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data.table vs dplyr: can one do something well the other can't or does poorly?
..., keyby = .(x,y)][DT2][, z := z*mul][]
# dplyr equivalent
DF1 %>% group_by(x, y) %>% summarise(z = sum(z)) %>%
right_join(DF2) %>% mutate(z = z * mul)
2) do it all in one go (using by = .EACHI feature):
DT1[DT2, list(z=sum(z) * mul), by = .EACHI]
What is the advantage?
We do...
HTML5 Canvas 100% Width Height of Viewport?
...es the text. You unfortunately have to use JS.
– i336_
May 10 '16 at 1:56
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How can I know when an EditText loses focus?
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Kotlin way
editText.setOnFocusChangeListener { _, hasFocus ->
if (!hasFocus) { }
}
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Why does Iterable not provide stream() and parallelStream() methods?
...reamSupport.stream(iter.spliterator(), false);
– user_3380739
Dec 2 '16 at 22:56
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How to navigate through textfields (Next / Done Buttons)
...ssumptions can be ignored as well.
Swift 4.0
func textFieldShouldReturn(_ textField: UITextField) -> Bool {
let nextTag = textField.tag + 1
// Try to find next responder
let nextResponder = textField.superview?.viewWithTag(nextTag) as UIResponder!
if nextResponder != nil {
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How to find all positions of the maximum value in a list?
...t was a little tricky figuring out the proper initialization values for max_val and max_indices which worked for all possible cases, especially if the max happened to be the first value in the list — but I believe it now does.
def maxelements(seq):
''' Return list of position(s) of largest el...
Should developers have administrator permissions on their PC
...scrubbed clean, but we know this is not the case.
– L_7337
Sep 13 '18 at 15:24
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delete map[key] in go?
...sions = map[string] chan int{};
sessions["moo"] = make (chan int);
_, ok := sessions["moo"];
if ok {
delete(sessions, "moo");
}
}
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Change x axes scale in matplotlib
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Try using matplotlib.pyplot.ticklabel_format:
import matplotlib.pyplot as plt
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plt.ticklabel_format(style='sci', axis='x', scilimits=(0,0))
This applies scientific notation (i.e. a x 10^b) to your x-axis tickmarks
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In HTML I can make a checkmark with ✓ . Is there a corresponding X-mark?
... Not the comprehensive list, but a start at w3schools.com/tags/ref_symbols.asp
– Bill the Lizard
Apr 3 '09 at 0:44
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