大约有 15,461 项符合查询结果（耗时：0.0351秒） [XML]
Check if an apt-get package is installed and then install it if it's not on Linux
...ok config-files or similar, so it's "ok" - so to me, this is not a safe test. dpkg-query -l doesnt seem to return a useful result in this case either.
– keen
Sep 23 '16 at 19:49
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What integer hash function are good that accepts an integer hash key?
...turn x;
}
The magic number was calculated using a special multi-threaded test program that ran for many hours, which calculates the avalanche effect (the number of output bits that change if a single input bit is changed; should be nearly 16 on average), independence of output bit changes (output ...
Ignore mouse interaction on overlay image
... Yup -- This is the good stuff. It also works in suppressing hit-testing for elements with no backgrounds set that are being used as containers for other items (that you actually do want to hit-test.)
– Armentage
Feb 8 '12 at 5:22
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Where can I learn how to write C code to speed up slow R functions? [closed]
...as hundreds of packages, some from authors you trust. That provides real, tested examples to study and adapt.
But as Josh suspected, I lean more towards C++ and hence Rcpp. It also has plenty of examples.
Edit: There were two books I found helpful:
The first one is Venables and Ripley's "S Prog...
com.jcraft.jsch.JSchException: UnknownHostKey
...HostKeyChecking" (this introduces insecurities and should only be used for testing purposes), using the following code:
java.util.Properties config = new java.util.Properties();
config.put("StrictHostKeyChecking", "no");
session.setConfig(config);
Option #1 (adding the host to the ~/.ssh/known_...
How can I reverse a list in Python?
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When I tested this slicing was about twice as fast (when reversing a 10k elements list and creating a list from it). I did not test memory consumption though. reverse might be faster though, if you don't need to cast to list afterwa...
Media Player called in state 0, error (-38,0)
...
This is my code,tested and working fine:
package com.example.com.mak.mediaplayer;
import android.media.MediaPlayer;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import android.app.Activity;
public clas...
How to check if a float value is a whole number
...l round to 16 digits; 1.0000000000000001 is displayed as 1.0, in 3 the shortest string representation that produces the same value is shown.
– Martijn Pieters♦
Feb 5 '14 at 17:21
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What is the most pythonic way to check if an object is a number?
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Use Number from the numbers module to test isinstance(n, Number) (available since 2.6).
>>> from numbers import Number
... from decimal import Decimal
... from fractions import Fraction
... for n in [2, 2.0, Decimal('2.0'), complex(2, 0), Fraction(2, 1)...
“The given path's format is not supported.”
...e properties security tab.
var yourJson = System.IO.File.ReadAllText(@"D:\test\json.txt"); // Works
var yourJson = System.IO.File.ReadAllText(@"D:\test\json.txt"); // Error
So those, identical at first glance, two lines are actually different.
...