首页 | 主题 | 图库 | 问答 | 文摘 | 原创 | 百科

历史 | 地理 | 人物 | 艺术 | 体育 | 科学 | 音乐 | 电影 | 信息技术 | 世界遗产

 开放、中立，源自维基百科

个人工具


用搜狗搜索相关网站  Google Search

计算器

维库，知识与思想的自由文库

跳转到: 导航, 搜索

翻譯標記 本條目仍然有文字尚未被翻譯成中文，條目是根據en:Calculator進行翻譯。
歡迎您積極參與翻譯與修訂，目前翻譯的進度為2%。
舊型機械計算器
舊型機械計算器
科學型計算器
科學型計算器
會計型計算器
會計型計算器

计算器（calculator），是一种小型的手持或桌面的裝置，用於完成計算。現代的計算器與计算机是不一樣，计算器通常仅能完成算术运算和少量逻辑操作并显示其结果，但一般不能修改其程序。除了某些尺寸可比掌上型計算器的PDA之外，計算器的可攜性通常高於计算机。


目录

[编辑] 概觀

在過去，諸如算盤、納皮爾骨頭、數學表書籍、工程计算尺或機械加法機（adding machine）在數值計算上扮演輔助角色。計算器這詞原本指的是以紙筆執行數學計算的職業人士，這樣的半手動計算工作既繁重又易出錯。

現代的計算器以電力為動力，且擁有從便宜、信用卡尺寸的簡易裝置到附列印功能的特殊計算器等多種形狀與尺寸。

[编辑] 電子計算器

過去有些計算器像是今日的電腦一樣大，第一個機械計算器是桌上型機械裝置，但很快被桌上型電力機械計算器取代，之後又被真空管、電晶體、積體電路邏輯線路等材料依序取代。今日大部分計算器是掌上型微電子裝置。


[编辑] 基本計算器

計算器的複雜度隨著使用目的而有所不同。最簡單的計算器模組應該包含下列部件：

  • 電源，例如電池或太陽能版（solar panel）
  • 顯示幕，通常以LED光源或LCD製成，可顯示一定數量的數字（通常八到十位）
  • 電子迴路
  • 一個包含下列按鍵的按鍵面版：
    • 十個數字鍵，從0到9
    • 小數點
    • 等於符號，用於顯示運算解
    • 四個運算函式（加減乘除）
    • 取消鍵，用於清空目前顯示的數字
    • 電源開關
    • 其他基本函數，例如求平方根或百分比鍵 （%）
  • 更高級的模組也許會有一個單數值記憶按鍵（M+，M-），可在需要時叫回。

1980年代早期，基本計算器開始置入其他小型裝置，例如手機、BBCall（pager）或腕錶。

[编辑] 進階電子計算器

一TI-89計算器的3D線框模型擷圖
一TI-89計算器的3D線框模型擷圖

較高階的'科學計算器或工程型計算器支援三角函數、統計與其他函數。而最先進的現代計算器甚至可顯示圖型，並且包含電腦代數系統。這種計算器可以編寫程式，且內含了代數方程式求解程式、經濟模型甚至遊戲程式。這類計算器可顯示填滿螢幕的單一數值。並可將數字以科學記數法表現至9.999999999*1099。如果使用者試圖輸入一過大的數值或運算產生過大數值的算式（例如輸入100!，即100階乘），則計算器僅顯示錯誤一詞。因為記憶體如此有限的計算器無法儲存如此巨大的輸入。

錯誤也用以表示數學上未定義的函數或操作，例如除以零或對負數取平方根（除了某些昂貴的計算器擁有可處理複數的特殊函數，大部分科學計算器不允許複數的存在）。某些少數計算器可分別這兩種錯誤的不同，雖然使用者依然難以瞭解error 1與error2的差別何在。

僅有少數公司研發與製造現代職業工程師與經濟學家用的計算器：最有名的是Casio、夏普、HP與德州儀器。這些計算器都是嵌入式系統的典範。

[编辑] 教育用途

學生正在使用計算器
學生正在使用計算器

大部分已開發國家的學生常在寫回家作業時使用計算器。但因擔心學生的基本算術能力因而受到伐害，因此許多人士抗拒讓學生過早使用它。而某些課程限制使用計算器運算算術，直到學到更高階的計算技巧；其他人則不同意以紙筆或心算算術的重要性，他們更注重教授評估（estimation）與解決問題的技巧。

然而，還是有一些其他顧慮：例如學生可能以錯誤的方式使用計算器，並因對計算器的信賴而盲目相信答案。教師為了破解學生的盲信，常會指導學生以人工驗算並確認其答案的正確性。當然，學生也有可能只運用計算器取得答案，而不瞭解運算的真實意義，例如輸入-10 × -10，獲得"100"，卻不瞭解背後「負負得正」的規則。在此情況下，計算器成為學生的依賴而非輔助工具，使學生在考試時對任何簡單的運算都以計算器求解，並降低應答的速度。

[编辑] 其他使用上的顧慮

Errors are not restricted to school pupils. Any user could carelessly rely on the calculator's output without double-checking the magnitude of the result - i.e., where the decimal point is positioned. This problem was all but nonexistent in the era of slide rules and pencil-and-paper calculations, when the task of establishing the magnitudes of results had to be done by the user.

