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Geohash
Geohash is a public domain geocode system invented in 2008 by Gustavo NiemeyerEvidences at the Wayback Machine: labix.org in 2008, the G. Niemeyer's blog announcing Geohash *an article about Geohash witnessing and citing G. Niemeyer works, before 2012 G. Niemeyer's post at forums.geocaching.com announcing Geohash in Feb. 2008 which encodes a geographic location into a short string of letters and digits. Similar ideas were introduced by G.M. Morton in 1966.G. M. Morton (196''"A Computer Oriented Geodetic Data Base and a New Technique in File Sequencing"''. Report in IBM Canada. It is a hierarchical spatial data structure which subdivides space into buckets of grid shape, which is one of the many applications of what is known as a Z-order curve, and generally space-filling curves. Geohashes offer properties like arbitrary precision and the possibility of gradually removing characters from the end of the code to reduce its size (and gradually lose precision). Geohashing guarantees th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Geocode
A geocode is a code that represents a geographic entity (location or object). It is a unique identifier of the entity, to distinguish it from others in a finite set of geographic entities. In general the ''geocode'' is a human-readable and short identifier. Typical geocodes and entities represented by it: * ''Country code'' and subdivision code. Polygon of the administrative boundaries of a country or a subdivision. The main examples are ISO codes: ISO 3166-1 alpha-2 code (e.g. AF for Afghanistan or BR for Brazil), and its subdivision conventions, such as subdivision codes (e.g. AF-GHO for Ghor province) or subdivision codes (e.g. BR-AM for Amazonas state). * ''DGG cell ID''. Identifier of a cell of a discrete global grid: a Geohash code (e.g. ~0.023 km2 cell 6vjyngd at the Brazilian's center) or an OLC code (e.g. ~0.004 km2 cell 58PJ642P+4 at the same point). * ''Postal code''. Polygon of a postal area: a CEP code (e.g. 70040 represents a Brazilian ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Base 32
Base32 is the base-32 numeral system. It uses a set of 32 digits, each of which can be represented by 5 bits (25). One way to represent Base32 numbers in a human-readable way is by using a standard 32-character set, such as the twenty-two upper-case letters A–V and the digits 0-9. However, many other variations are used in different contexts. The rest of this article discusses the use of Base32 for representing byte strings, not unsigned integer numbers, similar to the way Base64 works. This is an example of a Base32 representation using the previously described 32-character set ( IPFS CIDv1 in Base32 upper-case encoding): Advantages Base32 has a number of advantages over Base64: # The resulting character set is all one case, which can often be beneficial when using a case-insensitive filesystem, DNS names, spoken language, or human memory. # The result can be used as a file name because it cannot possibly contain the '/' symbol, which is the Unix path separator. # The ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Base32
Base32 is the base-32 numeral system. It uses a set of 32 digits, each of which can be represented by 5 bits (25). One way to represent Base32 numbers in a human-readable way is by using a standard 32-character set, such as the twenty-two upper-case letters A–V and the digits 0-9. However, many other variations are used in different contexts. The rest of this article discusses the use of Base32 for representing byte strings, not unsigned integer numbers, similar to the way Base64 works. This is an example of a Base32 representation using the previously described 32-character set (IPFS CIDv1 in Base32 upper-case encoding): Advantages Base32 has a number of advantages over Base64: # The resulting character set is all one case, which can often be beneficial when using a case-insensitive filesystem, DNS names, spoken language, or human memory. # The result can be used as a file name because it cannot possibly contain the '/' symbol, which is the Unix path separator. # The alp ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Z-order Curve
In mathematical analysis and computer science, functions which are Z-order, Lebesgue curve, Morton space-filling curve, Morton order or Morton code map multidimensional data to one dimension while preserving locality of the data points. It is named in France after Henri Lebesgue, who studied it in 1904, and named in US after Guy Macdonald Morton, who first applied the order to file sequencing in 1966. The z-value of a point in multidimensions is simply calculated by interleaving the binary representations of its coordinate values. Once the data are sorted into this ordering, any one-dimensional data structure can be used such as binary search trees, B-trees, skip lists or (with low significant bits truncated) hash tables. The resulting ordering can equivalently be described as the order one would get from a depth-first traversal of a quadtree or octree. Coordinate values The figure below shows the Z-values for the two dimensional case with integer coordinates 0 ≤&nb ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Space-filling Curves
In mathematical analysis, a space-filling curve is a curve whose range contains the entire 2-dimensional unit square (or more generally an ''n''-dimensional unit hypercube). Because Giuseppe Peano (1858–1932) was the first to discover one, space-filling curves in the 2-dimensional plane are sometimes called ''Peano curves'', but that phrase also refers to the Peano curve, the specific example of a space-filling curve found by Peano. Definition Intuitively, a curve in two or three (or higher) dimensions can be thought of as the path of a continuously moving point. To eliminate the inherent vagueness of this notion, Jordan in 1887 introduced the following rigorous definition, which has since been adopted as the precise description of the notion of a ''curve'': In the most general form, the range of such a function may lie in an arbitrary topological space, but in the most commonly studied cases, the range will lie in a Euclidean space such as the 2-dimensional plane (a ''pl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Geographical Coordinate System
