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recursion versus iteration
...where recursion is used a for loop could be used? And if recursion is usually slower what is the technical reason for ever using it over for loop iteration?
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How can I know which radio button is selected via jQuery?
...before needed blah blah ) but for pure performance this works faster especially in older browsers: $("#myform").find("input[type='radio']:checked").val();
– Mark Schultheiss
Aug 3 '15 at 4:45
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Spark java.lang.OutOfMemoryError: Java heap space
... longer need to play with these values, spark will determine them automatically.
Similar to above but shuffle memory fraction. If your job doesn't need much shuffle memory then set it to a lower value (this might cause your shuffles to spill to disk which can have catastrophic impact on speed). So...
Why is the String class declared final in Java?
... have two strings that look alike when "seen as Strings", but that are actually different.
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How to set size for local image using knitr for markdown?
... using this function is that it is portable in the sense that it works for all document formats that knitr supports, so you do not need to think if you have to use, for example, LaTeX or Markdown syntax, to embed an external image. Chunk options related to graphics output that work for normal R plot...
How do I create 7-Zip archives with .NET?
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If you can guarantee the 7-zip app will be installed (and in the path) on all target machines, you can offload by calling the command line app 7z. Not the most elegant solution but it is the least work.
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Is it possible to change only the alpha of a rgba background colour on hover?
...solute on the <div> tag
Option 1: ::before psuedo-element:
.before_method{
position:relative;
}
.before_method:before{
display:block;
content:" ";
position:absolute;
z-index:-1;
background:rgb(18, 176, 41);
top:0;
left:0;
right:0;
bottom:0;
opacity:0.5;
}
.before_metho...
Import CSV to mysql table
...ocalhost';
$user = 'root';
$pass = '';
$database = 'database';
$db = mysql_connect($host, $user, $pass);
mysql_query("use $database", $db);
/********************************************************************************/
// Parameters: filename.csv table_name
$argv = $_SERVER[argv];
if($argv[1...
Getting an “ambiguous redirect” error
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Bash can be pretty obtuse sometimes.
The following commands all return different error messages for basically the same error:
$ echo hello >
bash: syntax error near unexpected token `newline`
$ echo hello > ${NONEXISTENT}
bash: ${NONEXISTENT}: ambiguous redirect
$ echo hello ...
Make $JAVA_HOME easily changable in Ubuntu [closed]
In Ubuntu, I'd like to switch my JAVA_HOME environment variable back and forth between Java 5 and 6.
8 Answers
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