Questions tagged [data]

Data are values of qualitative or quantitative variables, belonging to a set of items. Data in computing (or data processing) are represented in a structure, often tabular (represented by rows and columns), a tree (a set of nodes with parent-children relationship) or a graph structure (a set of interconnected nodes).

Data are values of qualitative or quantitative variables, belonging to a set of items. Data in computing (or data processing) are represented in a structure, often tabular (represented by rows and columns), a tree (a set of nodes with parent-children relationship) or a graph structure (a set of interconnected nodes). Data are typically the results of measurements and can be visualised using graphs or images. Data as an abstract concept can be viewed as the lowest level of abstraction from which information and then knowledge are derived. Raw data, i.e., unprocessed data, refers to a collection of numbers, characters and is a relative term; data processing commonly occurs by stages, and the "processed data" from one stage may be considered the "raw data" of the next. Field data refers to raw data collected in an uncontrolled in situ environment. Experimental data refers to data generated within the context of a scientific investigation by observation and recording.

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Should temporary files be saved to /tmp or the current working directory?

I have a program that needs to generate temporary files. It is written for cluster machines. If I saved those files to a system-wide temporary directory (eg: /tmp), some users complained the program failed because they didn't have proper access to…
ABCD
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Are data type declarators like "int" and "char" stored in RAM when a C program executes?

When a C program is running, the data is stored on the heap or the stack. The values are stored in RAM addresses. But what about the type indicators (e.g., int or char)? Are they also stored? Consider the following code: char a = 'A'; int x = 4; I…
user16307
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Should test data be checked into version control?

I'm writing some test code for a feature which processes PDF files. The basic idea behind the tests is that I point them towards some PDFs I've selected specially, they process them and I check that the output is what I expect. My question is:…
Swiftheart
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Data Synchronization in mobile apps - multiple devices, multiple users

I'm looking into building my first mobile app. One of the core features of the application is that multiple devices/users will have access to the same data -- and all of them will have CRUD rights. I believe the architecture should involve a central…
ProgrammerNewbie
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Why the static data members have to be defined outside the class separately in C++ (unlike Java)?

class A { static int foo () {} // ok static int x; // <--- needed to be defined separately in .cpp file }; I don't see a need of having A::x defined separately in a .cpp file (or same file for templates). Why can't be A::x declared and defined…
iammilind
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Is there an alternative to bits?

Is there an alternative to bits as the smallest unit of data? Something that won't be only 0 or 1, but actually hold many possible states in between? Wouldn't it be more natural to store floats like that?
Dokkat
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Modeling first and lastname separately

Which arguments should someone consider when designing a new system and has to either store the name of a person as one field or separately as first/last name? Pros for single field: Simpler UI No ambiguity when trying to enter the name of a…
Istvan Devai
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Does storing plain text data take up less space than storing the equivalent message in binary?

As a web developer I have very little understanding of binary data. If I take the sentence "Hello world.", convert it to binary, and store it as binary in an SQL database, it seems like the 1s and 0s would take up more space than the letters. It…
john doe
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Would having 4 states per "bit" rather than 2 mean twice the storage space?

Pretty straightforward fundamental, albeit naive, question: Would having 4 states per "bit" rather than 2 mean twice the storage space? In case that isn't clear, I mean as in if every "storage structure", rather than only representing 2 values,…
J.Todd
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Is there a list of common usernames to reserve in a new system?

I need to reserve usernames in my new website. These generally fall into three categories 1) usernames no-one should have (eg: admin, user, service, help, root, etc) 2) names of super famous people or companies we may want to reserve in the event…
mattx
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Data input validation - Where? How much?

Data input validation always was quite an internal struggle to me. On the verge of adding a real security framework and code to our legacy application rewrite project (which so far pretty much keeps the card-castle-strong legacy security code and…
mdrg
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Why does Garbage Collection only sweep the heap?

Basically, I've learned so far that garbage collection erases forever any data structure that is not currently being pointed to. But this only checks the heap for such conditions. Why doesn't it also check the data section (globals, constants, etc…
Dark Templar
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Professional way to produce a large problem without filling up huge arrays: C++, free memory from part of an array

I'm developing a physics simulation, and as I'm rather new to programming, I keep running into problems when producing large programs (memory issues mainly). I know about dynamic memory allocation and deletion (new / delete, etc), but I need a…
Drummermean
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Data validation: separated class or not?

When I have a lot of data that needs to be validated, should I create a new class for the sole purpose of validation or should I stick with in-method validation? My particular example contemplates a tournament and a event/category class: Tournament…
dabadaba
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How should HTML data formats be applied in everyday situations?

Given Google's shift towards a stronger focus on page markup data, how do the data formats used in Schema.org work alongside those for Microformats? How do these (and other specs) compliment each other and which should be used in preference in…
Phil.Wheeler
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