Monday 11 August 2014

Numeral system

From Wikipedia, the free reference book

This article is about diverse techniques for communicating numbers with images. For the order of numbers in math, see Number. For how numbers are communicated utilizing words, see Numeral (etymology).

This article incorporates an arrangement of references, however its sources stay hazy on the grounds that it has lacking inline references. It would be ideal if you help to enhance this article by presenting more exact references. (January 2011)

Numeral frameworks

by society

Hindu–arabic birthplaces

Indian Bengali Tamil Telugu

Eastern Arabic Western Arabic

Burmese Khmer Lao Mongolian

Sinhala Thai

East Asian

Chinese Suzhou Japanese Korean Vietnamese

Tallying poles

Alphabetic

Abjad Armenian Āryabhaṭa Cyrillic

Ge'ez Georgian Greek Hebrew Roman

Previous

Aegean Attic Babylonian Brahmi

Egyptian Etruscan Inuit Kharosthi

Mayan Quipu

Ancient

Positional frameworks by base

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 20 24 26 27 32 36 60

Non-standard positional frameworks

Arrangement of numeral frameworks

v t e

A numeral framework (or arrangement of numeration) is a written work framework for communicating numbers, that is, a numerical documentation for speaking to amounts of a given set, utilizing digits or different images as a part of a reliable way. It might be seen as the setting that permits the images "11" to be deciphered as the double image for three, the decimal image for eleven, or an image for different numbers in diverse bases.

Preferably, a numeral framework will:

Speak to a valuable set of numbers (e.g. all whole numbers, or normal numbers)

Give each number spoke to a novel representation (or in any event a standard representation)

Reflect the logarithmic and number-crunching structure of the numbers.

For instance, the normal decimal representation of entire numbers gives each non zero entire number an extraordinary representation as a limited grouping of digits, starting by a non-zero digit. Then again, when decimal representation is utilized for the judicious or genuine numbers, such numbers as a rule have an unbounded number of representations, for instance 2.31 can additionally be composed as 2.310, 2.3100000, 2.309999999..., and so forth., all of which have the same significance with the exception of some logical and different settings where more noteworthy exactness is intimated by a bigger number of figures demonstrated.

Numeral frameworks are in some cases called number frameworks, yet that name is questionable, as it could allude to diverse frameworks of numbers, for example, the arrangement of true numbers, the arrangement of complex numbers, the arrangement of p-adic numbers, and so on. Such frameworks are not the subject of this article.

Substance  [hide]

1 Main numeral frameworks

2 Positional frameworks in point of interest

3 Generalized variable-length whole numbers

4 Devanagari numerals and their Sanskrit names

5 See additionally

6 References

7 Sources

8 External connec

Main numeral systems

The most ordinarily utilized arrangement of numerals is the Hindu–arabic numeral framework, in light of Arabic numerals. Two Indian mathematicians are credited with creating them. Aryabhata of Kusumapura created the spot esteem documentation in the fifth century and after a century Brahmagupta presented the image for zero.[1] The numeral framework and the zero idea, created by the Hindus in India gradually spread to other encompassing nations because of their business and military exercises with India. The Arabs embraced it and adjusted them. Indeed today, the Arabs call the numerals they utilize "Rakam Al-Hind" or the Hindu numeral framework. The Arabs deciphered Hindu messages on numerology and spread them to the western world because of their exchange joins with them. The Western world adjusted them and called them the Arabic numerals, as they gained from them. Subsequently the current western numeral framework is the altered form of the Hindu numeral framework created in India. It likewise displays an extraordinary closeness to the Sanskrit–devanagari documentation, which is still utilized within India.

The most straightforward numeral framework is the unary numeral framework, in which each characteristic number is spoken to by a comparing number of images. On the off chance that the image/ is picked, for instance, then the number seven would be spoken to by/. Count imprints speak to one such framework still in like manner utilization. The unary framework is valuable for little numbers, in spite of the fact that it assumes a critical part in hypothetical software engineering. Elias gamma coding, which is usually utilized within information layering, communicates subjective measured numbers by utilizing unary to demonstrate the length of a paired numeral.

The unary documentation could be truncated by presenting diverse images for certain new values. Regularly, these qualities are forces of 10; so case in point, if/ remains for one, − for ten and + for 100, then the number 304 might be minimalistically spoken to as +++/ and the number 123 as + −/ without any requirement for zero. This is called sign-esteem documentation. The aged Egyptian numeral framework was of this sort, and the Roman numeral framework was an alteration of this thought.

