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Example use of “continue” statement in Python?
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Here's a simple example:
for letter in 'Django':
if letter == 'D':
continue
print("Current Letter: " + letter)
Output will be:
Current Letter: j
Current Letter: a
Current Letter: n
Current Letter: g
Current Letter: o
It ...
How do Trigonometric functions work?
...roblems they solve. But they have always been presented to me as a black box. If you need the Sine or Cosine of something, you hit the sin or cos button on your calculator and you're set. Which is fine.
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Clear icon inside input text
Is there a quick way to create an input text element with an icon on the right to clear the input element itself (like the google search box)?
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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 a...
Difference between Inheritance and Composition
...aving an instance of another class C as a field of your class, instead of extending C. A good example where composition would've been a lot better than inheritance is java.util.Stack, which currently extends java.util.Vector. This is now considered a blunder. A stack "is-NOT-a" vector; you should no...
do { … } while (0) — what is it good for? [duplicate]
I've been seeing that expression for over 10 years now. I've been trying to think what it's good for. Since I see it mostly in #defines, I assume it's good for inner scope variable declaration and for using breaks (instead of gotos.)
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Hidden Features of JavaScript? [closed]
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Side-by-side plots with ggplot2
...de-by-side (or n plots on a grid)
The function grid.arrange() in the gridExtra package will combine multiple plots; this is how you put two side by side.
require(gridExtra)
plot1 <- qplot(1)
plot2 <- qplot(1)
grid.arrange(plot1, plot2, ncol=2)
This is useful when the two plots are not bas...
How to convert JSON data into a Python object
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# Parse JSON into an object with attributes corresponding to dict keys.
x = json.loads(data, object_hook=lambda d: SimpleNamespace(**d))
print(x.name, x.hometown.name, x.hometown.id)
OLD ANSWER (Python2)
In Python2, you can do it in one line, using namedtuple and object_hook (but it's very slow ...
How can I count the occurrences of a list item?
...you want to count all items, or even just multiple items, use Counter, as explained in the other answers.
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