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The word '''map''' could refer to:
The word '''map''' could refer to:


* In mathematics generally, any function from one set to another. See [https://en.wikipedia.org/wiki/Map_(mathematics) Wikipedia]
* In general mathematics, a "map" is any function from one set to another. For more information, see [[Wikipedia: Map (mathematics)]].


* In [[regular temperament theory]], at least on this wiki, the term "map" is often used to refer in particular to a linear map, such as a tuning map, a projection map, or [[Temperament mapping matrix]]. There are often some implicit restrictions - the term "mapping matrix" often assumes that we are mapping from JI to tempered intervals, for instance, which means that in the standard unweighted basis the entries are all integers. A mapping matrix with one row is called a [[val]].
* In [[regular temperament theory]], the term "map" is used in the more specific sense of a [[Wikipedia:Linear_map|''linear'' map]], which, informally, can be thought of as a function that can be represented by a matrix. Examples include [[tuning map]]s, [[projection matrix|projection map]]s (sometimes called projection matrices), and [[temperament mapping matrix|temperament map]]s (usually called "temperament mapping matrices", or "mapping matrices" or even just "mappings" for short). In the past, the terms "M-map"  and "V-map" were also sometimes used to refer to temperament mappings and [[subgroup basis matrices]], although the terminology has since changed on this wiki. A rank-1 temperament mapping is also called a [[val]].


* In the past, the terms [[M-map]] and [[V-map]] were sometimes used to refer to [[Temperament mapping matrices and [[Subgroup basis matrices]], as the former is a "map on monzos" and the latter a "map on vals" - the latter being an idea introduced later for subgroup calculations, which send vals to subgroup vals (or svals), but the terminology has since changed on this Wiki.
* [[Douglas Blumeyer]] and [[Dave Keenan]] recommend reserving the word "map" for a mapping with one row, so that all maps are mappings but not all mappings are maps; a simple tip to remember this usage is that the shorter word refers to the simpler object. In all occurrences at present on this wiki, as well as in Graham Breed's temperament finder, the term "map" (and not "mapping") consistently refers to a single-row mapping, so following this suggestion would be seamless moving forward. A "tuning map", which maps from generators to cents, is a map in "tuning space"; by analogy, a val is a map in "temperament space", and so it would be perfectly consistent with existing terminology to refer to a val as a "temperament map" as opposed to a "temperament mapping", and then when it is clear from the context that it is a ''temperament'' map, the qualifier "temperament" can be dropped, as is done with "temperament mapping matrix" being abbreviated to "mapping matrix". So the suggestion is equivalent to unqualified occurrences of "map" being assumed to be temperament maps, or in other words, synonymous with vals (except for the integer entry requirement), not tuning maps. Dave and Douglas recommend using "map" rather than "val", for two reasons. First, "map" is a basic linear algebra term with wide familiarity (being specialized for this purpose) while "val" is unnecessary jargon that creates a barrier to understanding by newcomers. Second, the coinage of "val" from the obscure mathematical term "valuation" is tenuous and unlikely to provide helpful insight: "p-adic valuation" is an obscure term for "prime count", which would be an element of a prime-count vector ("monzo"), not a map ("val").


* In the writings of Douglas Blumeyer and Dave Keenan, the term "map" is primarily used in a much more specific sense as a synonym for a val, meaning a mapping matrix with one row and integer entries. In this terminological system, the term "mapping" is instead used in the broader sense to refer to temperament mapping matrices. In this usage, all "maps" are "mappings" but not all "mappings" are "maps" in this sense. The term "map" is also sometimes used to refer to things like tuning maps as well, which do not have integer coefficients. Thus, in this usage, we can identify it with a [[Wikipedia:Linear_form|linear form]], which is a function that can be represented by a [[Wikipedia:Covector|covector]], whereas in the broader usage within RTT we can identify it with a [[Wikipedia:Linear_map|linear map]]. A simple tip to remember the difference between "map" and "mapping" in this usage is that the shorter word refers to the simpler object.
{{Disambiguation}}


[[Category:Temperament]]
[[Category:Regular temperament theory]]
[[Category:Regular temperament theory]]
[[Category:Theory]]
[[Category:Terms]]
[[Category:Terms]]
[[Category:Math]]
[[Category:Math]]
[[Category:Val]]
[[Category:Val]]
[[Category:Mapping]]
[[Category:Mapping]]
[[Category:Tuning]]

Latest revision as of 06:39, 26 July 2023

The word map could refer to:

  • In regular temperament theory, the term "map" is used in the more specific sense of a linear map, which, informally, can be thought of as a function that can be represented by a matrix. Examples include tuning maps, projection maps (sometimes called projection matrices), and temperament maps (usually called "temperament mapping matrices", or "mapping matrices" or even just "mappings" for short). In the past, the terms "M-map" and "V-map" were also sometimes used to refer to temperament mappings and subgroup basis matrices, although the terminology has since changed on this wiki. A rank-1 temperament mapping is also called a val.
  • Douglas Blumeyer and Dave Keenan recommend reserving the word "map" for a mapping with one row, so that all maps are mappings but not all mappings are maps; a simple tip to remember this usage is that the shorter word refers to the simpler object. In all occurrences at present on this wiki, as well as in Graham Breed's temperament finder, the term "map" (and not "mapping") consistently refers to a single-row mapping, so following this suggestion would be seamless moving forward. A "tuning map", which maps from generators to cents, is a map in "tuning space"; by analogy, a val is a map in "temperament space", and so it would be perfectly consistent with existing terminology to refer to a val as a "temperament map" as opposed to a "temperament mapping", and then when it is clear from the context that it is a temperament map, the qualifier "temperament" can be dropped, as is done with "temperament mapping matrix" being abbreviated to "mapping matrix". So the suggestion is equivalent to unqualified occurrences of "map" being assumed to be temperament maps, or in other words, synonymous with vals (except for the integer entry requirement), not tuning maps. Dave and Douglas recommend using "map" rather than "val", for two reasons. First, "map" is a basic linear algebra term with wide familiarity (being specialized for this purpose) while "val" is unnecessary jargon that creates a barrier to understanding by newcomers. Second, the coinage of "val" from the obscure mathematical term "valuation" is tenuous and unlikely to provide helpful insight: "p-adic valuation" is an obscure term for "prime count", which would be an element of a prime-count vector ("monzo"), not a map ("val").
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