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ASP.NET MVC - Attaching an entity of type 'MODELNAME' failed because another entity of the same type
...'Modified'. Before changing the state, the state is set to 'Detached' but calling Attach() does throw the same error. I'm using EF6.
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What is the difference between linear regression and logistic regression?
...e, and greater than 1 whereas probability can not. As regression might actually
produce probabilities that could be less than 0, or even bigger than
1, logistic regression was introduced.
Source: http://gerardnico.com/wiki/data_mining/simple_logistic_regression
Outcome
In linear regression, the...
Difference between a theta join, equijoin and natural join
...
A theta join allows for arbitrary comparison relationships (such as ≥).
An equijoin is a theta join using the equality operator.
A natural join is an equijoin on attributes that have the same name in each relationship.
Additionally,...
Count how many files in directory PHP
...n you include other directories within that directories and so on to count all files and exclude directories from the count?
– The Bumpaster
Jul 2 '16 at 13:40
1
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Approximate cost to access various caches and main memory?
...xample, check page 22 for some timings & cycles for example).
Additionally, this page has some details on clock cycles etc. The second link served the following numbers:
Core i7 Xeon 5500 Series Data Source Latency (approximate) [Pg. 22]
local L1 CACHE hit, ...
How does C compute sin() and other math functions?
...on in C, contributed by IBM. Since October 2011, this is the code that actually runs when you call sin() on a typical x86-64 Linux system. It is apparently faster than the fsin assembly instruction. Source code: sysdeps/ieee754/dbl-64/s_sin.c, look for __sin (double x).
This code is very complex. N...
Reference: What is variable scope, which variables are accessible from where and what are “undefined
... be in the global scope in a.php doesn't necessarily mean they are, it actually depends on which context that code is included/executed in.
What about functions inside functions and classes?
Every new function declaration introduces a new scope, it's that simple.
(anonymous) functions inside func...
Does C have a “foreach” loop construct?
Almost all languages have a foreach loop or something similar. Does C have one? Can you post some example code?
12 Answer...
libpthread.so.0: error adding symbols: DSO missing from command line
...nd line after the object files being compiled:
gcc -Wstrict-prototypes -Wall -Wno-sign-compare -Wpointer-arith -Wdeclaration-after-statement -Wformat-security -Wswitch-enum -Wunused-parameter -Wstrict-aliasing -Wbad-function-cast -Wcast-align -Wstrict-prototypes -Wold-style-definition -Wmissing-pr...
What is the difference between shallow copy, deepcopy and normal assignment operation?
...ble towards the existing object. The docs explain the difference between shallow and deep copies:
The difference between shallow and deep copying is only relevant for
compound objects (objects that contain other objects, like lists or
class instances):
A shallow copy constructs a new...