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Remove duplicated rows using dplyr
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@dotcomken Until then could also just use df %>% group_by(x, y) %>% do(head(.,1))
– Holger Brandl
Jul 23 '14 at 11:53
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Maven does not find JUnit tests to run
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91
I also found that the unit test code should put under the test folder, it can not be recognized...
The performance impact of using instanceof in Java
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Modern JVM/JIT compilers have removed the performance hit of most of the traditionally "slow" operations, including instanceof, exception handling, reflection, etc.
As Donald Knuth wrote, "We should forget about small efficiencies, say abou...
How to compare dates in datetime fields in Postgresql?
I have been facing a strange scenario when comparing between dates in postgresql(version 9.2.4 in windows). I have a column in my table say update_date with type 'timestamp without timezone'. Client can search over this field with only date (i.e: 2013-05-03) or date with time (i.e: 2013-05-03 12:20:...
HTML5 Audio stop function
...ocument.getElementById('radio-link');
var src = "http://192.81.248.91:8159/;";
switch(state) {
case 0:
player.src = src;
player.load();
player.play();
link.innerHTML = 'Pa...
Can I specify multiple users for myself in .gitconfig?
...un
git config user.name "Your Name Here"
git config user.email your@email.com
whereas the default user / email is configured in your ~/.gitconfig
git config --global user.name "Your Name Here"
git config --global user.email your@email.com
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showDialog deprecated. What's the alternative?
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From http://developer.android.com/reference/android/app/Activity.html
public final void showDialog (int id) Added in API level 1
This method was deprecated in API level 13. Use the new DialogFragment
class with FragmentManager instead; this is ...
Environment variables for java installation
...plaining the rationale behind all these environment variables.
Optional recommendations
Add an user environment variable JAVA_TOOL_OPTIONS with value -Dfile.encoding="UTF-8". This ensures that Java (and tools such as Maven) will run with a Charset.defaultCharset() of UTF-8 (instead of the default...
Callback of .animate() gets called twice jquery
...n the set you call animate on:
If supplied, the start, step, progress, complete, done, fail, and always callbacks are called on a per-element basis...
Since you're animating two elements (the html element, and the body element), you're getting two callbacks. (For anyone wondering why the OP is...