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Getting indices of True values in a boolean list
...tions telling me to use enumerate, but I guess I was using it wrong. I was setting the list equal to x, then doing enumerate(x) but I guess all I was doing was enumerating 4? Is that what was happening? Thanks for the help
– Charles Smith
Jan 30 '14 at 22:12
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Selecting data frame rows based on partial string match in a column
...hat the object does not have to be a data.table (but also remember that subsetting approaches for data.frames and data.tables are not identical):
library(data.table)
mtcars[rownames(mtcars) %like% "Merc", ]
iris[iris$Species %like% "osa", ]
If that is what you had, then perhaps you had just mixed...
How to detect if multiple keys are pressed at once using JavaScript?
...t to explain, let's say you press A and B, each fires a keydown event that sets map[e.keyCode] to the value of e.type == keydown, which evaluates to either true or false. Now both map[65] and map[66] are set to true. When you let go of A, the keyup event fires, causing the same logic to determine th...
difference between width auto and width 100 percent
Previously my assumption about width: auto was that the width is set to that of the contents. Now I see that it takes the full width of the parent.
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What are the uses of the exec command in shell scripts? [closed]
...d change the sign-in program in /etc/passwd, but maybe we want environment setting to be used from start-up files. So, in (say) .profile, the last statement says something like:
exec appln-program
so now there is no shell to go back to. Even if appln-program crashes, the end-user cannot get to...
How to instantiate non static inner class within a static method?
...er = new MyClass();
InnerTwo x = outer.new InnerTwo(); // Have to set the hidden pointer
InnerOne y = new InnerOne(); // a "static" inner has no hidden pointer
InnerOne z = new MyClass.InnerOne(); // In other classes you have to spell out the scope
}
}
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Chrome Dev Tools: How to trace network for a link that opens a new tab?
...cent versions (starting with Chrome 50), you can go to the Developer Tools Settings menu (open Developer Tools, then use the 3-dots menu or hit F1) and check the box that says "Auto-open DevTools for popups".
share
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What is the difference between a route and resource in New Router API?
...tween a Route and a Resource . The way I understand Resource helps to set sub paths of a Route object to another Route Object. But its unclear when i think of default name mapping happening for paths as well.
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How to change a git submodule to point to a subfolder?
...t of the boto project . Then, I discovered that I actually need only a subset of this project - specifically, the boto folder.
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How to get the browser viewport dimensions?
... perfect, but it works in my testing on iOs and Android.
//sweet hack to set meta viewport for desktop sites squeezing down to mobile that are big and have a fixed width
//first see if they have window.screen.width avail
(function() {
if (window.screen.width)
{
var setViewport =...