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

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41
votes
6answers
4k views

How necessary is it to follow defensive programming practices for code that will never be made publicly available?

I'm writing a Java implementation of a card game, so I created a special type of Collection I'm calling a Zone. All modification methods of Java's Collection are unsupported, but there's a method in ...
0
votes
2answers
265 views

Most efficient data structure for implementing inheritance structure without classes

I have a number of types that all relate to each other in terms of them being 'derived' from one another. I'd need a way to do is relationships, which made me initially think of classes, but I ...
3
votes
4answers
311 views

fast n-gram access data structure

TL;DR Is there a data structure that'd quickly let me match words at any point (e.g., 'foo' matches 'foobar' and 'zoofoo'), and, ideally, returns a list of "characters that show up after the needle" ...
4
votes
1answer
225 views

Designing storage service data structure for decoupled models sharing same data

Surely most of you remember the Norton Commander application where similar (sometimes the same) data is displayed in separate decoupled views. I'm building a web application that follows the same ...
0
votes
1answer
71 views

What is the difference between a Splay Tree and an Optimal Binary Search Tree?

Both these trees try to keep the most frequently accessed element at the top. Is there any difference between these two trees?
1
vote
2answers
174 views

Minimize touching the already-working code when a radical change is required

I have a code that highly relies on an Array structure like the following: $array['customer'][$customer_id]['details'][..]; // it goes to about 10 levels deep However, after almost two years ...
3
votes
1answer
297 views

How do I transparently cache data in intermediate stages of processing?

I am working with MATLAB on a model reduction algorithm. It is basically a data processing pipeline. ckt = generate_ckt(ckt_properties); freq = generate_fpoints(fconfig); result = ...
17
votes
3answers
1k views

How do purely functional programming languages deal with fast changing data?

What data structures can you use so you can get O(1) removal and replacement? Or how can you avoid situations when you need said structures?
0
votes
1answer
72 views

Method to store some site content data, allowing reusability

(Don't believe this is a "best practice" question as I believe there will be a single better choice). I need to choose a data storage option to store specific site data to allow easy management and ...
1
vote
2answers
243 views

Data retrieval and indexing

I have around 800,000 rows of data stored in the boost shared memory from the database. The data are in the form: Id Color Length Size 1 1 2 ...
0
votes
2answers
240 views

Data structure theory based on graph rewriting [closed]

First of all, I'm looking for a book, publication, project or any kind of information that should probably exceed the limits normally imposed on answers in this kind of forum. I know the rules about ...
4
votes
5answers
470 views

Is my understanding of abstract datatypes correct?

After reading lots of pages on various sites, I came to the conclusion that abstract datatype helps to separate the use of datastructure from its implementation. We can easily map the data into a ...
1
vote
1answer
304 views

Is there already a “Binder” data-structure?

I was thinking of a data structure that I cannot describe better than with the word "book", or more exactly "binder". I was wondering if this had already been implemented in libraries like Boost or ...
1
vote
2answers
487 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
343 views

Handling timeout in network application

How can I handle timeouts in a network application. I'm implementing a provisioning system on a Linux server, the code is huge so I'm going to put the algorithm, it works as like this Read ...
1
vote
1answer
110 views

Implementation/Representation of Symmetries in Chessboards

In a 8X8 chessboard, I was wondering how to implement the symmetry of the board. A lot of positions are just mirrors or rotations of one another (with no pawns or castling capabilities left the ...
1
vote
2answers
184 views

Documenting/defining data structures in Python

What is the preferred way to document the contents of and logic behind dynamically generated data structures in Python? E.g. a dict which contains the mapping of a string to a list of lists of ...
0
votes
3answers
924 views

Collection providing lookup by one of several keys [closed]

What do you call a collection in which each item may be looked up by one of multiple keys? A partial, simplified definition in C# might be: class MyDataStructure<TKey1, TKey2, TValue> { ...
2
votes
2answers
169 views

Replacing static classes with global state to a series of POJOs, beginning to feel like an anti-pattern

I'm trying to refactor some code, and one of the major changes is to remove the (ab)use of static classes to give global state. I've tried to split up some of the 'global state' functionality with ...
5
votes
1answer
133 views

Bloom filters or similar, but with no false positive

To improve some lookups, I am considering the use of Bloom Filters. But in my use-case, the most probable outcome is that the element do exists in the target set. Bloom filters can have false ...
4
votes
2answers
403 views

Is there any particular reason for the use of lists over queues in functional programming languages?

Most functional programming languages such as Scheme and Haskell use lists as their main data structure. Queues are identical to lists, except for the fact appending to the end - not to the begin - ...
4
votes
2answers
894 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 ...
1
vote
0answers
47 views

Compound container for storing output from a parser

Consider a hierarchical structure like this directory [ [item_0;item_1;...;item_n] [item_0;item_1;inner_directory[...];item_m] other_directory [...] ] ...
0
votes
2answers
250 views

Critique the Structure of my Horse Racing Betting Platform

I am creating a program (mostly just for fun) that displays live prices for horse racing markets and the prices that several models predict they should be. I am very interested in the optimal way to ...
0
votes
1answer
274 views

Is there any practical algorithm / data-structure that can't be done with non-recursive Lambda Calculus augmented with foldl?

In my search for a practical non-turing complete programming language, I've been paying attention to lambda-calculus with disallowed self-application - that is, x x forbidden. After taking that ...
1
vote
3answers
369 views

What can Go chan do that a list cannot?

