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Complex numbers usage in python [closed]
...math newbie. Now I'm getting deeper into Python data types. I can't understand how to use a complex number. Please give me examples of usage of complex numbers in Python.
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What are the rules for the “…” token in the context of variadic templates?
...tion passing T as {int, char, short}, then each of the function call is expanded as:
g( arg0, arg1, arg2 );
h( x(arg0), x(arg1), x(arg2) );
m( y(arg0, arg1, arg2) );
n( z<int>(arg0), z<char>(arg1), z<short>(arg2) );
In the code you posted, std::forward follows the fourt...
Mocha / Chai expect.to.throw not catching thrown errors
...test keeps failing on the thrown error, but If I wrap the test case in try and catch and assert on the caught error, it works.
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How to manually create icns files using iconutil?
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Use iconutil to Create an icns File Manually
The iconutil command-line tool converts iconset folders to deployment-ready, high-resolution icns files. (You can find complete documentation for this tool by entering man iconutil in Terminal.) Using this tool also compresses the resulting i...
How to detect if a function is called as constructor?
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NOTE: This is now possible in ES2015 and later. See Daniel Weiner's answer.
I don't think what you want is possible [prior to ES2015]. There simply isn't enough information available within the function to make a reliable inference.
Looking at the ECMAScript 3...
Omit rows containing specific column of NA
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You could use the complete.cases function and put it into a function thusly:
DF <- data.frame(x = c(1, 2, 3), y = c(0, 10, NA), z=c(NA, 33, 22))
completeFun <- function(data, desiredCols) {
completeVec <- complete.cases(data[, desiredCols])
return(data...
What's the difference between lists enclosed by square brackets and parentheses in Python?
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for the above 'y=x' example , list and tuple behave in the same way now (verified in python3.8.5)
– Youjun Hu
Aug 15 at 9:11
add a comm...
Hidden Features of JavaScript? [closed]
...ay -- it's just an object. So you can't do join(), pop(), push(), slice() and so forth. (You can convert it to a real array if you want: "var argArray = Array.prototype.slice.call(arguments);" )
– Jacob Mattison
Jan 26 '09 at 21:37
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Remove duplicated rows using dplyr
...mple(0:1, 10, replace = T),
z = 1:10
)
One approach would be to group, and then only keep the first row:
df %>% group_by(x, y) %>% filter(row_number(z) == 1)
## Source: local data frame [3 x 3]
## Groups: x, y
##
## x y z
## 1 0 1 1
## 2 1 0 2
## 3 1 1 4
(In dplyr 0.2 you won't need...
What is Scala's yield?
I understand Ruby and Python's yield. What does Scala's yield do?
9 Answers
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