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How to implement a binary tree?
...ice implementation. I'm just here to point out some style stuff. python usually does node is not None instead of your (node!=None). Also, you can use the __str__ function instead of the printTree method.
– Jeff Mandell
Oct 18 '15 at 2:30
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Principal component analysis in Python
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Months later, here's a small class PCA, and a picture:
#!/usr/bin/env python
""" a small class for Principal Component Analysis
Usage:
p = PCA( A, fraction=0.90 )
In:
A: an array of e.g. 1000 observations x 20 variables, 1000 rows x 20 colum...
List attributes of an object
...ict__
Then you can test what type is with type() or if is a method with callable().
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Why does the C preprocessor interpret the word “linux” as the constant “1”?
Why does the C preprocessor in GCC interpret the word linux (small letters) as the constant 1 ?
5 Answers
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What's the point of Spring MVC's DelegatingFilterProxy?
...ent. The positions of the standard filters are fixed (see the filter order table in the >namespace introduction), removing a common source of errors with previous versions of the framework >when users had to configure the filter chain explicitly in theFilterChainProxy bean. You can, of >cou...
How to include PHP files that require an absolute path?
... just a question, why realpath() for $_SERVER["DOCUMENT_ROOT"]? This shall not output always the canonical path?
– João Pimentel Ferreira
Nov 15 '15 at 0:30
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How to make an immutable object in Python?
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Can you use namedtuple internally inside the class instead of instantiating the object externally? I'm very new to python but the advantage to your other answer is that I can have a class hide the details and also have the power of things like optional p...
R - Markdown avoiding package loading messages
...clude=FALSE,}
knitr::opts_chunk$set(echo = TRUE, warning=FALSE)
#formating tables
library(xtable)
#data wrangling
library(dplyr)
#text processing
library(stringi)
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Does MongoDB's $in clause guarantee order
...d index order as shown.
If you need to preserve this order, then you basically have two options.
So let's say that you were matching on the values of _id in your documents with an array that is going to be passed in to the $in as [ 4, 2, 8 ].
Approach using Aggregate
var list = [ 4, 2, 8 ];
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Is there a Max function in SQL Server that takes two values like Math.Max in .NET?
...next guy.
You can find multiple aggregates using SQL Server 2008's derived_tables like so: SELECT MAX(a), MAX(b) FROM (VALUES (1, 2), (3, 4), (5, 6), (7, 8), (9, 10) ) AS MyTable(a, b)
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