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FaridMoussaoui
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Re: Python tricks

October 10th, 2019, 3:40 pm

that's python IDE is easier
 
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Cuchulainn
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Re: Python tricks

October 11th, 2019, 7:51 am

that's python IDE is easier
I sugested pyCharm. My student loves it! No looking back, goodbye VS and parallels for her. We keep the infrastructure threshold low. The rest is plain sailing.
Merci, Farid.
 
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Cuchulainn
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Re: Python tricks

October 17th, 2019, 1:56 pm

Is this a bug in Python?
import pandas as pd
from pandas import datetime, period_range

#compiles
#myRange = pd.period_range('2000-01-01', periods=12, freq='T')
#ts  = pd.Series(range(12), index=myRange)

#NOT compile
range = pd.period_range('2000-01-01', periods=12, freq='T')
ts  = pd.Series(range(12), index=range)

ts.index = ts.index.astype('datetime64[ns]')
data_higher_freq = ts.resample('5T').sum()
 
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FaridMoussaoui
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Re: Python tricks

October 17th, 2019, 2:52 pm

Is this a bug in Python?
Isn't python, it is the developer. What about using a square bracket instead of a parenthese .....
 
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Cuchulainn
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Re: Python tricks

October 17th, 2019, 4:51 pm

Even more interesting I accidentally had a range() function and this is the one that resample() sees. Ouch
Very bad.I am accidentally or deliberately overriding what is in essence an (undocumented) Python keyword 'range'.

Q: The ability to override core Python functions with impunity,feature or bug?

Code:
 
def range(i):
    print ("range")
    return 1/0

 
 
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Cuchulainn
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Re: Python tricks

October 17th, 2019, 4:58 pm

Is this a bug in Python?
Isn't python, it is the developer. What about using a square bracket instead of a parenthese .....
range is a function, not an object
?
 
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tagoma
Topic Author
Posts: 18363
Joined: February 21st, 2010, 12:58 pm

Re: Python tricks

October 20th, 2019, 8:49 am

Is this a bug in Python?
Isn't python, it is the developer. What about using a square bracket instead of a parenthese .....
range is a function, not an object
?
Python allows built-in functions overloading. Bad or good is mental masturbation. That's just the way it is. Programmer is supposed to have come through the list of these built-in functions at some point, and understands it is usually bad practice to use those name to create object/functions/etc. To somewhat circumvent the issue, programmer can use scope/namespace tricks.

import builtins
builtins.range(10)
#range(0, 10)


 
 
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Cuchulainn
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Re: Python tricks

October 20th, 2019, 9:56 am

Nice. So, one can put functions and so on in modules which is good practice. System decomposition into independent and loosely coupled modules is recommended before jumping head first into coding marathons.
 
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ISayMoo
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Re: Python tricks

November 1st, 2019, 4:45 pm

 
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tagoma
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Joined: February 21st, 2010, 12:58 pm

Re: Python tricks

November 23rd, 2019, 1:23 pm

Python 3.8 introduced the Walrus operator.
What are the cons according to you Wilmotters?
 
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Cuchulainn
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Re: Python tricks

February 14th, 2020, 4:18 pm

Am getting issues when installing packages in Pycharm, VS and Anaconda.
Any ideas?
Collecting clawpack
  Using cached clawpack-5.6.1.tar.gz (5.7 MB)
ERROR: The tar file (C:\Users\ABC\AppData\Local\Temp\pip-unpack-vv069ogw\clawpack-5.6.1.tar.gz) has a file (C:\Users\ABC1\AppData\Local\Temp\pip-install-3y0_4wxk\clawpack\pyclaw/
development/point_wise_rs/pyWrapperForRiemannSolver/aux.npy) trying to install outside target directory (C:\Users\ABC\AppData\Local\Temp\pip-install-3y0_4wxk\clawpack)
----- Failed to install 'clawpack' -----

 
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FaridMoussaoui
Posts: 507
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Re: Python tricks

February 14th, 2020, 6:35 pm

Who is user "ABC1"? a typo in your target directory?
 
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Cuchulainn
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Re: Python tricks

February 14th, 2020, 7:31 pm

Who is user "ABC1"? a typo in your target directory?
No, I changed the real name to ABC. That directory exists.

BTW my problem is well-known.

https://stackoverflow.com/questions/52949531/could-not-install-packages-due-to-an-environmenterror-errno-13/53916143
 
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FaridMoussaoui
Posts: 507
Joined: June 20th, 2008, 10:05 am
Location: Genève, Genf, Ginevra, Geneva

Re: Python tricks

February 14th, 2020, 7:57 pm

That's not the correct link. Your error arise in the pip file unpacking.py
 
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Cuchulainn
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Re: Python tricks

February 14th, 2020, 8:36 pm

That's not the correct link. Your error arise in the pip file unpacking.py
uh! Is that a bug in Python?
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