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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, ...
How can you set class attributes from variable arguments (kwargs) in python
...s = {'a', 'b', 'c'}
self.__dict__.update((k, v) for k, v in kwargs.items() if k in allowed_keys)
you could filter the keys beforehand (use iteritems instead of items if you’re still using Python 2.x).
share
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Ruby Array find_first object?
...
use array detect method if you wanted to return first value where block returns true
[1,2,3,11,34].detect(&:even?) #=> 2
OR
[1,2,3,11,34].detect{|i| i.even?} #=> 2
If you wanted to return all values where block returns true then use s...
How to split a string in Java
... this takes a regular expression, so remember to escape special characters if necessary.
there are 12 characters with special meanings: the backslash \, the caret ^, the dollar sign $, the period or dot ., the vertical bar or pipe symbol |, the question mark ?, the asterisk or star *, the plus s...
To Workflow or Not to Workflow?
...
I have done several WF4 projects so lets see if I can add any useful info to the other answers.
From the description of your business problem it sounds like WF4 is a good match, so no problems there.
Regarding your concerns you are right. Basically WF4 is a new produc...
No increment operator (++) in Ruby? [duplicate]
... Regarding point #3, since most things are objects, imagine if Ruby allowed you to do this: 1++ 1+2 # Would not be 3!
– Johntron
Feb 5 '13 at 13:46
...
jQuery Plugin: Adding Callback functionality
...callback in the plugin:
$.fn.myPlugin = function(options, callback) {
if (typeof callback == 'function') { // make sure the callback is a function
callback.call(this); // brings the scope to the callback
}
};
You can also have the callback in the options object:
$.fn.myPlugin = f...
What is the right way to check for a null string in Objective-C?
...ter equality. See Topics for Cocoa: Using Null.
So a good test might be:
if (title == (id)[NSNull null] || title.length == 0 ) title = @"Something";
Note how you can use the fact that even if title is nil, title.length will return 0/nil/false, ie 0 in this case, so you do not have to special cas...
Get a random item from a JavaScript array [duplicate]
...ar randomElement = items[Math.floor(Math.random()*items.length)] if (objResults[randomElement]){ objResults[randomElement]++ }else{ objResults[randomElement] = 1 } } console.log(objResults) The results are pretty randomized af...
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...