The geographic coordinate system (GCS) is a spherical or ellipsoidal coordinate system for measuring and communicating positions directly on the Earth as latitude and longitude. It is the simplest, oldest and most widely used of the various spatial reference systems that are in use, and forms the basis for most others. Although latitude and longitude form a coordinate tuple like a cartesian coordinate system, the geographic coordinate system is not cartesian because the measurements are angles and are not on a planar surface. A full GCS specification, such as those listed in the EPSG and ISO 19111 standards, also includes a choice of geodetic datum (including an Earth ellipsoid), as different datums will yield different latitude and longitude values for the same location. History The invention of a geographic coordinate system is generally credited to Eratosthenes of Cyrene, who composed his now-lost ''Geography'' at the Library of Alexandria in the 3rd century ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Geotagging
Geotagging, or GeoTagging, is the process of adding geographical identification metadata to various media such as a geotagged photograph or video, websites, SMS messages, QR Codes or RSS feeds and is a form of geospatial metadata. This data usually consists of latitude and longitude coordinates, though they can also include altitude, bearing, distance, accuracy data, and place names, and perhaps a time stamp. Geotagging can help users find a wide variety of location-specific information from a device. For instance, someone can find images taken near a given location by entering latitude and longitude coordinates into a suitable image search engine. Geotagging-enabled information services can also potentially be used to find location-based news, websites, or other resources. Geotagging can tell users the location of the content of a given picture or other media or the point of view, and conversely on some media platforms show media relevant to a given location. The geograp ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Latitude And Longitude
The geographic coordinate system (GCS) is a spherical or ellipsoidal coordinate system for measuring and communicating positions directly on the Earth as latitude and longitude. It is the simplest, oldest and most widely used of the various spatial reference systems that are in use, and forms the basis for most others. Although latitude and longitude form a coordinate tuple like a cartesian coordinate system, the geographic coordinate system is not cartesian because the measurements are angles and are not on a planar surface. A full GCS specification, such as those listed in the EPSG and ISO 19111 standards, also includes a choice of geodetic datum (including an Earth ellipsoid), as different datums will yield different latitude and longitude values for the same location. History The invention of a geographic coordinate system is generally credited to Eratosthenes of Cyrene, who composed his now-lost ''Geography'' at the Library of Alexandria in the 3rd century BC. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Edge Case
An edge case is a problem or situation that occurs only at an extreme (maximum or minimum) operating parameter. For example, a stereo speaker might noticeably distort audio when played at maximum volume, even in the absence of any other extreme setting or condition. An edge case can be expected or unexpected. In engineering, the process of planning for and gracefully addressing edge cases can be a significant task, and yet this task may be overlooked or underestimated. Non-trivial edge cases can result in the failure of an object that is being engineered. They may not have been foreseen during the design phase, and they may not have been thought possible during normal use of the object. For this reason, attempts to formalize good engineering standards often include information about edge cases. Software engineering In programming, an edge case typically involves input values that require special handling in an algorithm behind a computer program. As a measure for validating th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Textual Representation
In literary theory, textuality comprises all of the attributes that distinguish the communicative content under analysis as an object of study. It is associated with structuralism and post-structuralism. Explanation Textuality is not just about the written word; it also comprises the placement of the words and the reader’s interpretation. There is not a set formula to describe a text’s textuality; it is not a simple procedure. This summary is true even though the interpretation that a reader develops from that text may decide the identity and the definitive meanings of that text. Textuality, as a literary theory, is that which constitutes a text in a particular way. The text is an undecidable (there is an inexistence of an effective or "strict" method of writing or structure). Aspects Being textual includes innumerable elements and aspects. Each and every form of text and text in that form of literature embraces and consists of its own individual and personal characteris ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Jutland, Denmark
Jutland ( da, Jylland ; german: Jütland ; ang, Ēota land ), known anciently as the Cimbric or Cimbrian Peninsula ( la, Cimbricus Chersonesus; da, den Kimbriske Halvø, links=no or ; german: Kimbrische Halbinsel, links=no), is a peninsula of Northern Europe that forms the continental portion of Denmark and part of northern Germany. The names are derived from the Jutes and the Cimbri, respectively. As with the rest of Denmark, Jutland's terrain is flat, with a slightly elevated ridge down the central parts and relatively hilly terrains in the east. West Jutland is characterised by open lands, heaths, plains, and peat bogs, while East Jutland is more fertile with lakes and lush forests. Southwest Jutland is characterised by the Wadden Sea, a large unique international coastal region stretching through Denmark, Germany, and the Netherlands. Geography Jutland is a peninsula bounded by the North Sea to the west, the Skagerrak to the north, the Kattegat and Baltic Sea to the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
