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Objective-C for Windows
...hey should make a new badge for bs answers. No offense @michael. It's an interesting read.
– Wolfpack'08
May 13 '15 at 15:15
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How to form tuple column from two columns in Pandas
... lists rather than tuples)
import pandas as pd
import numpy as np
size = int(1e+07)
df = pd.DataFrame({'a': np.random.rand(size), 'b': np.random.rand(size)})
%timeit df.values.tolist()
1.47 s ± 38.9 ms per loop (mean ± std. dev. of 7 runs, 1 loop each)
%timeit list(zip(df.a,df.b))
1.92 s ± 1...
How does the “final” keyword in Java work? (I can still modify an object.)
...eference foo is binded to just one final object of ArrayList...it cannot point to any other ArrayList
– Code2Interface
Mar 27 '13 at 9:08
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What is the overhead of creating a new HttpClient per call in a WebAPI client?
...ltiple threads.
The HttpClientHandler has Credentials and Cookies that are intended to be re-used across calls. Having a new HttpClient instance requires re-setting up all of that stuff.
Also, the DefaultRequestHeaders property contains properties that are intended for multiple calls. Having to re...
Are global variables in PHP considered bad practice? If so, why?
...!pattern!', array($obj, 'method'), $str);
See callbacks for more.
The point is that objects have been bolted onto PHP and in some ways lead to some awkwardness.
Don't concern yourself overly with applying standards or constructs from different languages to PHP. Another common pitfall is trying t...
Use email address as primary key?
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String comparison is slower than int comparison. However, this does not matter if you simply retrieve a user from the database using the e-mail address. It does matter if you have complex queries with multiple joins.
If you store information about users in ...
Is there a “theirs” version of “git merge -s ours”?
When merging topic branch "B" into "A" using git merge , I get some conflicts. I know all the conflicts can be solved using the version in "B".
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__FILE__, __LINE__, and __FUNCTION__ usage in C++
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@thr: while you make a good point. I was pretty clear that __func__ exists in c99, not c++. Regardless, I think a reasonable implementation of __func__ in c++ would just result in the mangled name. Since I'm not a compiler writer, it's not really my call....
How do I return the response from an asynchronous call?
...on both sides with resume, filereader, filesystem), various image resizers converters using canvas, populate web SQL databases with base64images and much more... But in these cases you should create a function only for that purpose... sometimes you need a blob, array buffers, you can set headers, ov...
Overloading member access operators ->, .*
...mber lookup.
If the return value is another object of class type, not a pointer, then the subsequent member lookup is also handled by an operator-> function. This is called the "drill-down behavior." The language chains together the operator-> calls until the last one returns a pointer.
stru...