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Object reference not set to an instance of an object.Why doesn't .NET show which object is `null`?
...ull
IL_0002: stloc.0 // s
IL_0003: ldloc.0 // s
IL_0004: callvirt System.String.get_Length
IL_0009: call System.Console.WriteLine
It is the callvirt opcode that throws the NullReferenceException and it does that when the first argument on the evaluation stack is a null ...
Input and output numpy arrays to h5py
I have a Python code whose output is a sized matrix, whose entries are all of the type float . If I save it with the extension .dat the file size is of the order of 500 MB. I read that using h5py reduces the file size considerably. So, let's say I have the 2D numpy array named A . How do I ...
How can I get dictionary key as variable directly in Python (not by searching from value)?
...f you want to print key and value, use the following:
for key, value in my_dict.iteritems():
print key, value
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Why should I prefer to use member initialization lists?
...tyle. For class members which are classes, then it avoids an unnecessary call to a default constructor. Consider:
class A
{
public:
A() { x = 0; }
A(int x_) { x = x_; }
int x;
};
class B
{
public:
B()
{
a.x = 3;
}
private:
A a;
};
In this case, the construct...
Git push rejected after feature branch rebase
...hat remote branch can be fast-forwarded to your local branch, that is that all the difference between local and remote branches is in local having some new commits at the end like that:
Z--X--R <- origin/some-branch (can be fast-forwarded to Y commit)
\
T--Y <...
Session variables in ASP.NET MVC
I am writing a web application that will allow a user to browse to multiple web pages within the website making certain requests. All information that the user inputs will be stored in an object that I created. The problem is that I need this object to be accessed from any part of the website and I ...
Rails: confused about syntax for passing locals to partials
...:partial => 'foo', :locals => {blah blah blah}) then it will pass in all of your arguments as a hash and parse them accordingly.
If you pass in a string as your first argument, it assumes the first argument is your partial name, and will pass the remainder as your locals. However, in that s...
Arduino Sketch upload issue - avrdude: stk500_recv(): programmer is not responding
...it works. I figured the packets were some attempt at a hand-shake. So basically, I solved it using Google, patience and futzing around with the board!
– hoipolloi
Jan 12 '14 at 18:16
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Converting integer to string in Python
... string is done with the builtin str() function, which basically calls the __str__() method of its parameter.
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get list from pandas dataframe column
...rame columns are Pandas Series when you pull them out, which you can then call x.tolist() on to turn them into a Python list. Alternatively you cast it with list(x).
import pandas as pd
data_dict = {'one': pd.Series([1, 2, 3], index=['a', 'b', 'c']),
'two': pd.Series([1, 2, 3, 4], inde...