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What is the syntax rule for having trailing commas in tuple definitions?
...hen you won't add another line to the end expecting to add another element and instead just creating a valid expression:
a = [
"a",
"b"
"c"
]
Assuming that started as a 2 element list that was later extended it has gone wrong in a perhaps not immediately obvious way. Always include the t...
How can I profile Python code line-by-line?
I've been using cProfile to profile my code, and it's been working great. I also use gprof2dot.py to visualize the results (makes it a little clearer).
...
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...
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.
...
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 ...
How do I generate random numbers in Dart?
How do I generate random numbers using Dart?
13 Answers
13
...
Is there a difference between “raise exception()” and “raise exception” without parenthesis?
...
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...
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.
...
Upgrade python packages from requirements.txt using pip command
... I upgrade all my python packages from requirements.txt file using pip command?
13 Answers
...
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...