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pandas GroupBy columns with NaN (missing) values
...the same placeholder hack).
However, as described in another answer, from pandas 1.1 you have better control over this behavior, NA values are now allowed in the grouper using dropna=False
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A valid provisioning profile for this executable was not found for debug mode
...> clean all targets.
2) In "Groups & Files" -->Target --> expand it --> right click your app and select Clean "your app"
3) Goto->Window-->Organizer
4) In the Devices tab on the left, select your iphone
5) In the Provisioning section of the selected iphone delete all the cu...
Mac SQLite editor [closed]
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Hangs on slow running queries and had no cancel query button. I use RazorSQL.
– wioota
Jan 3 '09 at 17:49
2
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Logic to test that 3 of 4 are True
I want to return True if and only if 3 out of 4 boolean values are true.
27 Answers
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How to remove item from list in C#?
...s {
public int ID; public string FirstName; public string LastName;
}
and assigned some values to results as follows:
var results=new List<myClass> {
new myClass() { ID=1, FirstName="Bill", LastName="Smith" },
new myClass() { ID=2, FirstName="John", LastName="Wilson" },
new ...
How to backup a local Git repository?
I am using git on a relatively small project and I find that zipping the .git directory's contents might be a fine way to back up the project. But this is kind of weird because, when I restore, the first thing I need to do is git reset --hard .
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What are Transient and Volatile Modifiers?
Can someone explain what the transient and volatile modifiers mean in Java?
4 Answers
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What's the best way to check if a file exists in C?
...exists
} else {
// file doesn't exist
}
You can also use R_OK, W_OK, and X_OK in place of F_OK to check for read permission, write permission, and execute permission (respectively) rather than existence, and you can OR any of them together (i.e. check for both read and write permission using R...
Cleaner way to update nested structures
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Zippers
Huet's Zipper provides convenient traversal and 'mutation' of an immutable data structure. Scalaz provides Zippers for Stream (scalaz.Zipper), and Tree (scalaz.TreeLoc). It turns out that the structure of the zipper is automatically derivable from the original data str...
'const int' vs. 'int const' as function parameters in C++ and C
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const T and T const are identical. With pointer types it becomes more complicated:
const char* is a pointer to a constant char
char const* is a pointer to a constant char
char* const is a constant pointer to a (mutable) char
In o...