Questions regarding efficient storing and representing data within a software application.

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3
votes
2answers
207 views

MaxHeap-like data structure supporting max AND min, also decrease-key (yes decrease-key)

For the purpose of implementing an optimization algorithm (finding the minimum of a multivariate function) I want to create a data structure that supports the following operations: load from array ...
0
votes
0answers
126 views

Enterprise Mashups. A good approach for .net

I'm in the middle of trying to talk our management into letting us do a portal that sits across the many, many systems that we use. I believe in using the best tool for the job so we have a good ERP, ...
0
votes
0answers
152 views

scrabble solving with maximum score

I was asked a question You are given a list of characters, a score associated with each character and a dictionary of valid words ( say normal English dictionary ). you have to form a word ...
0
votes
5answers
1k views

Fastest way to determine if a value is in a list?

I'm aware there may not be a good solution to this problem. I'm looking for a fast algorithm that determines whether or not a value (let's say an integer) exists in a set of values, however I need the ...
0
votes
0answers
152 views

How to model dynamic table schema in .Net code

I am preparing to do an upgrade of a fairly large program that is currently written entirely in MS Access, both GUI and data (code and data in separate files). One of the key features of the product ...
1
vote
2answers
90 views

Passing context around AST nodes

I have various objects inside my AST, such as IfBlock, FunctionBlock, LogicExpression, etc. All of those objects share a context, which is basically a hashmap with some variables. It's a very simple ...
2
votes
0answers
53 views

IRLBot Paper DRUM Implementation - Why keep key, value and auxiliary buckets seperate?

Repost from here as I think it may be more suited to this exchange. I'm trying to implement DRUM (Disk Repository with Update Management) as per the IRLBot paper (relevant pages start at 4) but as ...
1
vote
2answers
2k views

What are the advantages of linear probing over separate chaining or vice-versa when implementing hash tables?

I've been brushing up on algorithms and reviewed these two methods of implementing hash tables. It seems like they largely have similar performance characteristics and memory requirements. I can ...
0
votes
1answer
129 views

Any good data structure to perform efficient lookup and modification operations about what are the shapes containing the current cursor position

I think I'm facing a pretty common issue but cannot remember which solution is the most suitable one. Let's put it that way: I can, in a, certain, given, language get some events anytime the user is ...
1
vote
2answers
281 views

Non-fixed-size Fenwick Tree implementation

I'm planning to implement a non-fixed-size Fenwick tree. That is, a Fenwick tree that allows interleaving range queries with adding/removing elements. All implementations and samples I've seen so far ...
2
votes
1answer
305 views

When designing a data structure, should I implement very inefficient operations for convenience?

(I've added the .NET tags because the data structures are for .NET, and this question should be considered in the context of the conventions for that platform.) I'm writing a library of immutable and ...
4
votes
3answers
146 views

Is storing data directly in a list node better than storing a pointer to data?

Suppose we have two different doubly-linked list structures: One has content of the node embedded directly in the node: struct Content { // some stuff }; struct Node { struct Node *next; ...
1
vote
1answer
225 views

Is a linked list an actual data structure?

I hear conflicting sides from this topic. I was under the impression that a linked list was a way to implement a data structure (stack, queue), not actually a data structure.
1
vote
1answer
199 views

C# Structs, 16 byte rec. - Are getters and setters included in that?

I was reading into the nitty-gritty of structs in C# here: "C Fundamentals, The differences between struct and class." and at the very bottom it mentions keeping a struct below 16 bytes. I looked ...
1
vote
2answers
162 views

Efficient datastructure to create size-limited dictionary

I need a class that acts like a dictionary but will constrain the total number of key/value pairs it contains. For instance, let's say the maximum number of entries is 1000 and the class already ...
0
votes
1answer
111 views

What's the algorithm should I use for seeing how well 2 strings match?

