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How to combine multiple conditions to subset a data-frame using “OR”?
... it is to be handled as I intended, since ...
> NA & 1
[1] NA
> 0 & NA
[1] FALSE
Order of arguments may matter when using '&".
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How do you find the sum of all the numbers in an array in Java?
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In java-8 you can use streams:
int[] a = {10,20,30,40,50};
int sum = IntStream.of(a).sum();
System.out.println("The sum is " + sum);
Output:
The sum is 150.
It's in the package java.util.stream
import java.util.stream.*;
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Assign multiple columns using := in data.table, by group
... a b col1 col2 mean sum Name1 Longer%
# 1: 1 1 hi hello 2.5 5 10 15
# 2: 2 2 hi hello 3.5 7 14 21
# 3: 3 3 hi hello 4.5 9 18 27
# 4: 1 4 hi hello 2.5 5 10 15
# 5: 2 5 hi hello 3.5 7 14 21
# 6: 3 6 hi hello 4.5 9 18 27
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Changing font size and direction of axes text in ggplot2
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301
Use theme():
d <- data.frame(x=gl(10, 1, 10, labels=paste("long text label ", letters[1:10]...
Saving a Numpy array as an image
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answered May 24 '09 at 0:26
dF.dF.
64.2k2727 gold badges123123 silver badges134134 bronze badges
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How to get a DOM Element from a JQuery Selector
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You can access the raw DOM element with:
$("table").get(0);
or more simply:
$("table")[0];
There isn't actually a lot you need this for however (in my experience). Take your checkbox example:
$(":checkbox").click(function() {
if ($(this).is(":checked")) {
// do stuff
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'float' vs. 'double' precision
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edited Dec 30 '14 at 20:59
answered Feb 23 '11 at 23:24
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Drawable image on a canvas
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edited Dec 15 '18 at 12:07
answered Apr 8 '14 at 8:36
Gá...
How to count duplicate value in an array in javascript
...];
array_elements.sort();
var current = null;
var cnt = 0;
for (var i = 0; i < array_elements.length; i++) {
if (array_elements[i] != current) {
if (cnt > 0) {
document.write(current + ' comes --> ' + cnt + ' times<br>');
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