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I want to achieve the BAB tree structure like,
I am trying to use R, matlab and CPLEX, but cannot figure it out.
In C++ you could retrieve the Branch-and-Bound (B&B) information via a Callback. In simple terms, a callback is an instruction that is declared before optimisation to CPLEX and whenever the condition is met during the B&B, CPLEX will stop and enter the callback to execute your code.
As you can see this is exactly what you need, although most people use them to impose cuts or valid inequalities as a walkaround to avoid setting a priori an exponential number of constraints, and only add them on-the-go. Nothing stops you from declaring a very general condition that will be satisfied at every node of the tree, and then extract all the information you might need and construct the tree based on that info. You only have to go read CPLEX documentation to determine which is the more suitable callback depending on your problem and need.
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I was kind of wondering,how R language works internally when we type some command..
Say License()
As per my understanding,R language is made of packages,When we execute some command,it invokes the Right package,i was not able to find some documentation supporting this..
Research done from side:
1.closest i could get is below link
https://cran.r-project.org/doc/contrib/Paradis-rdebuts_en.pdf
2.I searched using "How R Language works internally",but i could not get any relevant results..
Below is how SQLServer executes a query from starting to end ,i am looking to see similar kind of documentation/any pointers for R
please let me know if you have any pointers
The notion that the R language is "made of packages" is inaccurate. It is made of commands, operators and functions, like other programming languages. Those commands are grouped into namespaces which comprise commands that belong to the same topic. A package provides a set of specific commands (and sometimes other objects, like sample data) grouped into a namespace. By loading a library (there are subtle semantic differences between a library and a package) the namespace of the package becomes available in the global environment, thereby making these commands directly accessible.
On the suggestion of #CapelliC here is a fully typed answer.
The internals of R are included in the document: https://cran.r-project.org/doc/manuals/r-release/R-ints.html
It is not an easy read, but covers all of the detail. My advice would be search the document if you have a specific query...
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I'm writing relatively small, but not simple networking library which is going to be used at least from C,java,python,ruby and C#. Is there a way to make go bindings to the other languages the way in can be done form C? If not is there other way?
Right now, you can't write libraries in Go that can be used in other languages. Go has a runtime environment that does a lot of things (like sheduling go-routines, collecting garbage) for you. This runtime environment is written under the assumption that it controls the whole program. This assumption does not hold if Go code would be used from inside another language, as the Go library cannot influence the binary that uses it.
I imagine that a JSON service would do what you describe.
Have a look at the json test for a simple example
It wouldnt matter what languages you used to set and get data from your app
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Can you please provide a specific situation illustrating when a for loop might work more effectively than the more commonly cited apply suite of solutions?
If the results of the previous computation are used in the next computation, it is appropriate to use a for loop, since this behavior is difficult to replicate with lapply (you would have to use something like Reduce). R is not necessarily slow with for loops, merely with memory allocation (which is easy to get wrong with for loops). See Chapter 2 of the R Inferno.
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I heard this a lot when talking about software engineering and abstract data types, what does this do? Can anyone give me a concrete example of this concept?
A representation invariant is a condition concerning the state of an object. The condition can always be assumed to be true for a given object, and operations are required not to violate it.
In a Deck class, a representation invariant might be that there are always 52 Cards in the deck. A shuffle() operation is thus guaranteed not to drop any cards on the floor. Which in turn means that someone calling shuffle(), or indeed any other operation, does not need to check the number of cards before and after: they are guaranteed that it will always be 52.
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My software is a video-audio converter and video cutter. I have used Qt(compiled from source) and ffmpeg (compiled from source). I have to prepare System Usage Specification outline and Specify Usage patterns of the system and indicate it using Run charts / Histograms. I am told to use Winrunner for this purpose. I don't know exactly what to do. Please help.
I never heard about 'System Usage Specification', this must be a terminology specific to your company.
A wild guess would be that it's something close to the Use Case diagram of UML, to define what the users can do and which action they have to perform to lead them to the expected result.
Sounds like a uggly word for "handbook" or "usage guide" from the pov of a end-user (though I never heared of that specific term)