Grouping n points into groups of size m with objective to have least traveling distance in each group


  • There are “n” jobs which are distributed over the city.
  • Company has “k” available workers.
  • Each worker can do “x” jobs per day.
  • “x” is dependent to the worker skills and the distance he travels each day so it’s not a constant.
  • Workers have no initial traveling distance.
  • “s” is a set that shows each workers can do how many jobs based on the distance he travels
  • “d” is the number of days that takes for company to do all the jobs.

Objective: Minimize the “d”

I know this problem is probably NP-hard so I don’t need the exact answer. I think it’s kinda a variation of Traveling salesman problem combining with scheduling and assignment problems.

My algorithm for this problem is to “some how” efficiently ( of course not the most efficient way ) grouping the jobs based on their traveling distance in the groups in to groups of “m” which is the mean of set “s”. Then after each day rerun the algorithm to get better results.

My question is what is the best way to do that grouping? Anyway if you know a better algorithm I would be more than happy to know them.

Cluster or shared collections in logical aggregate groups

We would have date specific trading data for about 10M trades – each day’s data comprising ~1T data in different collections like market,trade,settlements etc.
Since we would not need more than 3 days data at any point of time – intention is to delete all data pertaining to T-3 or more.
There would be 2 possible options:

1.Each trading  day being represented as a separate database  - with the standard set of collections viz marketdata,trade,settlementdata in each database 2.Every collection being appended with the date viz marketdata_10032019,marketdata_10042019 etc  

The first option seems better as:

1. much cleaner in terms of maintenance - just dropping the obsolete databases,rather than scanning collections by name.  2. Dynamic collection names as in second option puts severe restrictions in aggregation possibilities - mongo aggregation does not support dynamic names.  

Would appreciate further views – based on performance,concurrency,scalability,clustering/sharding,maintenance etc

I do not see any question that addresses the used case of trying to cluster/maintain on the basis of a second-level logically aggregated grouping of collections based on date (or any other)

Best UI pattern to allow the user to assign 1 level nested items to two groups

My issue is something similar to this one – Best UI pattern for letting a user assign items to groups

I am looking for a good UI design for mapping items between 2 groups (only one-to-one mapping). These items can be under a parent or by itself. I thought of drag-and-drop/ having checkboxes (or switch like) to turn on for any one group.

Items Group 1 Group 2

Item A
Item A1 checkbox checkbox

Item B checkbox checkbox

Does the NSO Group’s Pegasus malware compromise chats and voice calls in Signal as well?

I am aware that the Pegasus malware is capable of extracting contact lists, ordinary text messages, switching on microphone / camera remotely etc. Is it also capable of extracting the contents of communications made via Signal? This is of particular importance for people who may be targeted by Pegasus, since Signal is becoming so widely used as a secure channel of communication…

My question is primarily concerned with Android users, but if iOS can also be covered that would be great.

Yahoo groups is going away: can I use Mathematica to download the old messages?

It looks like all the old email messages from my group are stored in web pages with URLs that look like this:


That’s email number 19291, and the others have the same form but different numbers at the end. What I am hoping to do is to grab all the old messages. The problem is that:

ans = Import[page] 

returns stuff that begins with “Sorry, an error occurred while loading the content.” From the look of it, I’m guess that the problem is that my Import statement is not “logged in” to the website, and so it is rejecting the request. Does anyone know how to “log in” to the yahoo site (to enable downloading of the old emails)?

SharePoint Search Query – Filter item by user & groups from the current user

In a web part, I wanted to show only items that people had permissions on. I know I can stop inheriting permissions on the list and give them unique permissions, but that’s not what our client wants. So we created a column of people and groups (linked to Azure AD groups) we wanted to be able to filter in the search query only items where the user belonged to the group the item is associated with. Is this possible?

Thank you.

Need script to list Groups by Team Site

I am trying to find PowerShell scripts that do the following:

  1. List all TeamSites.

  2. List all TeamSites, Groups that belong to that TeamSite with their permissions.

  3. List all TeamSites, Groups that belong to that TeamSite with their permissions as well as the users that belong to those groups (grouped by group).

This would be for SharePoint online.

Is this possible? Any help would be greatly appreciated.