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How to determine if a point is in a 2D triangle? [closed]
...uction, and division is much, much, slower. Numeric issues are also much smaller, due to no division! all calculations are exact. Thanks, Rick
– user252020
Jan 16 '10 at 4:57
4
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How to succinctly write a formula with many variables from a data frame?
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There is a special identifier that one can use in a formula to mean all the variables, it is the . identifier.
y <- c(1,4,6)
d <- data.frame(y = y, x1 = c(4,-1,3), x2 = c(3,9,8), x3 = c(4,-4,-2))
mod <- lm(y ~ ., data = d)
You can also do things like this, to use all variables but...
How to inherit from a class in javascript?
...t the bottom. I now prefer Object.create(). Object.create is available in all modern browsers.
I should note that Object.create is usually much slower than using new with a function constructor.
//The prototype is just an object when you use `Object.create()`
var Base = {};
//This is how you cre...
How to add an extra column to a NumPy array
...for a way to add a bias unit to my artificial neuronal network in batch on all layers at once, and this is the perfect answer.
– gaborous
Aug 18 '16 at 15:07
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Implement touch using Python?
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On Python2.7: pip install pathlib
– Andre Miras
Oct 24 '17 at 17:54
8
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How to read data when some numbers contain commas as thousand separator?
...u can have read.table or read.csv do this conversion for you semi-automatically. First create a new class definition, then create a conversion function and set it as an "as" method using the setAs function like so:
setClass("num.with.commas")
setAs("character", "num.with.commas",
function(...
Swift: #warning equivalent
...builds clean in production, but I get a warning in development that essentially reminds me I'm in dev mode - using different URLs, timeouts, other settings etc. Arie's suggestion above lets me do this, your technique just flags everything. That said, this technique has its use for sure so I up voted...
When to delete branches in Git?
... uses, if you keep it around. That said, I would delete the branch because all the commits are already there in the history of master, so it does make things much cleaner.
– MatrixFrog
Mar 17 '11 at 3:37
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What does the variable $this mean in PHP?
I see the variable $this in PHP all the time and I have no idea what it's used for. I've never personally used it.
10 An...
Difference between volatile and synchronized in Java
...om obtaining the monitor (or lock) for the same object, thereby preventing all code blocks protected by synchronization on the same object from executing concurrently. Synchronization also creates a "happens-before" memory barrier, causing a memory visibility constraint such that anything done up t...