map(redirected from Mean arterial pressure)
Also found in: Dictionary, Thesaurus, Medical, Legal, Financial, Acronyms, Wikipedia.
map,conventionalized representation of spatial phenomena on a plane surface. Unlike photographs, maps are selective and may be prepared to show various quantitative and qualitative facts, including boundaries, physical features, patterns, and distribution. Each point on such a map corresponds to a geographical position in accordance with a definite scalescale,
in cartography, the ratio of the distance between two points on a map to the real distance between the two corresponding points portrayed. The scale may be expressed in three ways: numerically, as a ratio or a fraction, e.g., 1:100,000 or 1-100,000; verbally, e.g.
..... Click the link for more information. and projection (see map projectionmap projection,
transfer of the features of the surface of the earth or another spherical body onto a flat sheet of paper. Only a globe can represent accurately the shape, orientation, and relative area of the earth's surface features; any projection produces distortion with
..... Click the link for more information. ). Maps may also represent such comparative data as industrial power, population density, and birth and death rates. The earliest European printed maps (2d half of the 15th cent.) were made from woodcuts; maps are now reproduced by several processes, including photoengraving, wax engraving, and lithography. See also chartchart,
term referring to maps prepared for marine navigation and for air navigation. All charts show, in some convenient scale, geographic features useful to the navigator, as well as indications of direction, e.g.
..... Click the link for more information. .
Cartography, or mapmaking, antedates even the art of writing. Diagrams of areas familiar to them were made by Marshall Islanders, Eskimo, Native Americans, and many other preliterate peoples. Maps drawn by ancient Babylonians, Egyptians, and Chinese have been found. The oldest known map, now on exhibition in the Semitic Museum of Harvard, is a Babylonian clay tablet dating from c.2500 B.C. Our present system of cartography was established by the Greeks, who remained unexcelled until the 16th cent. Scientific measurements of earth distances by means of meridians and parallels were first made by EratosthenesEratosthenes
, c.275–c.195 B.C., Greek scholar, b. Cyrene. A pupil of Callimachus in Athens, he became (c.240 B.C.) head of the library at Alexandria. Known for his versatility, he wrote poetry and works (most of them lost) on literature, the theater (notably on ancient
..... Click the link for more information. (3d cent. B.C.). Of the ancient scholars, the mathematician and geographer PtolemyPtolemy
(Claudius Ptolemaeus), fl. 2d cent. A.D., celebrated Greco-Egyptian mathematician, astronomer, and geographer. He made his observations in Alexandria and was the last great astronomer of ancient times.
..... Click the link for more information. (2d cent. A.D.), expounded on the principles of cartography; his system was followed for many centuries, although his basic error in underestimating the earth's size was not corrected until the age of Mercator. Only the Mediterranean world was represented with any accuracy in early maps. During the Middle Ages, while European cartographers produced artistic, idealized maps, Arabic mapmakers, notably IdrisiIdrisi
, in full Abu Abdallah Muhammad Ibn Muhammad Ibn Abdallah Ibn Idris Al-Hammudi Al-Hasani Al-Idrisi, b. 1099?, d. after 1154, Arab geographer, b. Ceuta.
..... Click the link for more information. (12th cent.), carried on the work of Ptolemy, and the Chinese produced the first printed maps.
Cartography in the Sixteenth through Eighteenth Centuries
Three major events contributed to the spectacular renaissance of cartography in Europe around 1500—the rediscovery and translation into Latin of Ptolemy's Geographia, the invention of printing and engraving, and the great voyages of discovery. This renaissance was manifested by the work of Gerardus MercatorMercator, Gerardus
, Latin form of Gerhard Kremer
, 1512–94, Flemish geographer, mathematician, and cartographer. He studied in Louvain, where he had a geographical establishment (1534). From 1537 to 1540 he surveyed and mapped Flanders.
..... Click the link for more information. in the first modern world atlas, published in 1570 by Abraham OrteliusOrtelius, Abraham
, 1527–98, Flemish geographer, of German origin. Next to his contemporary Mercator, he is the most renowned of the 16th-century Flemish school of geography.
..... Click the link for more information. , and by the decorative, paintinglike maps of the French Sanson family (17th cent.). Improvements in the methods of surveying and increased emphasis on accuracy led to the noted work in the 18th cent. of the Frenchmen Guillaume DelisleDelisle, Guillaume
, 1675–1726, French geographer and cartographer. His most important work is a world map (1700), as accurate as the data available at that time permitted and the first map on which the errors of Ptolemy were wholly absent.
..... Click the link for more information. and J. B. B. d'AnvilleAnville, Jean Baptiste Bourguignon d'
, 1697–1782, French geographer and cartographer. His maps of ancient geography, characterized by careful, accurate work and based largely on original research, are especially valuable.
