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Generating a PNG with matplotlib when DISPLAY is undefined
...
Important note: .use needs to be called before pyplot is imported. So if you are, for instance, just trying to import pyplot, you need to import matplotlib first, call use, and than import pyplot.
– seaotternerd
Nov 8 '1...
Which way is best for creating an object in JavaScript? Is `var` necessary before an object property
...your example, Person (you should start the name with a capital letter) is called the constructor function. This is similar to classes in other OO languages.
Use way 2 if you only need one object of a kind (like a singleton). If you want this object to inherit from another one, then you have to use a...
Why is Java Vector (and Stack) class considered obsolete or deprecated?
... each individual operation. That's almost never what you want to do.
Generally you want to synchronize a whole sequence of operations. Synchronizing individual operations is both less safe (if you iterate over a Vector, for instance, you still need to take out a lock to avoid anyone else changing t...
How to compare times in Python?
...use for comparison without taking the date into account:
>>> this_morning = datetime.datetime(2009, 12, 2, 9, 30)
>>> last_night = datetime.datetime(2009, 12, 1, 20, 0)
>>> this_morning.time() < last_night.time()
True
...
Qt 5.1.1: Application failed to start because platform plugin “windows” is missing
...roblem . After a long search I found a comment which had been ignored by all users pointing to the missing lib. Now, many months later, the comment has been changed to an answer. However, when I answered this question by msyself I intended to help other people by directly providing the solution. T...
What is a vertical tab?
..., fill in header, VT to body area, fill in lines, VT to form footer. Generally it was coded in the program as a character constant. From the keyboard, it would be CTRL-K.
I don't believe anyone would have a reason to use it any more. Most forms are generated in a printer control language like po...
What is the purpose of “return await” in C#?
...n async method behave differently: when combined with using (or, more generally, any return await in a try block).
Consider these two versions of a method:
Task<SomeResult> DoSomethingAsync()
{
using (var foo = new Foo())
{
return foo.DoAnotherThingAsync();
}
}
async Tas...
How to disable Golang unused import error
...
Adding an underscore (_) before a package name will ignore the unused import error.
Here is an example of how you could use it:
import (
"log"
"database/sql"
_ "github.com/go-sql-driver/mysql"
)
To import a package solely for i...
How to convert a number to string and vice versa in C++
...o-number conversion and vice-versa are built in into the standard library. All the following functions are present in <string> (as per paragraph 21.5).
string to numeric
float stof(const string& str, size_t *idx = 0);
double stod(const string& str, size_t *id...
Installed Ruby 1.9.3 with RVM but command line doesn't show ruby -v
... what do you do if env has a lot of rvm stuff in it still? like rvm_dump_environment_flag=0 etc...
– jcollum
Apr 22 '12 at 21:28
5
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