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Replace all non-alphanumeric characters in a string
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answered Oct 20 '12 at 5:11
nneonneonneonneo
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Increasing the timeout value in a WCF service
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Passing command line arguments in Visual Studio 2010?
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Get the name of the currently executing method
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How does the const constructor actually work?
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85
Const constructor creates a "canonicalized" instance.
That is, all constant expressions begin c...
converting drawable resource image into bitmap
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poitroaepoitroae
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How do I declare and initialize an array in Java?
...d(0, 100).toArray(); // From 0 to 100
int [] myIntArray = IntStream.of(12,25,36,85,28,96,47).toArray(); // The order is preserved.
int [] myIntArray = IntStream.of(12,25,36,85,28,96,47).sorted().toArray(); // Sort
For classes, for example String, it's the same:
String[] myStringArray = new Strin...
Create a variable name with “paste” in R?
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125
You can use assign (doc) to change the value of perf.a1:
> assign(paste("perf.a", "1", sep="...
Rename Pandas DataFrame Index
...so here are some more examples:
In [1]: df = pd.DataFrame([[1, 2, 3], [4, 5 ,6]], columns=list('ABC'))
In [2]: df
Out[2]:
A B C
0 1 2 3
1 4 5 6
In [3]: df1 = df.set_index('A')
In [4]: df1
Out[4]:
B C
A
1 2 3
4 5 6
You can see the rename on the index, which can change...
Assign multiple columns using := in data.table, by group
...1 hi hello
# 2: 2 2 hi hello
# 3: 3 3 hi hello
# 4: 1 4 hi hello
# 5: 2 5 hi hello
# 6: 3 6 hi hello
x[ , c("mean", "sum") := list(mean(b), sum(b)), by = a][]
# a b col1 col2 mean sum
# 1: 1 1 hi hello 2.5 5
# 2: 2 2 hi hello 3.5 7
# 3: 3 3 hi hello 4.5 9
# 4: 1 4 h...