More helpful still are frameworks which utilize unique condensings for redundancies of images; for instance, utilizing the initial nine letters of the letter set for these shortenings, with A remaining for "one event", B "two events", etc, one could then compose C+ D/ for the number 304. This framework is utilized when composing Chinese numerals and other East Asian numerals focused around Chinese. The number arrangement of the English dialect is of this sort ("three hundred [and] four"), as are those of other talked dialects, paying little respect to what composed frameworks they have received. Nonetheless, numerous dialects use mixtures of bases, and different peculiarities, for example 79 in French is soixante dix-neuf (60 + 10 + 9) and in Welsh is pedwar ar bymtheg a thrigain (4 + (5 + 10) + (3 × 20)) or (to some degree ancient) pedwar ugain namyn un (4 × 20 − 1). In English, one could say "four score less one", as in the popular Gettysburg Address speaking to "87 years back" as "four score and seven years prior".

More exquisite is a positional framework, otherwise called spot esteem documentation. Again living up to expectations in base-10, ten separate digits 0, ..., 9 are utilized and the position of a digit is utilized to imply the force of ten that the digit is to be increased with, as in 304 = 3×100 + 0×10 + 4×1 or all the more unequivocally 3×102 + 0×101 + 4×100. Note that zero, which is not required in alternate frameworks, is of pivotal vitality here, keeping in mind the end goal to have the capacity to "skirt" a force. The Hindu–arabic numeral framework, which started in India and is currently utilized all through the world, is a positional base-10 framework.

Number-crunching is much simpler in positional frameworks than in the prior added substance ones; besides, added substance frameworks require countless images for the distinctive forces of 10; a positional framework needs just ten separate images (accepting that it uses base 10).

Positional decimal framework is in a matter of seconds generally utilized as a part of human written work. The base 1000 is additionally utilized, by gathering the digits and considering an arrangement of three decimal digits as a solitary digit. This is the importance of the regular documentation 1,000,234,567 utilized for vast numbers.

In workstations, the primary numeral frameworks are focused around the positional framework in base 2 (twofold numeral framework), with two double digits, 0 and 1. Positional frameworks got by gathering twofold digits by three (octal numeral framework) or four (hexadecimal numeral framework) are generally utilized. For vast whole numbers, bases 232 or 264 (gathering parallel digits by 32 or 64, the length of the machine word) are utilized, as, for instance, in GMP.

The numerals utilized when composing numbers with digits or images might be isolated into two sorts that may be known as the math numerals 0,1,2,3,4,5,6,7,8,9 and the geometric numerals 1, 10, 100, 1000, 10000 ..., separately. The sign-esteem frameworks utilize just the geometric numerals and the positional frameworks utilize just the math numerals. A sign-esteem framework does not require number-crunching numerals in light of the fact that they are made by reiteration (aside from the Ionic framework), and a positional framework does not require geometric numerals on the grounds that they are made by position. Then again, the talked dialect utilizes both number juggling and geometric numerals.

In specific regions of software engineering, a changed base-k positional framework is utilized, called bijective numeration, with digits 1, 2, ..., (k ≥ 1), and zero being spoken to by a vacant string. This makes a bijection between the set of all such digit-strings and the set of non-negative numbers, dodging the non-uniqueness brought about by heading zeros. Bijective base-k numeration is likewise called k-adic documentation, not to be befuddled with p-adic numbers. Bijective base-1

Positional systems in detail

See likewise: Positional documentation

In a positional base-b numeral framework (with b a common number more prominent than 1 known as the radix), b fundamental images (or digits) relating to the first b regular numbers including zero are utilized. To produce whatever remains of the numerals, the position of the image in the figure is utilized. The image in the last position has its own particular quality, and as it moves to the left its esteem is duplicated by b.

For instance, in the decimal framework (base-10), the numeral 4327 methods (4×103) + (3×102) + (2×101) + (7×100), noting that 100 = 1.

By and large, if b is the base, one composes a number in the numeral arrangement of base b by communicating it in the structure anbn + a − 1bn − 1 + a − 2bn − 2 + ... + a0b0 and composing the identified digits anan − 1an − 2 ... a0 in dropping request. The digits are common numbers somewhere around 0 and b − 1, comprehensive.

On the off chance that a content, (for example, this one) talks about numerous bases, and if uncertainty exists, the base (itself spoke to in base-10) is included subscript to the right of the number, in the same way as this: numberbase. Unless pointed out by setting, numbers without subscript are thought to be decimal.

By utilizing a dab to separation the digits into two gatherings, one can additionally compose parts in the positional framework. Case in point, the base-2 numeral 10.11 signifies 1×21 + 0×20 + 1×2−1 + 1×2−2 = 2.75.

