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How do I get the row count of a pandas DataFrame?
I'm trying to get the number of rows of dataframe df with Pandas, and here is my code.
14 Answers
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Why do we use __init__ in Python classes?
I am having trouble understanding the Initialization of classes.
8 Answers
8
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Differences between detach(), hide() and remove() - jQuery
... the DOM completely.
detach() is like remove(), but keeps the stored data and events associated with the matched elements.
To re-insert a detached element into the DOM, simply insert the returned jQuery set from detach():
var span = $('span').detach();
...
span.appendTo('body');
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Evaluating a mathematical expression in a string
...ppend(toks[0])
def pushUMinus(self, strg, loc, toks):
if toks and toks[0] == '-':
self.exprStack.append('unary -')
def __init__(self):
"""
expop :: '^'
multop :: '*' | '/'
addop :: '+' | '-'
integer :: ['+' | '-'] '0'..'9'+
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In Python, how do I determine if an object is iterable?
... in our code as well for this purpose, but I've lately started to get more and more annoyed by objects which only have __getitem__ being considered iterable. There are valid reasons to have __getitem__ in a non-iterable object and with them the above code doesn't work well. As a real life example we...
Convert a binary NodeJS Buffer to JavaScript ArrayBuffer
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Instances of Buffer are also instances of Uint8Array in node.js 4.x and higher. Thus, the most efficient solution is to access the buf.buffer property directly, as per https://stackoverflow.com/a/31394257/1375574. The Buffer constructor also takes an ArrayBufferView argument if you need to ...
What is the difference between an ORM and an ODM?
I am trying to figure out what the difference is between ORM and ODM, as far as I understand the concept, ORM (Object Relational Mapper) maps the relations between data, where as ODM (Object Document Mapper) deals with documents. Am I right in assuming that mySQL is an example of ORM and MongoDB is ...
Java8: Why is it forbidden to define a default method for a method from java.lang.Object
...e design issues that seems "obviously a good idea" until you start digging and you realize that its actually a bad idea.
This mail has a lot on the subject (and on other subjects too.) There were several design forces that converged to bring us to the current design:
The desire to keep the i...
On design patterns: When should I use the singleton?
...ptable" reasons to use a Singleton.
One reason that tends to come up over and over again on the internets is that of a "logging" class (which you mentioned). In this case, a Singleton can be used instead of a single instance of a class because a logging class usually needs to be used over and over ...
filters on ng-model in an input
I have a text input and I don't want to allow users to use spaces, and everything typed will be turned into lowercase.
8 An...