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How do I calculate a point on a circle’s circumference?
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The parametric equation for a circle is
x = cx + r * cos(a)
y = cy + r * sin(a)
Where r is the radius, cx,cy the origin, and a the angle.
That's pretty easy to adapt into any language with basic trig functions. Note that most languages will use radians for the angle in trig functio...
Does Python have a ternary conditional operator?
If Python does not have a ternary conditional operator, is it possible to simulate one using other language constructs?
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What does the construct x = x || y mean?
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It means the title argument is optional. So if you call the method with no arguments it will use a default value of "Error".
It's shorthand for writing:
if (!title) {
title = "Error";
}
This kind of shorthand trick with boolean expressions is common in Perl too. Wit...
Convert one date format into another in PHP
Is there a simple way to convert one date format into another date format in PHP?
15 Answers
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How do I initialize the base (super) class?
In Python, consider I have the following code:
4 Answers
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How can I get the intersection, union, and subset of arrays in Ruby?
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Utilizing the fact that you can do set operations on arrays by doing &(intersection), -(difference), and |(union).
Obviously I didn't implement the MultiSet to spec, but this should get you started:
class MultiSet
attr_accessor :set
def in...
How do I plot in real-time in a while loop using matplotlib?
I am trying to plot some data from a camera in real time using OpenCV. However, the real-time plotting (using matplotlib) doesn't seem to be working.
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Calculating Pearson correlation and significance in Python
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You can have a look at scipy.stats:
from pydoc import help
from scipy.stats.stats import pearsonr
help(pearsonr)
>>>
Help on function pearsonr in module scipy.stats.stats:
pearsonr(x, y)
Calculates a Pearson corr...
iOS 7 TableView like in Settings App on iPad
I want to have a group UITableView with the style same like the iPad Settings application Detail view for iOS 7 .
15 Ans...
Get the date (a day before current time) in Bash
How can I print the date which is a day before current time in Bash?
17 Answers
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