I want to know in which situation Go chan makes code much simpler than using list or queue or array that is usually available in all languages. As it was stated by Rob Pike in one of his speeches ...
0
votes
0answers
43 views

Designing online exam [duplicate]

I need to design an online exam server for an exam like GRE in which question difficulty increases if you answer correctly and decreases if you answer wrong. Questions are multiple choice ...
0
votes
1answer
219 views

Designing online exam

I need to design an online exam server for an exam like GRE in which question difficulty increases if you answer correctly and decreases if you answer wrong. Questions are multiple choice ...
2
votes
3answers
257 views

Why it is `(cons 1 (cons 2 (cons 3 nil)))` and not `(cons 3 (cons 2 (cons 1 nil)))` for [1,2,3]?

Is there any special reason that to construct list in Scheme you use (cons 1 (cons 2 (cons 3 nil))) instead of (cons 3 (cons 2 (cons 1 nil))) ? While the first seems more obvious because it ...
1
vote
2answers
170 views

Random access (read/write) in datastructures

Certain datastructures, like Python's Dictionary, are unordered/random read/written. As programming in python is iterative (and programming in general is?), how do these unordered datastructures ...
1
vote
0answers
194 views

Most suitable data structure for in-memory string -> int conversion for variable length strings

My project involves validating and normalising email addresses in this format [userpart]@[domainpart].[tld] After syntactic validation of the address, [tld] is checked to exist, otherwise the ...
7
votes
4answers
862 views

How do we keep dependent data structures up to date?

Suppose you have a parse tree, an abstract syntax tree, and a control flow graph, each one logically derived from the one before. In principle it is easy to construct each graph given the parse tree, ...
0
votes
2answers
398 views

PHP SplFixedArray How To Deal With billions of indexes?

I've built a flatfile db system that will work like mini-noSQL system and it split db to smaller files, and I did a SplFixedArray wrapper for it with a method for searching usage built on preg_grep. ...
0
votes
1answer
216 views

Which data structure for representing possible navigations between a game's screens?

I am trying to find an appropriate data structure for representing available navigations between a game's screens. Using a linked list, a node can only have one node after it : inappropriate. Using ...
5
votes
1answer
281 views

Can anyone explain to me what problem Core Data solves? [closed]

Core Data seems to add a needless layer of complexity. If you want to save data created natively by the user in an app why not just use an object and then write the data all to SQLite or back to a ...
1
vote
1answer
81 views

Data structure supporting the following operations

I'm looking for a data structure for working with a set of data which is most efficient to do the following : Check whether an item has been categorized or not. (The categorized and uncategorized ...
-2
votes
3answers
161 views

what would be the best data structure for my situation [closed]

I have a list of unique string. I don't want to destroy this string i need it.I only need to find out weather an given string S exist in this unique list.What would be the best data structure for this ...
0
votes
2answers
139 views

How should I structure my database to gain maximum efficiently in this scenario?

I'm developing a PHP script that analyzes the web traffic of my clients websites. By placing a link to a javascript on the clients website (think of Google Analyses), my script harvests information ...
6
votes
3answers
3k views

What is the best way to store a table in C++

I'm programming a decision tree in C++ using a slightly modified version of the C4.5 algorithm. Each node represents an attribute or a column of your data set and it has a children per possible value ...
2
votes
2answers
4k views

Is it wise to store a big lump of json on a database row

I have this project which stores product details from amazon into the database. Just to give you an idea on how big it is: [{"title":"Genetic Engineering (Opposing ...
0
votes
1answer
1k views

I need to create an employee schedule/appointments program, but I don't know how to set it up [closed]

I work for a gym. I am the programmer, its just me, nobody else! Gets really frustrating when there's nobody to bounce conceptual ideas off of. I'm getting rid of our archaic paper binder systems for ...
0
votes
4answers
133 views

Data Structure for Small Number of Agents in a Relatively Big 2D World

I'm working on a project where we will implement a kind of world simulation where there is a square 2D world. Agents live on this world and make decisions like moving or replicating themselves based ...
1
vote
6answers
6k 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 ...
3
votes
2answers
134 views

Reconstructing a tree from depth information

I have a data structure that describes a tree. Nodes are ordered, with "depth" information, and knowing the order and the depth the tree can be reconstructed. I'm not entirely sure how to describe it ...
3
votes
1answer
923 views

Implementing basic data structures in programming interviews [closed]

I have been preparing to do my first technical interview in a month, and I have a question about implementing common data structures like stacks or linked lists. I plan to do the interview in either ...
4
votes
1answer
2k views

Treating a 1D data structure as 2D grid

Hopefully this is a good question. I am working with a native class that represents a 2D image as a 1D array. If you want to change one pixel, for example, you need to now how to derive the index from ...
-1
votes
3answers
3k views

Why are algorithms and data structures important? [duplicate]

It seems like a lot of university-level computer science programs and programmer job interviews focus heavily on algorithms and data structures. I'm curious as to why universities and employers put so ...
-1
votes
2answers
533 views

Importance of data structures in modern S/W development [closed]

During 1990s when there were no advanced frameworks/paradigms available for S/W development , knowledge on data structures was critical... which I can comprehend. But nowadays, for most of the ...
1
vote
1answer
232 views

Inventory / Stock in multiple locations

I am working on a warehouse management system (WMS) that needs to support having stock in multiple locations. Could be in a different building, could be stored in n* places in a building (quick ...
1
vote
1answer
360 views

Immutable Data Structure For Time Series Data

I'm wondering what the best data structure (for storing data on disk) is for storing immutable time-series data (99% of the data is truly immutable, the 1% is metadata that is separate from the ...