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A semantics for Bash scripts?
...ripts that appear to work. However, I don't really know what's going on, and I was hoping for a more formal introduction to Bash as a programming language. For example: What is the evaluation order? what are the scoping rules? What is the typing discipline, e.g. is everything a string? What is the...
Multiple queries executed in java in single statement
...c.. Acceptable values for allowMultiQueries property are true, false, yes, and no. Any other value is rejected at runtime with an SQLException.
String dbUrl = "jdbc:mysql:///test?allowMultiQueries=true";
Unless such instruction is passed, an SQLException is thrown.
You have to use execute( S...
Why is reading lines from stdin much slower in C++ than Python?
I wanted to compare reading lines of string input from stdin using Python and C++ and was shocked to see my C++ code run an order of magnitude slower than the equivalent Python code. Since my C++ is rusty and I'm not yet an expert Pythonista, please tell me if I'm doing something wrong or if I'm mis...
What is android:weightSum in android, and how does it work?
I want to know: What is android:weightSum and layout weight, and how do they work?
9 Answers
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How to get different colored lines for different plots in a single figure?
...x)
plt.plot(x, 2 * x)
plt.plot(x, 3 * x)
plt.plot(x, 4 * x)
plt.show()
And, as you may already know, you can easily add a legend:
import matplotlib.pyplot as plt
import numpy as np
x = np.arange(10)
plt.plot(x, x)
plt.plot(x, 2 * x)
plt.plot(x, 3 * x)
plt.plot(x, 4 * x)
plt.legend(['y = x', ...
Selecting pandas column by location
I'm simply trying to access named pandas columns by an integer.
5 Answers
5
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Timeout a command in bash without unnecessary delay
This answer to Command line command to auto-kill a command after a certain amount of time
23 Answers
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What is a “callback” in C and how are they implemented?
From the reading that I have done, Core Audio relies heavily on callbacks (and C++, but that's another story).
9 Answers
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Relatively position an element without it taking up space in document flow
How can I relatively position an element, and have it not take up space in the document flow?
6 Answers
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Numbering rows within groups in a data frame
...g this approach, make sure that you are not getting conflicts between plyr and dplyr as explained in this post It can be avoided by explicitly calling dplyr::mutate(...)
– EcologyTom
Apr 10 '18 at 14:16
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