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

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-3
votes
1answer
576 views

map data structure in pacman [closed]

I am trying to make a pacman game in c#. I have done some basic work and have previously replicated games like copter-it and minesweeper. I am confused about how to implement the map in pacman. Which ...
5
votes
3answers
323 views

Generating Deep Arrays: Shallow to Deep, Deep to Shallow or Bad idea?

I'm working on an array structure that will be used as the data source for a report template in a web app. The data comes from relatively complex SQL queries that return one or many rows as one ...
4
votes
2answers
622 views

Which design better when use foreign key instead of a string to store a list of id

I'm building online examination system. I have designed to table, Question and GeneralExam. The table GeneralExam contains info about the exam like name, description, duration,... Now I would like to ...
4
votes
2answers
359 views

Fast set indexing data structure for superset retrieval

I am given a set of sets: {{a,b}, {a,b,c}, {a,c}, {a,c,f}} I would like to have a data structure to index those sets such that the following "lookup" is executed fast: find all supersets of a given ...
5
votes
2answers
894 views

Data structure for pattern matching

Let's say you have an input file with many entries like these: date, ticker, open, high, low, close, <and some other values> And you want to execute a pattern matching routine on the ...
0
votes
3answers
182 views

I need some help creating a non-binary tree (or some other data structure that will better solve my problem)

I have about ten lists of numbers and some strings. Each list has about <= 30K lines. Each line on a list has a distinct number. I need to build an efficient way of finding all the lines in each ...
5
votes
2answers
670 views

Patterns for a tree of persistent data with multiple storage options?

I have a real-world problem which I'll try to abstract into an illustrative example. So imagine I have data objects in a tree, where parent objects can access children, and children can access ...
30
votes
7answers
5k views

When to use DAG (Directed Acyclic Graph) in programming?

I recently found a framework named ecto. In this framework, a basic component named "plasm", which is the ecto Directed Acyclic Graph.In ecto, plasm can be operated by ecto scheduler. I am ...
6
votes
1answer
267 views

How to design data structures for sharding?

When designing data structures for an application, what are some best practices to make sure it can be sharded? In particular, which of the following is better: Creating relationships in databases ...
6
votes
1answer
1k views

What is the usage of Splay Trees in the real world?

I decided to learn about balanced search trees, so I picked 2-3-4 and splay trees. What are the examples of splay trees usage in the real world? In this Cornell: ...
3
votes
2answers
301 views

I have data that sends in “bursts” of 100 records with a significant delay. How do I structure my classes for multithreading?

My datasource sends information in 100 batches of 100 records with a delay of 1 to 3 seconds between batches. I would like to start processing data as soon as it's received, but I'm not sure how to ...
3
votes
1answer
651 views

How should I architect my Model and Data Access layer objects in my website?

I've been tasked with designing Data layer for a website at work, and I am very interested in architecture of code for the best flexibility, maintainability and readability. I am generally acutely ...
1
vote
2answers
470 views

Count function on tree structure (non-binary)

I am implementing a tree Data structure in c# based (largely on Dan Vanderboom's Generic implementation). I am now considering approach on handling a Count property which Dan does not implement. The ...
1
vote
6answers
3k views

Serializing Data Structures in C [closed]

I've recently read three separate books on algorithms and data structures, tcp/ip socket programming, and programming with memory. The book about memory briefly discussed the topic of serializing data ...
5
votes
2answers
235 views

Data structures for storing finger/stylus movements in drawing application?

I have a general question about creating a drawing application, the language could be C++ or ObjectiveC with OpenGL. I would like to hear what are the best methods and practices for storing strokes ...
2
votes
1answer
207 views

2D grid with multiple types of objects

This is my first post here in programmers.stackexchange (I'm a regular on SO). I hope this isn't too general. I'm trying a simple project to learn Java from something I've seen done in the past. ...
2
votes
1answer
152 views

Separating validation from persistence in models?

