Wednesday 8 November 2017

Table

table is an arrangement of data in rows and columns, or possibly in a more complex structure. Tables are widely used in communicationresearch, and data analysis. Tables appear in print media, handwritten notes, computer software, architectural ornamentation, traffic signs, and many other places. The precise conventions and terminology for describing tables vary depending on the context. Further, tables differ significantly in variety, structure, flexibility, notation, representation and use.[1][2][3][4][5] In books and technical articles, tables are typically presented apart from the main text in numbered and captioned floating blocks.

Basic description[edit]

A table consists of an ordered arrangement of rows and columns. This is a simplified description of the most basic kind of table. Certain considerations follow from this simplified description:
  • the term row has several common synonyms (e.g., record, k-tuple, n-tuple, vector);
  • the term column has several common synonyms (e.g., field, parameter, property, attribute);
  • a column is usually identified by a name;
  • a column name can consist of a word, phrase or a numerical index;
  • the intersection of a row and a column is a cell.
The elements of a table may be grouped, segmented, or arranged in many different ways, and even nested recursively. Additionally, a table may include metadataannotations, a header,[6] a footer or other ancillary features.[5]

Simple table[edit]

The following illustrates a simple table with three columns and seven rows. The first row is not counted, because it is only used to display the column names. This is called a "header row".
Age table
First nameLast nameAge
TinuElejogun14
BlaszczykKostrzewski25
LilyMcGarrett16
OlatunkboChijiaku22
AdrienneAnthoula22
AxeliaAthanasios22
Jon-KabatZinn22
ThabangMosoa15
KgaogeloMosoa11

Multi-dimensional table[edit]

An example of a table containing rows with summary information. The summary information consists of subtotals that are combined from previous rows within the same column.
The concept of dimension is also a part of basic terminology.[7] Any "simple" table can be represented as a "multi-dimensional" table by normalizing the data values into ordered hierarchies. A common example of such a table is a multiplication table.
Multiplication table
×123
1123
2246
3369
In multi-dimensional tables, each cell in the body of the table (and the value of that cell) relates to the values at the beginnings of the column (i.e. the header), the row, and other structures in more complex tables. This is an injective relation: each combination of the values of the headers row (row 0, for lack of a better term) and the headers column (column 0 for lack of a better term) is related to a unique cell in the table:
  • Column 1 and row 1 will only correspond to cell (1,1);
  • Column 1 and row 2 will only correspond to cell (2,1) etc.

Wide and Narrow Tables[edit]

Tables can be described as wide or narrow in format.

Generic representation[edit]

As a communication tool, a table allows a form of generalization of information from an unlimited number of different social or scientific contexts. It provides a familiar way to convey information that might otherwise not be obvious or readily understood.
For example, in the following diagram, two alternate representations of the same information are presented side by side. On the left is the NFPA 704 standard "fire diamond" with example values indicated and on the right is a simple table displaying the same values, along with additional information. Both representations convey essentially the same information, but the tabular representation is arguably more comprehensible to someone who is not familiar with the NFPA 704 standard. The tabular representation may not, however, be ideal for every circumstance (for example because of space limitations, or safety reasons).
Fire diamond
Standard RepresentationTabular Representation
Flammability code 2: Must be moderately heated or exposed to relatively high ambient temperature before ignition can occur. Flash point between 38 and 93 °C (100 and 200 °F). E.g., diesel fuelHealth code 3: Short exposure could cause serious temporary or residual injury. E.g., chlorine gasReactivity code 1: Normally stable, but can become unstable at elevated temperatures and pressures. E.g., calciumSpecial hazards (white): no codeNFPA 704 four-colored diamond
2
3
1
Risk levels of hazardous materials in this facility
Health RiskFlammabilityReactivitySpecial
Level 3Level 2Level 1

Specific uses[edit]

There are several specific situations in which tables are routinely used as a matter of custom or formal convention.

Publishing[edit]

Mathematics[edit]

Natural sciences[edit]

Information technology[edit]

Software applications[edit]

Modern software applications give users the ability to generate, format, and edit tables and tabular data for a wide variety of uses, for example:

Software development[edit]

Tables have uses in software development for both high-level specification and low-level implementation. Usage in software specification can encompass ad hoc inclusion of simple decision tables in textual documents through to the use of tabular specification methodologies, examples of which include SCR[8] and Statestep.[9] Proponents of tabular techniques, among whom David Parnas is prominent, emphasize their understandability, as well as the quality and cost advantages of a format allowing systematic inspection,[10]while corresponding shortcomings experienced with a graphical notation were cited in motivating the development of at least two tabular approaches.[9][11]
At a programming level, software may be implemented using constructs generally represented or understood as tabular, whether to store data (perhaps to memoize earlier results), for example, in arrays or hash tables, or control tables determining the flow of program execution in response to various events or inputs.

Databases[edit]

Database systems often store data in structures called tables; in which columns are data fields and rows represent data records.

Historical relationship to furniture[edit]

In medieval counting houses, the tables were covered with a piece of checkered cloth, to count money. Exchequer is an archaic term for the English institution which accounted for money owed to the monarch. Thus the checkerboard tables of stacks of coins are a concrete realization of this information.

See also[edit]

References[edit]

  1. Jump up^ Fink, Arlene (2005). How to Conduct Surveys. Thousand Oaks: Sage Publications. ISBN 1-4129-1423-X.
  2. Jump up^ McNabb, David (2002). Research Methods in Public Administration and Nonprofit Management. Armonk: M.E. Sharpe. ISBN 0-7656-0957-6.
  3. Jump up^ Morgan, George (2004). Spss for Introductory Statistics. Hillsdale: Lawrence Erlbaum. ISBN 0-8058-4789-8.
  4. Jump up^ Robey, David (2000). Sound and Structure in the Divine Comedy. Oxford Oxfordshire: Oxford University Press. ISBN 0-19-818498-0.
  5. Jump up to:a b Zielinski, Krzysztof (2006). Software Engineering: Evolution and Emerging Technologies. Amsterdam: IOS Press. ISBN 1-58603-559-2.
  6. Jump up^ see e.g., Page header or Header (computing)
  7. Jump up^ The concept of "dimension" is often applied to tables in different contexts and with different meanings. For example, what is described as a "Simple Table" in this article is alternatively described as a "two dimensional array". This is distinct from "multi-dimensional table" as presented in this article.
  8. Jump up^ Heitmeyer, Constance L. (2002). "Software Cost Reduction". Washington D.C.: Naval Research Laboratory
  9. Jump up to:a b Breen, Michael (2005). "Experience of using a lightweight formal specification method for a commercial embedded system product line" (PDF)Requirements Engineering Journal10 (2): 161–172. doi:10.1007/s00766-004-0209-1
  10. Jump up^ Janicki, Ryszard; Parnas, David Lorge; Zucker, Jeffery (1997). "Tabular representations in relational documents". In Brink, C.; Kahl, W.; Schmidt, G. Relational Methods in Computer Science. Springer Verlag. ISBN 3-211-82971-7
  11. Jump up^ Leveson, Nancy G.; Heimdahl, Mats P. E.; Reese, Jon Damon (1999). "Designing Specification Languages for Process-Control Systems: Lessons Learned and Steps to the Future". Seventh ACM SIGSOFT Symposium on the Foundations on Software Engineering (PDF)doi:10.1145/318773.318937

External links[edit]

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