Optimal TSP Path with Branch and Bound

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I just wanted a bit of clarification on the above picture. I understand the general idea of building out a tree in DFS order and stopping once you come across a number bigger than you got before. For example, when the value of the path becomes $ 14$ or $ inf$ the algorithm stops because there was already a path of value $ 11$ . But, I am quite confused with regards to where these numbers are coming from (the lower bounds on the cost). For example, the path from vertex $ A$ to vertex $ B$ has length $ 1$ , but in the tree, the path from $ A$ to $ B$ has a lower bound of $ 10$ .

So, I would greatly appreciate if anyone could let me know where the numbers in the branch-and-bound search tree are coming from!

Examples of Analysis of Branch and Bound Method

I am solving a graph problem, which can be formulated as an integer programme. Based on computer experiments, it seems that the branch and bound method works well. I would like to analyse the running time, and wonder whether there have been other problems where branch and bound method was used and the theoretical bounds on the running time has been established?

On another note, if anyone knows any examples of problems where the range of possible values that a variable in a linear programme can take, I’d also be interested in.

Strategies to protect SANs in branch offices in risky places

A company has several remote branch offices located in relatively dangerous places, such as Iraq, and I’m looking into strategies to secure the SAN in the event of theft, looting or rogue admins. Some of these offices are mobile, moving locations every couple of months.

Basically, the goals are:

  1. Prevent data from the SAN falling into the hands of others
  2. Prevent the destruction of data

Each site has:

  • A VPN, providing access to a central data centre in the USA (over a satellite link, sometimes as low as 4MB/s)
  • A local, highly-available ESXi cluster (note the vCentre server is located in a central data centre in Europe)
  • Virtual SAN storage (using StorMagic)
  • No local backups; backups are done remotely to a central data centre in Europe. The satellite links are often slow, and sites can sometimes be without access for several hours

At present, no data is encrypted – for this question, that’s what I want to focus on.

Do you have any suggestions? Should we encrypt at the SAN level, the vSphere level, the OS level? How should keys be managed?

Branch and scope globally unique identifiers

Say we are working with a Prolog-like system where variables are dynamically created in different branch contexts and scopes, yet these variables are also globally viewable by the system regardless of the current context. Is there a way to label each variable with a unique scope ID which can be used to determine if the variable assignment is considered live (i.e. not discarded by backtracking) in the current context.

Naively, you could create a bitstream of left/right branch decisions, but the memory usage would be really excessive and also have bad query time for liveness. Can anything better be done?

How to stop current branch of actions but not terminate the whole flow

I have 4 streams of actions which filter out selections: 1-10k 11-30k 30-99k 100k+

On my previous question I wanted to avoid heavily nesting items, that has been achieved. Now, I am faced with the problem where, I have 3 Streams that are FALSE and one is TRUE but I don’t want to Terminate the whole flow just because they are false.

So, I have a workaround of “Do Until” which will run infinitely, until the flow is forced to terminate.

I was wondering, are there any other methods that are recommended?

Another I can think of is Sending an Email asking for a response which never gets answered. Neither are ideal solutions, but suffice. Are there official ways of performing this? Something like, end this “line of inquiry” if condition is false?

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How can I get rid of a dependency in a single branch?

I am working on an API solution, split in three projects:

  • API
  • Domain
  • DataAccessLayer

I have created an interface, in the Domain project, ICustomerRepository, with a single method:

Domain.Customer GetCustomerById(int customerId) 

The DataAccessLayer implements this interface with a FooCustomerRepository.

Foo is a application-specific DB provider. It provides an .NET assembly, which is referenced in the DataAccessLayer project.

The API controller only uses the interface, which is injected through Unity:


 public class ApiController : Controller  {     public ApiController(          Domain.ICustomerRepository customerRepository)     {          ...     } } 


public static void RegisterTypes(IUnityContainer container) {     container.RegisterType<Domain.ICustomerRepository, DataAccessLayer.FooCustomerRepository>(); } 

In order to get it to work, I have to create a dependency to DataAccessLayer in my API project, and therefore to the Foo assembly.

I have been assigned an intern to work on this project. For red tape reasons, I will not be able to have Foo installed on his computer before a long while, but I would like him to work on the API project, and be able to compile it.

A fake repository returning dummy data is available in the API project.

How can I achieve this?

I have thought about creating a new branch, and removing anything to do with DataAccessLayer, including the UnityConfig and the references, but it seems like it would be a nightmare to merge back (since as you can imagine, the actual project is a bit more complex).

Is that the only way to go?

Branch Specific pricing in magento 2

Need to setup branch specific pricing . 600 Branches available each branch has same products but different pricing . Need to use zipcode to differentiate users and navigate them to corresponding branches/products . How can we do this in magento 2 ? How much customization needed ? is it possible to create 600 store views based on branches and set different price same product in different store views ? is it efficient ?

Understanding the difference of branch between SVN and Git

I am a user of SVN and now I am learning Git.

In SVN I usually checkout on my local machine a repo, which includes all branches in my project and I used to select the folder for my branch I am interested to and work there.

I see a difference using Git.

Currently I am cloning a repo and clone a specific branch using gitk.

The project folder contains only the content for that branch and I cannot see all branches as in SVN, which is a little confusing for me.

I cannot find an easy way to see all branches in my local repository using Git.

  • I would like to know if the Git process I described is “standard” and some how correct or I am missing something.

  • Also I would like to know how to handle a process where I need to work on two branches at the same time in case, for example, I need to make an hotfix on master but keep the content of another branch too.

  • What is a recommend name conventions to make the folders which include the branch cloned from the repo in Git, example myproject-branchname?