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proper name for python * operator?
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In Ruby and Perl 6 this has been called "splat", and I think most people from those communities will figure out what you mean if you call it that.
The Python tutorial uses the phrase "unpacking argument lists", which is long and des...
Converting a list to a set changes element order
...at when I am converting a list to set the order of elements is changed and is sorted by character.
11 Answers
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Sankey Diagrams in R?
...jection data
URL <- paste0(
"https://cdn.rawgit.com/christophergandrud/networkD3/",
"master/JSONdata/energy.json")
Energy <- jsonlite::fromJSON(URL)
# Plot
sankeyNetwork(Links = Energy$links, Nodes = Energy$nodes, Source = "source",
Target = "target", Value = "valu...
Why doesn't the example compile, aka how does (co-, contra-, and in-) variance work?
...r. This declaration as a whole means that Function1 is contravariant in P and covariant in R. Thus, we can derive the following axioms:
T1' <: T1
T2 <: T2'
---------------------------------------- S-Fun
Function1[T1, T2] <: Function1[T1', T2']
Notice that T1' must be a subtype (or the ...
Simple way to repeat a String in java
...te this using a for loop, but I wish to avoid for loops whenever necessary and a simple direct method should exist somewhere.
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Is there a difference between “raise exception()” and “raise exception” without parenthesis?
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The short answer is that both raise MyException and raise MyException() do the same thing. This first form auto instantiates your exception.
The relevant section from the docs says, "raise evaluates the first expression as the exception object. It must be either a subcla...
Large, persistent DataFrame in pandas
I am exploring switching to python and pandas as a long-time SAS user.
6 Answers
6
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How to know user has clicked “X” or the “Close” button?
... get it through the sender object. Try to cast sender as a Button control, and verify perhaps for its name "CloseButton", for instance.
private void Form1_FormClosing(object sender, FormClosingEventArgs e) {
if (string.Equals((sender as Button).Name, @"CloseButton"))
// Do something pro...
Setting CSS pseudo-class rules from JavaScript
...0);
document.styleSheets[0].rules[0].style.backgroundColor= 'red';
Older and minor browsers are likely not to support either syntax. Dynamic stylesheet-fiddling is rarely done because it's quite annoying to get right, rarely needed, and historically troublesome.
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Upgrade python packages from requirements.txt using pip command
... I upgrade all my python packages from requirements.txt file using pip command?
13 Answers
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