By and large, numbers in the base b framework are of the structure:

(a_na_{n-1}\cdots a_1a_0.c_1 c_2 c_3\cdots)_b =

\sum_{k=0}^n a_kb^k + \sum_{k=1}^\infty c_kb^{-k}.

The numbers bk and b−k are the weights of the relating digits. The position k is the logarithm of the relating weight w, that is k = \log_{b} w = \log_{b} b^k. The most astounding utilized position is near the request of greatness of the number.

The amount of count imprints needed in the unary numeral framework for depicting the weight would have been w. In the positional framework, the amount of digits needed to depict it is just k + 1 = \log_{b} w + 1, for k ≥ 0. For instance, to depict the weight 1000 then four digits are required in light of the fact that \log_{10} 1000 + 1 = 3 + 1. The amount of digits needed to depict the position is \log_b k + 1 = \log_b w + 1 (in positions 1, 10, 100,... just for effortlessness in the decimal illustration).

Position 3 2 1 0 −1 −2 . . .

Weight b^3 b^2 b^1 b^0 b^{-1} b^{-2} \dots

Digit a_3 a_2 a_1 a_0 c_1 c_2 \dots

Decimal sample weight 1000 100 10 1 0.1 0.01 . . .

Decimal sample digit 4 3 2 7 0 0 . . .

Note that a number has an ending or rehashing development if and on the off chance that it is levelheaded; this does not rely on upon the base. A number that ends in one base may rehash in an alternate (along these lines 0.310 = 0.0100110011001...2). A nonsensical number stays aperiodic (with an interminable number of non-rehashing digits) in all necessary bases. Consequently, for instance in base-2, π = 3.1415926...10 could be composed as the aperiodic 11.001001000011111...2.

Putting overscores, n, or spots, ṅ, over the normal digits is a gathering used to speak to rehashing sane extensions. Subsequently:

14/11 = 1.272727272727... = 1.27  or  321.3217878787878... = 321.3217̇8̇.

In the event that b = p is a prime number, one can characterize base-p numerals whose extension to the left never stops;

Generalized variable-length integers

This is used in punycode, aspect of which is the representation of a sequence of non-negative integers of arbitrary size in the kind of a sequence without delimiters, of "digits" from a collection of 36: a�z and 0�9, representing 0�25 and 26�35 respectively. A digit lower than a threshold value marks that it is the most-significant digit, hence the finish of the number. The threshold value depends on the position in the number. For example, if the threshold value for the first digit is b (i.e. one) then a (i.e. 0) marks the finish of the number (it's digit), so in numbers of over digit the range is only b�9 (1�35), therefore the weight b1 is 35 in lieu of 36. Suppose the threshold values for the second and third digits are c (two), then the third digit has a weight 34 � 35 = 1190 and they have the following sequence:

More general is using a mixed radix notation (here written little-endian) like a_0 a_1 a_2 for a_0 + a_1 b_1 + a_2 b_1 b_2, etc.

a (0), ba (one), ca (two), .., 9a (35), bb (36), cb (37), .., 9b (70), bca (71), .., 99a (1260), bcb (1261), etc.

Unlike a regular based numeral process, there's numbers like 9b where 9 and b each represents 35; yet the representation is distinctive because ac and aca are not allowed � the a would terminate the number.

The flexibility in choosing threshold values allows optimization depending on the frequency of occurrence of numbers of various sizes.

The case with all threshold values equal to one corresponds to bijective numeration, where the zeros correspond to separators of numbers with digits which are non-zero.

Devanagari numerals and their Sanskrit names

The following is an arrangement of the Indian numerals in their advanced Devanagari structure, the relating European (Persian) equivalents, their Sanskrit articulation, and interpretations in some languages.[2]

Advanced

Devanagari persian sanskrit word for the

ordinal numeral (word stem) translations in ten

languages translations in Persian

0 śūnya (शून्य) sefr/zefr (Persian language) sefr

1 eka (एक) echad (Hebrew) yek

2 dvi (द्वि) dva (Russian) do

3 tri (त्रि) three (English) se

4 chatur (चतुर्) katër (Albanian) chahar

5 panchan (पञ्चन्) pānch (Hindi) panj

6 ṣhaṣh (षष्) seis (Spanish) shesh

7 saptan (सप्तन्) şapte (Romanian) haft

8 aṣṭan (अष्टन्) astoņi (Latvian) hasht

9 navan (नवन्) nove (Italian) no

Since Sanskrit is an Indo-European dialect, the words for numerals in Greek and Latin are like those in Sanskrit (as likewise seen from the table). The expression "shunya" for zero was deciphered into Persian dialect as "سفر" "sefr"[citation needed], signifying 'n