Suppose I have 2 strings: string1 = "home/lisa/Music/some_files/01.05 - Garden Ground.mp3" string2 = "Music/Jim Smith/Unknown/(Deluxe Version/Garden Ground).mp3" string4 = "Music/Jim Smith/Unknown/00 ...
4
votes
4answers
365 views

Why use an enum to determine node type in a parse tree?

The Sun Compiler Tree API uses an interface called Tree as the parent of all the different kinds of parse tree nodes (assignments, if-statements, class declarations, etc.). A part of this interface is ...
1
vote
1answer
267 views

Best Data structure for implementation of dependent drop-downs

I want to implement dependent drop-down feature on a web page in my website containing the following drop-downs: User's group name Group events (dependent drop-down) Locations (dependent drop-down) ...
0
votes
1answer
170 views

Injectable, Poppable Stack

Background A project involves converting a relational expression map (rxm) to an XML/SQL statement. The map resembles: root > people, # "root" keyword starts the document ...
0
votes
2answers
401 views

Storing and retrieving simple data within a framework

I'm determined to get a decent answer to this, because while I have my own approach (constants) I'm not convinced I'm doing it as efficiently as I could be. So I'm editing the entire question, to ...
1
vote
1answer
66 views

Difficulty in deciding correct data structure

Two objects are interacting (Object Alpha, Object Beta) Each contain a point (x,y) which will be used to make comparisons, among other things. Object Alpha's point (x,y) attribute is dynamic and ...
1
vote
5answers
281 views

What would an anti-tree look like?

I am wondering if the Tree data structure has a dual. Something that 'starts at the leaves and converge on the root'. If so, what's it called? Maybe I'm missing something completely obvious. I could ...
2
votes
1answer
82 views

How Javascript Engines access/lookup property names?

How Javascript Engines access/lookup property names? what kind of associative array (data structure or search/lookup algorithm) did they use? (for V8, TraceMonkey, JSC, and Rhino) For example, in C++ ...
1
vote
0answers
214 views

Optimal data structure for binary data/Java

I have several input formats mostly restricted to geotiff and some proprietary binary formats. I import them into my program and then need to export them into various other data formats (also binary) ...
0
votes
2answers
99 views

Approaches to get stats like average latency in last N seconds

I am receiving messages with latency information (LI, {date, latency}). For statistical reasons: (I am open to approx. approaches, stats monitor will be updated in 6-60 seconds) I want to monitor (...
0
votes
3answers
1k views

How to save complex data to file/disk?

I am working on a side project for a small business owner (my father) and part of the requirements for the application include saving customer and job related data in a way that it can easily be ...
1
vote
1answer
122 views

Multitenancy and nested set trees

The application I work on utilizes nested sets1 to represent tree structures within our database. We need to expand a particular area of access control to support multiple clients who should not be ...
0
votes
2answers
31 views

Making sure loaden (non default) config is valid

I'm writing a device Software in which the device must handle much data. Therefore it has a database, either on NV-Ram (Non-volatile memory) or a SD-Card. Due there's a DB which I can use, I also use ...
1
vote
4answers
161 views

What do polynomial algorithms entail?

From here, I know it is that an algorithm that... ...is said to be solvable in polynomial time if the number of steps required to complete the algorithm for a given input is O(n^k) for some ...
0
votes
1answer
154 views

Application with really dynamic data structure [closed]

Well, I'm on the verge of this project that really puzzled me. The situation is, in our office, we have a department that collect data about the corporate performance indicators from all across the ...
1
vote
2answers
112 views

Structuring data to represent a tree with squirrels

What I want to represent Let's assume I have several schemas of the following kind: It is a tree on which positions of squirrels are represented by a blue dot. The number of bifurcations differ ...
0
votes
1answer
3k views

How to remove a middle element from queue?

I had a question, about how to remove an element from middle of the queue , without disturbing the order of other elements. E.g. Queue before operation:- <| a b c d e |< Queue after ...
8
votes
2answers
693 views

How do personal assistants typically generate sentences?

