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

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1
vote
1answer
135 views

Format text in a generic and reusable way

I would like to write some long text in some structure to allow a set of operations on that text. The question is which structure or format should I use, which suits best the use that I plan to do of ...
1
vote
3answers
1k views

The best way to store dictionary from file

I'm working on a translator in C++. Basically I want to parse the file with translations and store it in my program, so I can perform search through the words and simply access the corresponding word. ...
3
votes
2answers
180 views

Bayes filtering and data storage with expansive data sets

I am looking to write a Bayes filter that will act as an indicator of topic for a number of topics with a variable number of sources. Given a really big number of RSS feeds and here really big might ...
1
vote
1answer
236 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 ...
3
votes
4answers
1k views

Why many programming languages have only 2 data-structures: arrays and hashes?

Many programming languages have only those 2 structures, and even some languages that have more structures still only provide special syntax for those 2; usually, [] and {}. Why is this? Is there ...
3
votes
2answers
421 views

How should I structure a C# application that reads & writes binary data?

I have to read and write binary "chunks" of approximately 1Mb each. The data can come in the form of a stream or a in-memory byte[]. Normally I would use a Struct with a fixed layout, but there are ...
1
vote
3answers
333 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 ...
4
votes
3answers
480 views

How Immutable Sets are Manipulated

When working with an immutable set or map, like the ones found in many functional programming languages, operations that would otherwise modify the container generate a new container instead. I know ...
9
votes
1answer
452 views

Optimal Data Structure for our own API

I'm in the early stages of writing an Emacs major mode for the Stack Exchange network; if you use Emacs regularly, this will benefit you in the end. In order to minimize the number of calls made to ...
2
votes
4answers
305 views

Plugin Architecture: How to Handle Databases and Logging?

I am in the process of designing an architecture for a plugin based application and I have some questions about how to handle database access and logging. The goal of my application is to allow a ...
12
votes
5answers
492 views

Storing in-text metadata in a discrete data structure

I am developing an application which will need to store inline, intext metadata. What I mean by that is the following: let's say we have a long text, and we want to store some metadata connected with ...
3
votes
3answers
275 views

Is it worth to try write foolproof data structures?

The problem We need to store data in a table-like way, but we have very strict space constraints (~1Mb per table of 10k+ rows). We store data like this: ID | reviews | factor | score | interval | ...
5
votes
6answers
2k views

Why is the usage of string keys generally considered to be a bad idea?

This has been bugging me for a while. Most of the time, when it comes to storing data in structures such as hashtables, programmers, books and articles insist that indexing elements in said structures ...
1
vote
1answer
166 views

Storage and naming of log data

I'm in the process of rewriting a small application from console mode to a GUI mode. The input is a file with log data from a measuring device: ... 00029;00044;00076;00044;00021 ...
3
votes
1answer
228 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 = ...
2
votes
1answer
131 views

Applications with duplicate data - keep separate or combine into one set?

We currently have 3 similar, but slightly different applications that use the same data. We load the (same) data into each application that uses it. The applications are similar and use the same ...
6
votes
3answers
2k 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 ...
0
votes
1answer
124 views

overworld vs on-screen 2d tile organization

I am developing a 2d game where the world is made up of tiles. I have an overworld and a "current world": the current world represent the current tiles on screen at any given time, currently this ...
1
vote
1answer
246 views

Database data structures for RESTful api

I am creating a RESTful API. I am struggling to decide on the best way to design my database tables around my resources. Initially, I though a table per resource would be a good way to go, but I'm ...
2
votes
2answers
2k views

Nested Enum type in C++ or C#?

I've come across a recurring issue in a few of my recent projects in which I find myself using enums to represent state, or type, or something else, and I need to check against a few conditions. Some ...
1
vote
1answer
224 views

Marked nodes in Fibonacci heaps

I don't understand why Fibonacci heaps have marked nodes (picture). A node is marked when its child is deleted. Quoting from Wikipedia: "[Keeping degree of each node low] is achieved by the rule that ...
2
votes
1answer
102 views

creating simple states for a stateless input

Given an input device (basically a keyboard) that reports keyup and keydown, how may I most efficiently store and retrieve information about which keys are currently depressed? My first thought was a ...
0
votes
2answers
202 views

Data structure for fast StartsWith filtering of a dictionary

I have a list of english words. I'm trying to come up with a data structure that allows me to do fast StartsWith filtering, like: var words = dictionary.StartsWith("foo"); I was thinking of ...
17
votes
2answers
1k views

What's the difference in content between Chris Okasaki's 1996 thesis and 1999 book, Purely Functional Data Structures?

