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Apply pandas function to column to create multiple new columns?
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I usually do this using zip:
>>> df = pd.DataFrame([[i] for i in range(10)], columns=['num'])
>>> df
num
0 0
1 1
2 2
3 3
4 4
5 5
6 6
7 7
8 8
9 9
>>> def powers(x):
>...
NSOperation vs Grand Central Dispatch
...ed first, but as of 10.5 and iOS 2, NSOperationQueue and friends are internally implemented using GCD.
In general, you should use the highest level of abstraction that suits your needs. This means that you should usually use NSOperationQueue instead of GCD, unless you need to do something that NSOp...
Build fat static library (device + simulator) using Xcode and SDK 4+
It appears that we can - theoretically - build a single static library that includes both simulator and iPhone and iPad.
10...
How to add an empty column to a dataframe?
... with .reindex(rows=[...]). Note that newer versions of Pandas (v>0.20) allow you to specify an axis keyword rather than explicitly assigning to columns or rows.
Here is an example adding multiple columns:
mydf = mydf.reindex(columns = mydf.columns.tolist() + ['newcol1','newcol2'])
or
mydf...
Convert int to char in java
...a + '0');
System.out.println(b);
Here, we used '0' because chars are actually represented by ASCII values. '0' is a char and represented by the value of 48.
We typed (a + '0') and in order to add these up, Java converted '0' to its ASCII value which is 48 and a is 1 so the sum is 49. Then what w...
How can I override the OnBeforeUnload dialog and replace it with my own?
...e removed or altered.
The problem seems to be:
When onbeforeunload is called, it will take the return value of the handler as window.event.returnValue.
It will then parse the return value as a string (unless it is null).
Since false is parsed as a string, the dialogue box will fire, which will t...
Disadvantages of Test Driven Development? [closed]
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Several downsides (and I'm not claiming there are no benefits - especially when writing the foundation of a project - it'd save a lot of time at the end):
Big time investment. For the simple case you lose about 20% of the actual implementation, but for complicated cases you lose much more.
Ad...
Populating a database in a Laravel migration file
...anges consistently so that you can for example deploy to staging, see that all is well, and then deploy to production with confidence of the same results (and not have to remember to run some manual step).
However, there is still value in separating out the seed and the migration as those are two r...
Copy a variable's value into another
...t.
Any change you make to the contents of this object will be seen identically whether you reference it through the a variable or the b variable. They are the same object.
So, when you later try to "revert" b to the original a object with this code:
b = a;
The code actually does nothing at all,...
SQL Server Management Studio, how to get execution time down to milliseconds
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The part regarding the Properties window is really the answer to this thread. "Elapsed Time" is sitting there staring you in the face.
– Eric
Jan 20 '15 at 23:32
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