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What is the performance cost of having a virtual method in a C++ class?
...any of its parent classes) means that the class will have a virtual table, and every instance will have a virtual pointer.
...
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', ...
Why are floating point numbers inaccurate?
...t numbers are represented a lot like scientific notation: with an exponent and a mantissa (also called the significand). A very simple number, say 9.2, is actually this fraction:
5179139571476070 * 2 -49
Where the exponent is -49 and the mantissa is 5179139571476070. The reason it is impossibl...
ValueError: numpy.dtype has the wrong size, try recompiling
I just installed pandas and statsmodels package on my python 2.7
When I tried "import pandas as pd", this error message comes out.
Can anyone help? Thanks!!!
...
What is the JSF resource library for and how should it be used?
The JSF <h:outputStylesheet> , <h:outputScript> and <h:graphicImage> components have a library attribute. What is this and how should this be used? There are a lot of examples on the web which use it as follows with the common content/file type css , js and img (or ima...
What, exactly, is needed for “margin: 0 auto;” to work?
...lement is used to centre it (left-right). However, I know that the element and its parent must meet certain criteria for the auto margin to work, and I can never seem to get the magic right.
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UILabel text margin [duplicate]
I'm looking to set the left inset/margin of a UILabel and can't find a method to do so. The label has a background set so just changing its origin won't do the trick. It would be ideal to inset the text by 10px or so on the left hand side.
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OS X Terminal Colors [closed]
...rminal colors.
Edit your .bash_profile (since OS X 10.8) — or (for 10.7 and earlier): .profile or .bashrc or /etc/profile (depending on availability) — in your home directory and add following code:
export CLICOLOR=1
export LSCOLORS=GxFxCxDxBxegedabagaced
CLICOLOR=1 simply enables coloring o...
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...
How to install GCC piece by piece with GMP, MPFR, MPC, ELF, without shared libraries?
...s of dependencies, not using a package manager (like yum, rpm, apt, dpkg), and not using shared libraries?
6 Answers
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