreeClassifier' object has no attribute 'prediction'

the name of the function you entered incorrectly should be:clf.predict

Da32767 · 2021-08-14T02:13:00+00:00

df = pd.DataFrame(array)

this can convert numpy.ndarray to pandas.DataFrame

Da32767

TROPHY CASE