Models in an MVC application gets kind of hard to test when validation of data and persistence of data is baked together in the model. I would like to test those separately to prevent doing ...
2
votes
3answers
359 views

Internal Mutation of Persistent Data Structures

To clarify, when I mean use the terms persistent and immutable on a data structure, I mean that: The state of the data structure remains unchanged for its lifetime. It always holds the same data, ...
6
votes
1answer
149 views

Unit testing a text index

Consider a text index such as a suffix tree or a suffix array supporting Count queries (number of occurrences of a pattern) and Locate queries (the positions of all the occurrences of a pattern) over ...
5
votes
2answers
665 views

Efficient Data Structure for holding a graph

Problem Link - http://opc.iarcs.org.in/index.php/problems/NUMTRIPLE In my opinion, the problem can be solved by a data structure, that shows how each number is connected to another, and via recursion ...
3
votes
1answer
293 views

Amazon Kindle - Whispersync implementation?

For those who are not aware of Kindle's whispersync, here is how it works (from amazon.com): "...Whispersync synchronizes the bookmarks and furthest page read among devices registered to the same ...
0
votes
1answer
50 views

Create association between informations

I deployed a project some days ago that allow to extract some medical articles using the results of a questionnaire completed by a user. For instance, if I reply on questionnaire I'm affected by ...
1
vote
2answers
673 views

Does the Head(start) pointer of Doubly Linked list points previously to the tail(last) node

I have one question in my mind that in case of circular doubly linked list the head pointer of the doubly linked list also logically point to the next pointer of the tail node of the linked list and ...
2
votes
1answer
4k views

Most efficient Implementation a Tree in C++

I need to write a tree where each element may have any number of child elements, and because of this each branch of the tree may have any length. The tree is only going to receive elements at first ...
1
vote
2answers
4k views

Generic Adjacency List Graph implementation

I am trying to come up with a decent Adjacency List graph implementation so I can start tooling around with all kinds of graph problems and algorithms like traveling salesman and other problems... ...
3
votes
3answers
414 views

Data structure: sort and search effectively

I need to have a data structure with say 4 keys . I can sort on any of these keys. What data structure can I opt for? Sorting time should be very little. I thought of a tree, but it will be only help ...
6
votes
3answers
2k views

Data classes: getters and setters or different method design

I've been trying to design an interface for a data class I'm writing. This class stores styles for characters, for example whether the character is bold, italic or underlined. But also the font-size ...
9
votes
5answers
3k views

Configuration data: single-row table vs. name-value-pair table

Let's say you write an application that can be configured by the user. For storing this "configuration data" into a database, two patterns are commonly used. The single-row table CompanyName | ...
0
votes
5answers
895 views

Learning basic algorithms - better C or C++? [closed]

I'm studying fundamental algorithms (quicksort, mergesort, binary trees, etc..) and I'm going to re-code every algorithm by scratch to learn how they work. Should I code them in C or C++? I think with ...
4
votes
3answers
232 views

I want to create an open data format… but I don't really know what that is

I have found a need for a standardization for storage and recording of data relating to diabetes information (I don't think there's any, but I may have missed it). To that end I made this github ...
8
votes
1answer
350 views

Is there any better approach to shortest path finding within a (vehicular) traffic network?

Dear fellow programmers, We're developing software which simulates vehicular traffic. Part of the process called "assignment" is concerned with assigning vehicles to their routes and has to use some ...
8
votes
4answers
2k views

Analyzing Memory Usage: Java vs C++ Negligible?

How does the memory usage of an integer object written in Java compare\contrast with the memory usage of a integer object written in C++? Is the difference negligible? No difference? A big difference? ...
3
votes
2answers
1k views

Amortized Analysis? (Worst-case Performance Guarantees)

What is Amortized Analysis? And how can it help me achieve worst-case performance guarantees in my programs? I was reading that the following techniques can help the programmer achieve Worst-case ...
6
votes
5answers
2k views

What do you call classes without methods?

