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How to test if list element exists?
I would like to test if an element of a list exists, here is an example
7 Answers
7
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Favicon dimensions? [duplicate]
I have a favicon with the dimensions of height=26px / width=20px named favicon.png
10 Answers
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Javascript “Not a Constructor” Exception while creating objects
...ause Project is not a user-defined function / valid constructor.
function x(a,b,c){}
new x(1,2,3); // produces no errors
You've probably done something like this:
function Project(a,b,c) {}
Project = {}; // or possibly Project = new Project
new Project(1,2,3); ...
How can I get this ASP.NET MVC SelectList to work?
...m
{
Selected = (c.CustomerID == invoice.CustomerID),
Text = c.Name,
Value = c.CustomerID.ToString()
};
At second glance I'm not sure I know what you are after...
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Is double square brackets [[ ]] preferable over single square brackets [ ] in Bash?
...ewer surprises and is generally safer to use. But it is not portable - POSIX doesn't specify what it does and only some shells support it (beside bash, I heard ksh supports it too). For example, you can do
[[ -e $b ]]
to test whether a file exists. But with [, you have to quote $b, because it sp...
What is recursion and when should I use it?
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votes
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Show percent % instead of counts in charts of categorical variables
...is was answered there have been some meaningful changes to the ggplot syntax. Summing up the discussion in the comments above:
require(ggplot2)
require(scales)
p <- ggplot(mydataf, aes(x = foo)) +
geom_bar(aes(y = (..count..)/sum(..count..))) +
## version 3.0.0
sc...
How can I make pandas dataframe column headers all lowercase?
...e this:
data.columns = map(str.lower, data.columns)
or
data.columns = [x.lower() for x in data.columns]
example:
>>> data = pd.DataFrame({'A':range(3), 'B':range(3,0,-1), 'C':list('abc')})
>>> data
A B C
0 0 3 a
1 1 2 b
2 2 1 c
>>> data.columns = map(s...
How to get a pixel's x,y coordinate color from an image?
Is there any way to check if a selected(x,y) point of a PNG image is transparent?
4 Answers
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GDB missing in OS X v10.9 (Mavericks)
I went to use GDB in OS X v10.9 (Mavericks), and it's not there. Where has it gone?
12 Answers
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