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Linear Regression and group by in R
...a linear regression in R using the lm() function. My data is an annual time series with one field for year (22 years) and another for state (50 states). I want to fit a regression for each state so that at the end I have a vector of lm responses. I can imagine doing for loop for each state then do...
How do I import .sql files into SQLite 3?
...tabase.db
Also, your SQL is invalid - you need ; on the end of your statements:
create table server(name varchar(50),ipaddress varchar(15),id init);
create table client(name varchar(50),ipaddress varchar(15),id init);
sh...
What is Serialization?
...with Object-Oriented Programming (OOP) and would like to know: what is the meaning of serialization in OOP parlance?
15 Ans...
Parameterize an SQL IN clause
How do I parameterize a query containing an IN clause with a variable number of arguments, like this one?
40 Answers
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Entity Framework - Include Multiple Levels of Properties
The Include() method works quite well for Lists on objects. But what if I need to go two levels deep? For example, the method below will return ApplicationServers with the included properties shown here. However, ApplicationsWithOverrideGroup is another container that holds other complex objects. Ca...
Visual Studio replace tab with 4 spaces?
...
Just to share that is still the same for Visual Studio 2013.
– James
Feb 24 '15 at 19:42
6
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Does Spring @Transactional attribute work on a private method?
If I have a @Transactional -annotation on a private method in a Spring bean, does the annotation have any effect?
8 Answe...
What is Python buffer type for?
...f the first byte
>>> s[1] = 5 # set the second element in s
>>> t[0] # which is now also the first element in t!
'\x05'
This can be very helpful if you want to have more than one view on the data and don't want to (or can't) hold multiple copie...
C libcurl get output into a string
...CURLOPT_WRITEFUNCTION, myfunc);
The callback will take a user defined argument that you can set using curl_easy_setopt(curl, CURLOPT_WRITEDATA, p)
Here's a snippet of code that passes a buffer struct string {*ptr; len} to the callback function and grows that buffer on each call using realloc().
#...
PHP multidimensional array search by value
...now that if you are using === operator compared types have to be exactly same, in this example you have to search string or just use == instead ===.
Based on angoru answer. In later versions of PHP (>= 5.5.0) you can use one-liner.
$key = array_search('100', array_column($userdb, 'uid'));
Her...