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How to create a new branch from a tag?
I'd like to create a new master branch from an existing tag. Say I have a tag v1.0 . How to create a new branch from this tag?
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Redirecting to URL in Flask
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You have to return a redirect:
import os
from flask import Flask,redirect
app = Flask(__name__)
@app.route('/')
def hello():
return redirect("http://www.example.com", code=302)
if __name__ == '__main__':
# Bind to PORT if defined, otherwise default to 500...
Can anyone explain python's relative imports?
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You are importing from package "sub". start.py is not itself in a package even if there is a __init__.py present.
You would need to start your program from one directory over parent.py:
./start.py
./pkg/__init__.py
./pkg/parent.py
./pkg/sub...
cartesian product in pandas
... you can produce a cartesian product using merge (like you would in SQL).
from pandas import DataFrame, merge
df1 = DataFrame({'key':[1,1], 'col1':[1,2],'col2':[3,4]})
df2 = DataFrame({'key':[1,1], 'col3':[5,6]})
merge(df1, df2,on='key')[['col1', 'col2', 'col3']]
Output:
col1 col2 col3
0 ...
Returning first x items from array
I want to return first 5 items from array. How can I do this?
5 Answers
5
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How to return an array from JNI to Java?
...sed of an 'Object' array creating with the JNI function NewObjectArray(). From the perspective of JNI, that's all a two dimensional array is, an object array containing a number of other inner arrays.
The following for loop creates the inner arrays which are of type int[] using the JNI function ...
From ND to 1D arrays
...contiguous in memory, but would return a copy if, for example, a were made from slicing another array using a non-unit step size (e.g. a = x[::2]).
If you want a copy rather than a view, use
In [15]: c = a.flatten()
If you just want an iterator, use np.ndarray.flat:
In [20]: d = a.flat
In [21]...
How do I check if there are duplicates in a flat list?
... Denis Otkidach offered a solution where you just build a new set from the list, then check its length. Its advantage is that it's letting the C code inside Python do the heavy lifting. Your solution loops in Python code, but has the advantage of short-circuiting when a single match has b...
Why is it slower to iterate over a small string than a small list?
...ter strings are cached.
The difference is unobvious, but is likely created from a greater number of checks on string indexing, with regards to the type and well-formedness. It is also quite likely thanks to the need to check what to return.
List indexing is remarkably fast.
>>> python...
Delete rows from a pandas DataFrame based on a conditional expression involving len(string) giving K
I have a pandas DataFrame and I want to delete rows from it where the length of the string in a particular column is greater than 2.
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