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Import multiple csv files into pandas and concatenate into one DataFrame
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If you have same columns in all your csv files then you can try the code below.
I have added header=0 so that after reading csv first row can be assigned as the column names.
import pandas as pd
import glob
path = r'C:\DRO\DCL_rawdata_files' # use you...
Difference between Django's annotate and aggregate methods?
...rage_price': 34.35}
Returns a dictionary containing the average price of all books in the queryset.
Annotation
>>> q = Book.objects.annotate(num_authors=Count('authors'))
>>> q[0].num_authors
2
>>> q[1].num_authors
1
q is the queryset of books, but each book has been...
java.sql.SQLException: Incorrect string value: '\xF0\x9F\x91\xBD\xF0\x9F…'
...ead:
For a supplementary character, utf8 cannot store the character at all,
while utf8mb4 requires four bytes to store it. Since utf8 cannot store
the character at all, you do not have any supplementary characters in
utf8 columns and you need not worry about converting characters or
losi...
Unable to load SOS in WinDbg
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The CLR runtime dll was renamed to clr.dll with .NET 4. So in order to load the correct version of SOS you need to adjust your .loadby command. I.e.
.loadby sos clr
Also, if you're on 64 bit, you should install the 32 bit version of Debugging Tools for Windows as well in order to deb...
javac : command not found
...install java-devel or java-1.6.0-openjdk-devel, which both include javac.
By the way: you can find out which package provides javac with a yum search, e.g.
su -c 'yum provides javac'
on more recent releases of CentOS e.g. 6 the command changes to
su -c 'yum provides */javac'
Another note: usi...
How to install Xcode Command Line Tools
How do I get the command-line build tools installed with the current Xcode/Mac OS X v10.8 (Mountain Lion) or later?
13 Answ...
Javascript !instanceof If Statement
...he outside.
if(!(obj instanceof Array)) {
//...
}
In this case, the order of precedence is important (https://developer.mozilla.org/en-US/docs/JavaScript/Reference/Operators/Operator_Precedence). The ! operator precedes the instanceof operator.
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C# Lazy Loaded Automatic Properties
...a solve to your problem. Basically the idea is a property that will be set by a function at first access and subsequent accesses will yield the same return value as the first.
public class LazyProperty<T>
{
bool _initialized = false;
T _result;
public T Value(Func<T> f...
How to find common elements from multiple vectors?
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Highly active question. Earn 10 reputation in order to answer this question. The reputation requirement helps protect this question from spam and non-answer activity.
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Why use Ruby's attr_accessor, attr_reader and attr_writer?
...write classes which will work correctly no matter how their public API is called.
class Person
attr_accessor :age
...
end
Here, I can see that I may both read and write the age.
class Person
attr_reader :age
...
end
Here, I can see that I may only read the age. Imagine that it is set ...