What do you call classes without methods? For example, class A { public string something; public int a; } Above is a class without any methods. Does this type of class have a special name?
0
votes
1answer
127 views

Converting data-structure in Perl [closed]

A function produces this hash of arrays: 'KEYNAME1' => ARRAY(0x1edeeb0) 0 'val11' 1 'val12' 2 'val13' 'KEYNAME2' => ARRAY(0x1efacb8) 0 'val21' 1 'val22' 2 'val23' ...
1
vote
2answers
373 views

Arrow => in Perl

What does the => mean in Perl? my $CreateArray = [ objectClass => [ "top", "person", "organizationalPerson", "inetOrgPerson" ], cn => "Jane User", uid => "0000001", sn => "User", mail ...
1
vote
1answer
238 views

hash with file instead of array

Is it possible to use hash function but with File instead of Array, and it's gonna be saving the record in a file position and then search will fseek to that position, but I'm not sure how to open a ...
5
votes
1answer
525 views

Nearest color algorithm using Hex Triplet

Following page list colors with names http://en.wikipedia.org/wiki/List_of_colors. For example #5D8AA8 Hex Triplet is "Air Force Blue". This information will be stored in a databse table (tbl_Color ...
3
votes
4answers
395 views

Appropriate data structure for deeply nested data?

I can't figure out what would be an appropriate data structure for my problem. I need to write a script that will count some events. Input is a list of events (thousands of them). Each event is an ...
2
votes
8answers
937 views

Strategy/algorithm to divide pot to chips

I want to split poker pot to chips. Example: Pot = $17.500. I have the endless piles of chips. I have the following types of chips: ChipsTypes = [$1, $5, $10, $25, $100, $500, $1.000, $5.000, ...
6
votes
1answer
3k views

Decision trees vs. Neural Networks

I'm implementing a machine learning structure to try and predict fraud on financial systems like banks, etc... This means that there is a lot of different data that can be used to train the model eg. ...
1
vote
2answers
108 views

Cataloging events, projects and tasks: Is SQL appropriate?

I have this idea for a database: it would hold everything I "need to remember", and allow future coding projects to access the information. These future projects include a day-planner and historical ...
1
vote
5answers
964 views

What Java data structure/design pattern best models this object, considering it would perform these methods?

Methods: 1. getDistance(CityA,CityB) // Returns distance between two cities 2. getCitiesInRadius(CityA,integer) // Returns cities within a given distance of another city 3. ...
5
votes
2answers
711 views

Writing a new programming language - when and how to bootstrap datastructures?

I'm in the process of writing my own programming language which, thus far, has been going great in terms of what I set out to accomplish. However, now, I'd like to bootstrap some pre-existing data ...
34
votes
4answers
4k views

Which algorithms/data structures should I “recognize” and know by name? [closed]

I'd like to consider myself a fairly experienced programmer. I've been programming for over 5 years now. My weak point though is terminology. I'm self-taught, so while I know how to program, I don't ...
6
votes
3answers
475 views

A deque based on binary trees

This is a simple immutable deque based on binary trees. What do you think about it? Does this kind of data structure, or possibly an improvement thereof, seem useful? How could I improve it, ...
5
votes
11answers
5k views

What are some good, simple examples for queues?

I'm teaching CS2 (Java and data structures), and am having some difficulty coming up with good examples to use when teaching queues. The two major applications I use them for are multithreaded message ...
21
votes
4answers
916 views

What is the definition of “Big Data”?

Is there one? All the definitions I can find describe the size, complexity / variety or velocity of the data. Wikipedia's definition is the only one I've found with an actual number Big data ...
2
votes
1answer
215 views

List structures in memory

Could anyone give an overview of how list structures which are composed of a head and a tail which references the rest of the list i.e linked list are represented in memory of the computer? Does the ...
7
votes
4answers
532 views

finding houses within a radius

During an interview I was asked given the following: A real estate application that lists all houses that are currently on the market (i.e., for sale) within a given distance (say for example the user ...