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How do I get the row count of a pandas DataFrame?
...erty or just len(DataFrame.index). However, there are notable performance differences ( len(DataFrame.index) is fastest).
Code to reproduce the plot:
import numpy as np
import pandas as pd
import perfplot
perfplot.save(
"out.png",
setup=lambda n: pd.DataFrame(np.arange(n * 3).reshape(n, ...
System.Threading.Timer in C# it seems to be not working. It runs very fast every 3 second
I've a timer object. I want it to be run every minute. Specifically, it should run a OnCallBack method and gets inactive while a OnCallBack method is running. Once a OnCallBack method finishes, it (a OnCallBack ) restarts a timer.
...
Joda-Time: what's the difference between Period, Interval and Duration?
In Joda-Time 2, what is the difference between the three kinds of time spans:
2 Answers
...
I need this baby in a month - send me nine women!
Under what circumstances - if any - does adding programmers to a team actually speed development of an already late project?
...
What is the IntelliJ shortcut key to create a javadoc comment?
In Eclipse, I can press Alt + Shift + J and get a javadoc comment automatically generated with fields, returns, or whatever would be applicable for that specific javadoc comment. I'm assuming that IntelliJ IDEA has this feature. Can anyone tell me if there is a keyboard shortcut for this?
...
How do I draw a shadow under a UIView?
...e(-15, 20), 5);
but before
CGContextRestoreGState(currentContext);
So if you want the superclass's drawRect: to be 'wrapped' in a shadow, then how about if you rearrange your code like this?
- (void)drawRect:(CGRect)rect {
CGContextRef currentContext = UIGraphicsGetCurrentContext();
CG...
Why does Dijkstra's algorithm use decrease-key?
...ends on what priority queue you use. Here's a quick table that shows off different priority queues and the overall runtimes of the different Dijkstra's algorithm implementations:
Queue | T_e | T_d | T_k | w/o Dec-Key | w/Dec-Key
---------------+--------+--------+--------+------...
How to toggle a boolean?
...
@user2846569, if you're toggling the boolean, that means that by nature the variable has already been initialized. You could expand it to bool = !bool || true; to have a default, I suppose.
– Jordan
M...
Array initializing in Scala
...
Additional to Vasil's answer: If you have the values given as a Scala collection, you can write
val list = List(1,2,3,4,5)
val arr = Array[Int](list:_*)
println(arr.mkString)
But usually the toArray method is more handy:
val list = List(1,2,3,4,5)
val...
Circle line-segment collision detection algorithm?
...
(x - h)2 + (y - k)2 = r2
(h,k) = center of circle.
Note: We've simplified the problem to 2D here, the solution we get applies also in 3D
to get:
Expand
x2 - 2xh + h2 + y2 - 2yk + k2 - r2 = 0
Plug
x = ex + tdx
y = ey + tdy
( ex + tdx )2 - 2( ex + tdx )h + h2 +
( ey + tdy )2 - 2( ey + tdy ...