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How to deal with SettingWithCopyWarning in Pandas?
...me.
Try using .loc[row_indexer,col_indexer] = value instead
df2
A
0 2.5
1 4.5
2 3.5
There are a couple ways of directly silencing this warning:
Make a deepcopy
df2 = df[['A']].copy(deep=True)
df2['A'] /= 2
Change pd.options.mode.chained_assignment
Can be set to None, "warn", or "raise...
What is the performance of Objects/Arrays in JavaScript? (specifically for Google V8)
...You can see this effect very nicely, this is from Chrome:
16: 4ms
40: 8ms 2.5
76: 20ms 1.9
130: 31ms 1.7105263157894737
211: 14ms 1.623076923076923
332: 55ms 1.5734597156398105
514: 44ms 1.5481927710843373
787: 61ms 1.5311284046692606
1196: 138ms 1.5196950444726811
1810: 139ms 1.5133779264214047
27...
What is the correct answer for cout
...P0145R3 Refining Expression Evaluation Order for Idiomatic C++ for more details.
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What is the dependency inversion principle and why is it important?
... should depend upon abstractions.
Abstractions should never depend upon details. Details should depend upon abstractions.
As to why it is important, in short: changes are risky, and by depending on a concept instead of on an implementation, you reduce the need for change at call sites.
Effectivel...
Nearest neighbors in high-dimensional data?
...for a polar coordinate system is a good idea (e.g., London to Vienna is is 2.5 hours, Vienna to St. Petersburg is another 3 hrs, more or less in the same direction, yet London to St. Petersburg isn't 5.5 hours, instead, is a little over 3 hrs.)
But apart from those cases in which your data belongs ...
How to enable local network users to access my WAMP sites?
...See the end of this post for how to do this in WAMPServer 3
For WampServer 2.5 and previous versions
WAMPServer is designed to be a single seat developers tool. Apache is therefore configure by default to only allow access from the PC running the server i.e. localhost or 127.0.0.1 or ::1
But as it i...
How efficient is locking an unlocked mutex? What is the cost of a mutex?
...ens often, then multiple locks would increase parallelism. At the cost of maintainability, since more locking means more debugging of the locking.
How efficient is it to lock a mutex? I.e. how much assembler instructions are there likely and how much time do they take (in the case that the mutex...
Why isn't `int pow(int base, int exponent)` in the standard C++ libraries?
... were more or less expecting this.
Then, I let x be constant (I set it to 2.5), and I looped n from 0 to 19 a hundred million times. This time, quite unexpectedly, glibc pow won, and by a landslide! It took only 2.0 user seconds. My pown took 9.6 seconds, and pown_l took 12.2 seconds. What happened...
How to calculate moving average using NumPy?
...5., 16., 17., 18.])
>>> moving_average(a, n=4)
array([ 1.5, 2.5, 3.5, 4.5, 5.5, 6.5, 7.5, 8.5, 9.5,
10.5, 11.5, 12.5, 13.5, 14.5, 15.5, 16.5, 17.5])
So I guess the answer is: it is really easy to implement, and maybe numpy is already a little bloated wit...
Why are C# 3.0 object initializer constructor parentheses optional?
...new[] { 1, 10, 100, 1000 }; // int[]
var b = new[] { 1, 1.5, 2, 2.5 }; // double[]
var c = new[] { "hello", null, "world" }; // string[]
var d = new[] { 1, "one", 2, "two" }; // Error
Reference: http://msdn.microsoft.com/en-us/library/ms364047%28VS.80%29.aspx
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