This is sort of a follow up to this question about NLG research directions in the linguistics field. How do personal assistant tools such as Siri, Google Now, or Cortana perform Natural Language ...
4
votes
2answers
106 views

Is it a good idea to have a database row that represents an unknown value within a system [closed]

We have two systems, System A imports a list of sports events from system B, it only wants to import the events we will be providing live data for, the filter used to hide events that we are not ...
-1
votes
2answers
320 views

Efficiently save big data structures [closed]

I need to save big data structure (Tree with specific nodes) into file efficiently. Data is always changing, so I need to rewrite whole data structure very often, so simple serialization is not good ...
-1
votes
1answer
142 views

What are some hashmaps we can easily implement? [duplicate]

At many places, I read that we can use HashMap here for O(1) search. Actually, I want to ask how I can implement easy hashmaps which can satisfy this property. Can anyone tell few hashmaps including ...
1
vote
1answer
212 views

Where to put data for tree structure which every node requires?

I have a quad-tree structure where each node has some of its own data, but there is also data which applies to the tree as a whole. I'll explain my current solution and I would appreciate feedback on ...
2
votes
1answer
230 views

How to make max-heap stable with counter and account for counter overflow?

Generally I need size-efficient data structure similar to std::priority_queue but stable (preserving order of insertion). By adding just 4 bytes to the object I could have 1 byte serving as priority ...
4
votes
1answer
519 views

Using macros to implement a generic vector (dynamic array) in C. Is this a good idea?

So far I have only done personal projects at home. I hope to get involved in some open source project some time next year. The languages I that have been using the most are C and C++. I have used both ...
2
votes
2answers
250 views

Is embedding data in a executable considered a good practice?

Embedding data (such as images) in a executable seems to have a few advantages, like easier distribution of the executable and easier compatibility with different OSes. But, is it a good practice? ...
4
votes
1answer
300 views

Why define struct in variable?

Consider the following program: Many people when they want to use a struct, they create a new variable as: struct structureName variableName While it works when you just define it as: ...
4
votes
2answers
390 views

Merge directed acyclic graphs minimizing number of nodes

I have some DAGs (directed acylic graphs) and I want to merge them in order to minimize the number of nodes (we could say that every node has a cost, while edges are free). These four different DAGs (...
5
votes
2answers
395 views

Why Do B+ Trees Have a Minimum Occupancy of 50%?

As far as I can tell, the basic operations (add, delete, search) on a B+ Tree would function the same if minimum occupancy was 1, or 1/3, or any other function on node size. All the sources available ...
0
votes
1answer
473 views

calculating the average of a value over a month [closed]

I am working on a project right now that is having me calculate monthly interest on a bank account. The way the interest is supposed to be calculated is as follows: Use the daily average to calculate ...
0
votes
1answer
68 views

Efficient storing and multidirectional lookup of hierachical data

I make a game and among others I have nations, provinces, tiles and armies. Each army belongs to exactly one tile, each tile belongs to exactly one province, each province to exactly one nation. I ...
0
votes
1answer
101 views

Handling the process of large-scale lists [closed]

What are the efficient ways to process huge lists (+10 millions), and things to consider while manipulating huge lists. First question, when should I use recursion, and when I shouldn't. In both ...
0
votes
1answer
113 views

Method ordering

This is the type of question that one would probably get in an exam, but now it happens to be in the real word. :-) I would appreciate some advice regarding the datastructure/algorithm that can be ...
2
votes
1answer
283 views

Data structure well suited for duplicate entries

I'm in the process of getting to know (modern) filesystems. As part of it, I came across log structured filesystems that also handle allocations in a log structured way. I wonder how they handle ...
1
vote
1answer
188 views

Is it a good idea to use bloom filters for this scenario?

I have a theoretical social network where two people, A & C, can become friends if and only if, they have a common friend B amongst them. The simplest solution is to iterate over the two lists ...
1
vote
3answers
2k views

Database design: 4 types of users but have different functionality , separate or one table?

I have 4 types of users: Admins , normal user , company , service provider admins and normal user share some attributes (id .first name ,last name ,phone ,mail) company and service provider share ...