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How to get first character of string?
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1080
What you want is charAt.
var x = 'some string';
alert(x.charAt(0)); // alerts 's'
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How to extract text from a string using sed?
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The pattern \d might not be supported by your sed. Try [0-9] or [[:digit:]] instead.
To only print the actual match (not the entire matching line), use a substitution.
sed -n 's/.*\([0-9][0-9]*G[0-9][0-9]*\).*/\1/p'
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Default value to a parameter while passing by reference in C++
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104
You can do it for a const reference, but not for a non-const one. This is because C++ does not ...
Conditional Replace Pandas
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.ix indexer works okay for pandas version prior to 0.20.0, but since pandas 0.20.0, the .ix indexer is deprecated, so you should avoid using it. Instead, you can use .loc or iloc indexers. You can solve this problem by:
mask = df.my_channel > 20000
column_name = 'my_chann...
pyplot scatter plot marker size
...xamples and the output they produce.
# doubling the width of markers
x = [0,2,4,6,8,10]
y = [0]*len(x)
s = [20*4**n for n in range(len(x))]
plt.scatter(x,y,s=s)
plt.show()
gives
Notice how the size increases very quickly. If instead we have
# doubling the area of markers
x = [0,2,4,6,8,10]
y ...
What's the idiomatic syntax for prepending to a short python list?
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The s.insert(0, x) form is the most common.
Whenever you see it though, it may be time to consider using a collections.deque instead of a list.
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Where can I find a NuGet package for upgrading to System.Web.Http v5.0.0.0?
Just upgraded an ASP.NET MVC4 project to use Unity.WebApi version 5.0.0.0 and it requires System.Web.Http v 5.0.0.0 as per the following error:
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Detect if Visual C++ Redistributable for Visual Studio 2012 is installed
How to detect if Visual C++ Redistributable for Visual Studio 2012 is installed?
20 Answers
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Replace all elements of Python NumPy Array that are greater than some value
...o replace all values in it greater than or equal to a threshold T with 255.0. To my knowledge, the most fundamental way would be:
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