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How does the static modifier affect this code?
...n, 2. Execution
In identification phase all static variables are detected and initialized with default values.
So now the values are:
A obj=null
num1=0
num2=0
The second phase, execution, starts from top to bottom. In Java, the execution starts from the first static members.
Here your first static...
How to select rows from a DataFrame based on column values?
How to select rows from a DataFrame based on values in some column in Pandas?
10 Answers
...
How to get line count of a large file cheaply in Python?
I need to get a line count of a large file (hundreds of thousands of lines) in python. What is the most efficient way both memory- and time-wise?
...
Map Tiling Algorithm
...c idea of this algorithm is to use a pre-processing step to find all edges and then select the correct smoothing tile according to the shape of the edge.
The first step would be to find all edges. In the example below the edge tiles marked with an X are all green tiles with a tan tile as one or mor...
What is an IndexOutOfRangeException / ArgumentOutOfRangeException and how do I fix it?
I have some code and when it executes, it throws a IndexOutOfRangeException , saying,
4 Answers
...
You have already activated rake 0.9.0, but your Gemfile requires rake 0.8.7
... to make sure that rake is mentioned in your Gemfile. If it's not, add it, and specify the version "you already activated".
Then, you'll need to tell bundle to update the rake version it's using for your app:
bundle update rake
It'll update your Gemfile.lock for you.
...
What does numpy.random.seed(0) do?
What does np.random.seed do in the below code from a Scikit-Learn tutorial? I'm not very familiar with NumPy's random state generator stuff, so I'd really appreciate a layman's terms explanation of this.
...
How to validate an email address using a regular expression?
...
The fully RFC 822 compliant regex is inefficient and obscure because of its length. Fortunately, RFC 822 was superseded twice and the current specification for email addresses is RFC 5322. RFC 5322 leads to a regex that can be understood if studied for a few minutes and i...
CSS Font Border?
... a -webkit prefix.
h1 {
-webkit-text-stroke: 2px black; /* width and color */
font-family: sans; color: yellow;
}
<h1>Hello World</h1>
Another possible trick would be to use four shadows, one pixel each on all directions, using property text-shadow:
h1 {
...
What is the smallest possible valid PDF?
...oy. Acrobat opens it, but it complains somewhat. There is one page in it and it is 3/72" square, the minimum allowed by the spec.
However, Acrobat X doesn't even bother with the cross reference table anymore, so we can take that out:
%PDF-1.0
1 0 obj<</Type/Catalog/Pages 2 0 R>>endo...