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How to count TRUE values in a logical vector
...m(z) # gives you NA
table(z)["TRUE"] # gives you 1
length(z[z == TRUE]) # f3lix answer, gives you 2 (because NA indexing returns values)
So I think the safest is to use na.rm = TRUE:
sum(z, na.rm = TRUE) # best way to count TRUE values
(which gives 1). I think that table solution is less effici...
Using CSS how to change only the 2nd column of a table
...raver
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How to parse a JSON string into JsonNode in Jackson?
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377
A slight variation on Richards answer but readTree can take a string so you can simplify it to...
How do I install package.json dependencies in the current directory using npm
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Gray out image with CSS?
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Does it have to be gray? You could just set the opacity of the image lower (to dull it). Altern...
Using Python String Formatting with Lists
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edited Sep 27 '11 at 12:03
answered Sep 27 '11 at 11:53
in...
Insert new item in array on any position in PHP
...); // not necessarily an array, see manual quote
array_splice( $original, 3, 0, $inserted ); // splice in at position 3
// $original is now a b c x d e
If replacement is just one element it is not necessary to put array() around it, unless the element is an array itself, an object or NULL.
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Object.getOwnPropertyNames vs Object.keys
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Code for a simple JavaScript countdown timer?
I want to use a simple countdown timer starting at 30 seconds from when the function is run and ending at 0. No milliseconds. How can it be coded?
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UILabel - Wordwrap text
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If you set numberOfLines to 0 (and the label to word wrap), the label will automatically wrap ...