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What is attr_accessor in Ruby?
...me # => no method error
Obviously we never defined method name. Let's do that.
class Person
def name
@name # simply returning an instance variable @name
end
end
person = Person.new
person.name # => nil
person.name = "Dennis" # => no method error
Aha, we can read the name, but ...
how do you filter pandas dataframes by multiple columns
...
Using & operator, don't forget to wrap the sub-statements with ():
males = df[(df[Gender]=='Male') & (df[Year]==2014)]
To store your dataframes in a dict using a for loop:
from collections import defaultdict
dic={}
for g in ['male', 'f...
Could not establish trust relationship for SSL/TLS secure channel — SOAP
I have a simple web service call, generated by a .NET (C#) 2.0 windows app, via the web service proxy generated by Visual Studio, for a web service also written in C# (2.0). This has worked for several years, and continues to do so at the dozen or so places where it is running.
...
Padding is invalid and cannot be removed?
...een using the example provided my msdn for encrypting and decrypting an XmlDocument using the Rijndael algorithm. The encryption works fine but when I try to decrypt, I get the following exception:
...
boolean in an if statement
...to true. No other truthy value will satisfy it.
On the other hand if you do this:
if (someVar == true)
Then, what Javascript will do is type coerce true to match the type of someVar and then compare the two variables. There are lots of situations where this is likely not what one would intend....
'and' (boolean) vs '&' (bitwise) - Why difference in behavior with lists vs numpy arrays?
...are logically True. This facilitates the common use case where you want to do something if a list is empty and something else if the list is not. Note that this means that the list [False] is logically True:
>>> if [False]:
... print 'True'
...
True
So in Example 1, the first list is ...
Is it possible to make the -init method private in Objective-C?
...methods. Any message can be sent to any object at any time.
What you can do is throw an NSInternalInconsistencyException if your -init method is invoked:
- (id)init {
[self release];
@throw [NSException exceptionWithName:NSInternalInconsistencyException
...
What Vim command(s) can be used to quote/unquote words?
...ou are truly set against using it, here are some examples for what you can do. Not necessarily the most efficient, but that's why surround.vim was written.
Quote a word, using single quotes
ciw'Ctrl+r"'
ciw - Delete the word the cursor is on, and end up in insert mode.
' - add the first quote.
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Can someone explain in simple terms to me what a directed acyclic graph is?
... to me what a directed acyclic graph is? I have looked on Wikipedia but it doesn't really make me see its use in programming.
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How can I pop-up a print dialog box using Javascript?
...automatically when the user arrives at the print-friendly page. How can I do this with javascript?
8 Answers
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