I want to read Purely Functional Data Structures. I've easily found the thesis (which is freely available as a PDF), but see that there's a book available also. So I'd like to know what the ...
7
votes
4answers
8k views

What is the point of using lists over vectors, in C++?

I've run 3 different experiments involving C++ lists and vectors. Those with vectors proved more efficient, even when a lot of insertions in the middle were involved. Hence the question: in which ...
7
votes
2answers
1k views

Using a stream manipulator (endl) or a newline escape character (\n)?

I don't have a specific context in which I'm asking the question, but while I was reading a beginner book on C++ I noticed the use of both an endl stream manipulator and a newline escape character ...
0
votes
2answers
467 views

Algorithms for data structures in distributed system

The hash table data structure can be easily spread across multiple machines with a simple algorithm to distribute the keys: machine_to_query = item_key % machine_count When you want to read and ...
5
votes
2answers
814 views

How do scalable bloom filters work?

I was reading up on scalable bloom filters and could not understand how each time a constituent bloom filters fills up, a new bloom filter with larger size is added. The elements that contributed to ...
1
vote
2answers
4k views

How to increase the efficiency of an Immutable Queue in java?

I have been developing an Immutable queue in java, but the version I have developed is supposedly slow and I have been suggested to create a faster version of the same and I have no idea as to how to ...
2
votes
2answers
677 views

Thoughts on a custom data structure for a node/chain implementation

I am designing a simple GUI that will allow a user to create a GPX route by clicking repeatedly on a map panel. I am faced with a design dilemma for how to represent the nodes and route. This ...
4
votes
2answers
786 views

Creating huge decision tree

I'm to write an event correlator. A fundamental part of the system will be a decision tree that recognizes the origin of the fault basing on recorded states and log files. Often many accidents will ...
3
votes
6answers
468 views

Should a database table(s) structure match its intended data structure(s) in the logic?

This question branches out of this question, What are the differences between algorithms using data structures and algorithms using databases?. The General Question Should a database table(s) ...
6
votes
4answers
345 views

Representing a rule in a ruleset

How to represent rules for a rule engine as objects? A rule would be if (booleanExpression(input)) then a chain of generic actions" else next rule ...where the generic actions might be e.g. ...
7
votes
4answers
2k views

What are the differences between algorithms using data structures and algorithms using databases?

The General Question What are the differences between algorithms using data structures and algorithms using databases? Some Context This is a question that has been bugging me for some time, and I ...
1
vote
3answers
744 views

What data structure could a word processor use to map the user's caret position/text selection to its internal representation of the document?

Word processors (e.g. Microsoft Word) display documents to the user as styled text. The user can select a part of this text and apply styles to it, and edit the text. The word processor must (I ...
3
votes
1answer
116 views

Representing domain objects

This is related to my recent question regarding naming awkward domain objects. A number of answers indicated I was using the wrong representation for the domain objects. To summarize, I chose to use ...
-1
votes
1answer
634 views

Simple dependency tree diagram generator [closed]

I have a need to produce a simple dependency tree diagram. The input data would be in the following simple format: ITEM_NAME DEPENDENCY ---------------------------- ITEM_101 ITEM_75 ITEM_102 ...
3
votes
2answers
2k views

How, when, and why do developers use custom data structures in python?

Python's lack of pointers makes data-structure construction intuitively more challenging, and has so much built in functionality that, as an amateur, I can't see when, why, or how you would create ...
20
votes
3answers
764 views

How do I express subtle relationships in my data?

"A" is related to "B" and "C". How do I show that "B" and "C" might, by this context, be related as well? Example: Here are a few headlines about a recent Broadway play: David Mamet's Glengarry ...
4
votes
3answers
667 views

Is it conceivable to have millions of lists of data in memory in Python?

I have over the last 30 days been developing a Python application that utilizes a MySQL database of information (specifically about Norwegian addresses) to perform address validation and correction. ...
11
votes
1answer
9k views

Sets Data Structure in Golang

I really like google golang but could some one explain what the rationale is for the implementors having left out a basic data structure such as sets from the standard library?
-3
votes
1answer
620 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
345 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
780 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
408 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
993 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
189 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 ...
4
votes
2answers
767 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
7k 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
281 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 ...