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Using jquery to get element's position relative to viewport
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edited Apr 17 '13 at 9:50
Pang
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answered Oc...
Check whether number is even or odd
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204
You can use the modulus operator, but that can be slow. If it's an integer, you can do:
if ( (...
Test whether string is a valid integer
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[[ $var =~ ^-?[0-9]+$ ]]
The ^ indicates the beginning of the input pattern
The - is a literal "-"
The ? means "0 or 1 of the preceding (-)"
The + means "1 or more of the preceding ([0-9])"
The $ indicates the end of the input pattern
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Relative frequencies / proportions with dplyr
...n = n()) %>%
mutate(freq = n / sum(n))
# am gear n freq
# 1 0 3 15 0.7894737
# 2 0 4 4 0.2105263
# 3 1 4 8 0.6153846
# 4 1 5 5 0.3846154
From the dplyr vignette:
When you group by multiple variables, each summary peels off one level of the grouping. That makes ...
How to create an array containing 1…N
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409
If I get what you are after, you want an array of numbers 1..n that you can later loop through....
How do I get the real .height() of a overflow: hidden or overflow: scroll div?
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Use the .scrollHeight property of the DOM node: $('#your_div')[0].scrollHeight
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Ruby: Merging variables in to a string
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answered Feb 16 '09 at 21:42
Mike WoodhouseMike Woodhouse
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What does value & 0xff do in Java?
... = value;
then result would end up with the value ff ff ff fe instead of 00 00 00 fe. A further subtlety is that the & is defined to operate only on int values1, so what happens is:
value is promoted to an int (ff ff ff fe).
0xff is an int literal (00 00 00 ff).
The & is applied to yield...
Finding the max value of an attribute in an array of objects
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808
To find the maximum y value of the objects in array:
Math.max.apply(Math, array.map(function(o...
Format output string, right alignment
...r.format syntax:
line_new = '{:>12} {:>12} {:>12}'.format(word[0], word[1], word[2])
And here's how to do it using the old % syntax (useful for older versions of Python that don't support str.format):
line_new = '%12s %12s %12s' % (word[0], word[1], word[2])
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