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Delete the first three rows of a dataframe in pandas
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edited Oct 17 '18 at 1:06
Acumenus
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answered...
The difference between the Runnable and Callable interfaces in Java
What is the difference between using the Runnable and Callable interfaces when designing a concurrent thread in Java, why would you choose one over the other?
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getMinutes() 0-9 - How to display two digit numbers?
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20 Answers
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Active
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How to run cron job every 2 hours
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Just do:
0 */2 * * * /home/username/test.sh
The 0 at the beginning means to run at the 0th minute. (If it were an *, the script would run every minute during every second hour.)
Don't forget, you can check syslog to see if it eve...
Apply a function to every row of a matrix or a data frame
... 3 4
[3,] 5 6
R> apply(M, 1, function(x) 2*x[1]+x[2])
[1] 4 10 16
R>
This takes a matrix and applies a (silly) function to each row. You pass extra arguments to the function as fourth, fifth, ... arguments to apply().
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SSH library for Java [closed]
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answered Jun 15 '09 at 14:27
David RabinowitzDavid Rabinowitz
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Why does C# disallow readonly local variables?
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It actually has nothing to do with CLI support for the feature, because local variables are in no way exposed to other assemblies. The readonly keyword for fields needs to be supported by the CLI because its effect is visible to oth...
Plot yerr/xerr as shaded region rather than error bars
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from matplotlib import pyplot as plt
import numpy as np
x = np.linspace(0, 30, 30)
y = np.sin(x/6*np.pi)
error = np.random.normal(0.1, 0.02, size=y.shape)
y += np.random.normal(0, 0.1, size=y.shape)
plt.plot(x, y, 'k-')
plt.fill_between(x, y-error, y+error)
plt.show()
See also the matplotlib...
Assert equals between 2 Lists in Junit
...t(actual, is(not(expected)));
}
If you have a recent version of Junit installed with hamcrest, just add these imports:
import static org.junit.Assert.*;
import static org.hamcrest.CoreMatchers.*;
http://junit.org/junit4/javadoc/latest/org/junit/Assert.html#assertThat(T, org.hamcrest.Matcher)
http:...
How can I have two fixed width columns with one flexible column in the center?
...sing width (which is a suggestion when using flexbox), you could use flex: 0 0 230px; which means:
0 = don't grow (shorthand for flex-grow)
0 = don't shrink (shorthand for flex-shrink)
230px = start at 230px (shorthand for flex-basis)
which means: always be 230px.
See fiddle, thanks @TylerH
Oh...