..... Click the link for more information. , the founders of modern cartography. After 1750 many European governments undertook the systematic mapping of their countries. The first important national survey was made in France (published 1756), followed by the Ordnance Survey of Great Britain (published 1801) and the topographic survey of Switzerland (organized 1832). In the United States the U.S. Geological SurveyGeological Survey, United States,
bureau organized in 1879 under the Dept. of the Interior to unify and centralize the work already undertaken by separate surveys under Clarence King, F. V. Hayden, George W. Wheeler, and J. W. Powell.
..... Click the link for more information. (established 1879) has mapped much of the country on varying scales.
During the Nineteenth and Twentieth Centuries
During the 19th cent. the demand for national maps was fulfilled, and famous world atlases were published. But with the advent of the 20th cent. the need arose for an international map of the world on a uniform scale. Accordingly, at several meetings of the International Geographical Congress (1891, 1909, 1913), the German Albrecht PenckPenck, Albrecht
, 1858–1945, German geographer and geologist. He was professor at the Univ. of Vienna (1885–1906) and at the Univ. of Berlin (1906–26) and was director (1906–22) of the institutes of oceanography and of geography, Berlin.
..... Click the link for more information. presented and perfected plans for a world map on a scale of 1:1,000,000, to consist of about 1,500 sheets, each covering four degrees of latitude and six degrees of longitude in a modified conic projection. Uniformity of lettering and the use of layer tints to indicate relief were agreed upon. However, only part of the work has been completed. The greatest single contribution to the map of the world was made by the American Geographical Society of New York, which completed (1945) its 107-sheet Map of Hispanic America.
During World Wars I and II the science and art of mapping were greatly advanced. Modern technology, using remote sensing by airborne and satellite radar, as well as devices called multispectral scanners, has made it possible to quickly collect and update information for mapmaking. Computerized geographic information systems, first developed in the 1960s, now are used to link information stored in databases to maps, increasing and varying the amount of information a map can display. Such systems are used to produce maps for business use, law enforcement, natural-disaster prediction, and many other purposes. In recent years the critical cartography movement, led by a group of British scholars, notably the late J. B. Harley, has studied maps as sociopolitical constructs that interpret reality and reflect the historical power structure as well as their makers' ideas about the world.
See T. W. Birch, Maps: Topographical and Statistical (2d ed. 1964); D. Greenhood, Mapping (rev. ed. 1964); F. J. Monkhouse and H. R. Wilkinson, Maps and Diagrams (1971); N. J. W. Thrower, Maps and Man (1972); G. R. Crone, Maps and Their Makers (5th ed. 1978); L. Bagrow and R. A. Skelton, History of Cartography (enl. 2d ed. 1985, repr. 2010); M. Monmonier, How to Lie with Maps (1991); A. H. Robinson et al., Elements of Cartography (6th ed. 1995); J. Black, Maps and Politics (1997); M. H. Edney, Mapping an Empire (1997); J. B. Harley and D. Woodward, ed., History of Cartography (2 vol., 1987–); J. B. Harley, The New Nature of Maps (2001); J. Black, Maps and Politics (2001); S. Schulten, The Geographical Imagination in America, 1880–1950 (2001); P. Whitfield, The Image of the World (upd. ed. 2010); J. Brotton, A History of the World in 12 Maps (2013).
What does it mean when you dream about a map?
Following a map in a dream signifies the dreamer is being guided and led in a direction that will fulfill the person’s needs, as well as provide growth experiences.
map :: (a -> b) -> [a] -> [b] map f  =  map f (x:xs) = f x : map f xs
This can be generalised to types other than lists.
map(1) A set of data that has a corresponding relationship to another set of data.
(2) A list of data or objects as they are currently stored in memory or disk.
(3) To assign a path or drive letter to a disk drive. See drive mapping.
(4) To transfer a set of objects from one place to another. For example, program modules on disk are mapped into memory. A graphic image in memory is mapped onto the video screen.
(5) To translate, or convert, from one format to another. For example, an address is mapped to another address. A logical database structure is mapped to the physical database.
(6) To relate one set of objects with another. For example, a vendor's protocol stack is mapped to the OSI model. An alias is mapped to the true name of the object. See alias.
(7) (MAP) (Manufacturing Automation Protocol) A communications protocol introduced by General Motors in 1982. MAP provides common standards for interconnecting computers and programmable machine tools used in factory automation. At the lowest physical level, it uses the IEEE 802.4 token bus protocol.
MAP is often used in conjunction with TOP, an office protocol developed by Boeing Computer Services. TOP is used in the front office and MAP is used on the factory floor.