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Test if a command outputs an empty string
...r success, non-zero for failure). For example:
files=$(ls -A)
if [[ $? != 0 ]]; then
echo "Command failed."
elif [[ $files ]]; then
echo "Files found."
else
echo "No files found."
fi
More info here.
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httpd: Could not reliably determine the server's fully qualified domain name, using 127.0.0.1 for Se
I tried to restart my Apache server on CentOS 5.0 and got this message:
11 Answers
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How to get first element in a list of tuples?
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>>> a = [(1, u'abc'), (2, u'def')]
>>> [i[0] for i in a]
[1, 2]
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dropping infinite values from dataframes in pandas?
...nf, -np.inf])
In [12]: df.replace([np.inf, -np.inf], np.nan)
Out[12]:
0
0 1
1 2
2 NaN
3 NaN
The same method would work for a Series.
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Can you use CSS to mirror/flip text?
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edited Jun 4 '19 at 17:30
Hernán Eche
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Gradients on UIView and UILabels On iPhone [duplicate]
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answered Jan 8 '09 at 0:59
Kendall Helmstetter GelnerKendall Helmstetter Gelner
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In Ruby how do I generate a long string of repeated text?
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310
str = "0" * 999999
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How can I update the current line in a C# Windows Console App?
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805
If you print only "\r" to the console the cursor goes back to the beginning of the current line...
How to initialise memory with new operator in C++?
...ay of type int with the new operator, how can I initialise them all to 0 without looping through them all myself? Should I just use memset ? Is there a “C++” way to do it?
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Javascript seconds to minutes and seconds
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To get the number of full minutes, divide the number of total seconds by 60 (60 seconds/minute):
var minutes = Math.floor(time / 60);
And to get the remaining seconds, multiply the full minutes with 60 and subtract from the total seconds:
var seconds = time - minutes * 60;
Now if you also wan...