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What's the difference between lapply and do.call?
I'm learning R recently and confused by two function: lapply and do.call . It seems that they're just similar to map function in Lisp. But why are there two functions with such a different name? Why doesn't R just use a function called map ?
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How do I invoke a Java method when given the method name as a string?
... edited Sep 29 '16 at 14:13
Andrew Tobilko
42.5k1111 gold badges6666 silver badges119119 bronze badges
answered Oct 2 '08 at 5:30
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Is it possible to set the stacking order of pseudo-elements below their parent element? [duplicate]
...ange the default stacking order.
Positioning the pseudo-element (absolute) and assigning a z-index value other than “auto” creates the new stacking context.
#element {
position: relative; /* optional */
width: 100px;
height: 100px;
background-color: blue;
}
#elemen...
What are the aspect ratios for all Android phone and tablet devices?
I'm looking for a list of all screen aspect ratios for popular Android based Phones and Tablets.
5 Answers
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Spark java.lang.OutOfMemoryError: Java heap space
... suggestions:
If your nodes are configured to have 6g maximum for Spark (and are leaving a little for other processes), then use 6g rather than 4g, spark.executor.memory=6g. Make sure you're using as much memory as possible by checking the UI (it will say how much mem you're using)
Try using more ...
What does CultureInfo.InvariantCulture mean?
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Not all cultures use the same format for dates and decimal / currency values.
This will matter for you when you are converting input values (read) that are stored as strings to DateTime, float, double or decimal. It will also matter if you try to format the aforementio...
Select row with most recent date per user
I have a table ("lms_attendance") of users' check-in and out times that looks like this:
11 Answers
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Dynamic variable names in Bash
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Use an associative array, with command names as keys.
# Requires bash 4, though
declare -A magic_variable=()
function grep_search() {
magic_variable[$1]=$( ls | tail -1 )
echo ${magic_variable[$1]}
}
If you can't use associative arrays (e.g., you m...
Git diff to show only lines that have been modified
... edited Sep 2 '15 at 17:24
Andrzej Rehmann
7,71366 gold badges3030 silver badges3535 bronze badges
answered Sep 15 '13 at 9:02
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Can someone explain how to implement the jQuery File Upload plugin?
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I was looking for a similar functionality some days back and came across a good tutorial on tutorialzine. Here is an working example. Complete tutorial can be found here.
Simple form to hold the file upload dialogue:
<form id="upload" method="post" action="upload.php" enctype=...