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How can a Java variable be different from itself?
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One simple way is to use Float.NaN:
float x = Float.NaN; // <--
if (x == x) {
System.out.println("Ok");
} else {
System.out.println("Not ok");
}
Not ok
You can do the same with Double.NaN.
From JLS §15.21.1. Numerical Equality Operators == and !=:
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Increase number of axis ticks
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You can override ggplots default scales by modifying scale_x_continuous and/or scale_y_continuous. For example:
library(ggplot2)
dat <- data.frame(x = rnorm(100), y = rnorm(100))
ggplot(dat, aes(x,y)) +
geom_point()
Gives you this:
And overriding the scales can give you s...
Which is better option to use for dividing an integer number by 2?
... treating it as a numerical value, use division.
Note that they are not exactly equivalent. They can give different results for negative integers. For example:
-5 / 2 = -2
-5 >> 1 = -3
(ideone)
share
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Batch script loop
I need to execute a command 100-200 times, and so far my research indicates that I would either have to copy/paste 100 copies of this command, OR use a for loop, but the for loop expects a list of items, hence I would need 200 files to operate on, or a list of 200 items, defeating the point.
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What's the difference between lists enclosed by square brackets and parentheses in Python?
...es.
A list is mutable, meaning you can change its contents:
>>> x = [1,2]
>>> x.append(3)
>>> x
[1, 2, 3]
while tuples are not:
>>> x = (1,2)
>>> x
(1, 2)
>>> x.append(3)
Traceback (most recent call last):
File "<stdin>", line 1, in ...
Set value for particular cell in pandas DataFrame using index
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RukTech's answer, df.set_value('C', 'x', 10), is far and away faster than the options I've suggested below. However, it has been slated for deprecation.
Going forward, the recommended method is .iat/.at.
Why df.xs('C')['x']=10 does not work:
df.xs('C') by d...
Pass a data.frame column name to a function
I'm trying to write a function to accept a data.frame ( x ) and a column from it. The function performs some calculations on x and later returns another data.frame. I'm stuck on the best-practices method to pass the column name to the function.
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What is the difference between currying and partial application?
I quite often see on the Internet various complaints that other peoples examples of currying are not currying, but are actually just partial application.
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Making WPF applications look Metro-styled, even in Windows 7? (Window Chrome / Theming / Theme)
...le. Because I like to have control over everything and I didn't want some external libraries just to use a Window from it. I looked at already mentioned MahApps.Metro on GitHub
and also very nice Modern UI on GitHub. (.NET4.5 only)
There is one more it's Elysium but I really didn't try this on...
How to make a valid Windows filename from an arbitrary string?
...lidFileNameChars = new char[] { '"', '<', '>', '|', '\0', '\x0001', '\x0002', '\x0003', '\x0004', '\x0005', '\x0006', '\a', '\b', '\t', '\n', '\v', '\f', '\r', '\x000e', '\x000f', '\x0010', '\x0011', '\x0012', '\x0013', '\x0014', '\x0015', '\x0016', '\x0017', '\x0018', '\x001...