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How to combine multiple conditions to subset a data-frame using “OR”?
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my.data.frame <- subset(data , V1 > 2 | V2 < 4)
An alternative solution that mimics the behavior of this function and would be more appropriate for inclusion within a function body:
new.data <- data[ which( data$V1 > 2 | data$V2 < 4) , ]
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How do I check if a string is a number (float)?
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Retina displays, high-res background images
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Do I need to double the size of the .box div to 400px by 400px to
match the new high res ...
“tag already exists in the remote" error after recreating the git tag
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Edit, 24 Nov 2016: this answer is apparently popular, so I am adding a note here. If you repl...
How to detect page zoom level in all modern browsers?
... this page to test all these methods of measuring the zoom level.
Edit (2011-12-12): I've added a project that can be cloned: https://github.com/tombigel/detect-zoom
IE8: screen.deviceXDPI / screen.logicalXDPI (or, for the zoom level relative to default zoom, screen.systemXDPI / screen.logicalXDP...
How to split a file into equal parts, without breaking individual lines? [duplicate]
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145
If you mean an equal number of lines, split has an option for this:
split --lines=75
If you...
Get distance between two points in canvas
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211
You can do it with pythagoras theorem
If you have two points (x1, y1) and (x2, y2)
then you ca...
How do you round a number to two decimal places in C#?
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15 Answers
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Calculating arithmetic mean (one type of average) in Python
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12 Answers
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