Some fractions such as ⅔ are awkward to display on a calculator display as they are usually rounded to 0.66666667. Also, some fractions such as 0.14285714... can be difficult to recognize in decimal form - in fact, this number is 1/7. Some of the more advanced scientific calculators are able to work in vulgar fractions, although the operation in practice is somewhat awkward.

會計型計算器
會計型計算器

[编辑] 計算器與電腦

A fundamental difference between calculators and most computers is that calculators are numeric tools only, while computers may use numbers to directly manipulate words, images, or sounds, for example.

The market for calculators is extremely price-sensitive; typically the user cares primarily about what is the least expensive model having a specific feature set, but does not care much about speed (since speed is primarily constrained by how fast the user can press the buttons). Thus designers of calculators strive to minimize the number of logic elements on the chip, not the number of clock cycles needed to do a computation.

For instance, instead of a hardware multiplier, a calculator might implement floating point mathematics with code in ROM, and compute trigonometric functions with the CORDIC algorithm because CORDIC does not require floating-point. For similar reasons, bit-serial logic designs are more common in calculators whereas bit-parallel designs dominate general-purpose computers: a bit-serial design minimizes the chip complexity but takes many more clock cycles.

Personal computers and personal digital assistants can perform general calculations in a variety of ways:

[编辑] 歷史

[编辑] 最早：算盤

中式算盤
中式算盤
主条目：算盤

第一個計算器是算盤。算盤通常以木框加上在木桿上滑動的木珠製成。在西方，算盤在印度阿拉伯數字流行前使用了數個世紀，且在近代中國的記帳與商務上仍廣泛使用。

[编辑] 17世紀

Wilhelm Schickard built the first automatic calculator called the "Calculating Clock" in 1623. Some 20 years later, in 1643, French philosopher Blaise Pascal invented the calculation device later known as the Pascaline, which was used for taxes in France until 1799. The German philosopher G.W.v. Leibniz also produced a calculating machine.

[编辑] 19世紀

巴貝奇將計算工具的概念更往前推，試圖建立第一個可編程式電腦，但這台他建造的機器太重了，因而無法操作。

[编辑] 1930年代至1960年代

1914年的機械計算器
1914年的機械計算器

From the 1930s through the 1960s, mechanical calculators dominated the desktop computing market (see History of computing hardware). Major suppliers in the USA included Friden, Monroe, and SCM/Marchant. (Some comments about European calculators follow below.) These devices were motor-driven, and had movable carriages where results of calculations were displayed by dials. Nearly all keyboards were full — each digit that could be entered had its own column of nine keys, 1..9, plus a column-clear key, permitting entry of several digits at once. (See the illustration of a 1914 mechanical calculator.) One could call this parallel entry, by way of contrast with ten-key serial entry that was commonplace in mechanical adding machines, and is now universal in electronic calculators. (Nearly all Friden calculators had a ten-key auxiliary keyboard for entering the multiplier when doing multiplication.) Full keyboards generally had ten columns, although some lower-cost machines had eight. Most machines made by the three companies mentioned did not print their results, although other companies, such as Olivetti, did make printing calculators.

In these machines, Addition and subtraction were performed in a single operation, as on a conventional adding machine, but multiplication and division were accomplished by repeated mechanical additions and subtractions. Friden made a calculator that also provided square roots, basically by doing division, but with added mechanism that automatically incremented the number in the keyboard in a systematic fashion. Friden was the only company who made a calculator with square root. Handheld mechanical calculators such as the 1948 Curta continued to be used until they were displaced by electronic calculators in the 1970s.

In 1954, IBM demonstrated a large all-transistor calculator and, in 1957, they released the first commercial all-transistor calculator (the IBM 608). In early 1961, the world's first all-electronic desktop calculator, the Bell Punch/Sumlock Comptometer ANITA (A New Inspiration To Arithmetic) Mk.VII was released. This British designed-and-built machine used vacuum tubes in its circuits and cold-cathode Nixie tubes for its display. This model was somewhat error-prone, and was replaced in September 1961 with the much more successful Mark VIII version. The ANITA had a full keyboard, and was, very likely, the only such electronic calculator. It was superseded technologically in June 1963, by the Friden EC-130, which had an all-transistor design, 13-digit capacity on a 5-inch CRT, and introduced reverse Polish notation (RPN) to the calculator market for a price of $2200, which was about triple the cost of an electromechanical calculator of the time. In 1964 Sharp introduced the CS-10A, also an all-transistor desktop calculator, which weighed 25 kg (55 lb) and cost 500,000 yen (~US$2500).

The Facit, Triumphator, and Walther calculators shown below are typical European machines. Similar-looking machines included the Odhner and Brunsviga, among others. Although these are operated by handcranks, there were, of course, motor-driven versions. Most machines that look like these use the Odhner mechanism, or variations of it. The Olivetti Divisumma did all four basic operations of arithmetic, and has a printer. Full-keyboard machines, including motor-driven ones, were also used in Europe for many decades. Some European machines, probably rare, had as many as 20 columns in their full keyboards.

Facit NTK (1954)
Facit NTK (1954)
Triumphator CRN1 (1958)
Triumphator CRN1 (1958)
Walther WSR160 (1960)
Walther WSR160 (1960)
Olivetti Divisumma 24 (1964)
Olivetti Divisumma 24 (1964)
Image:Calculating machine "felix".jpg
Felix (1960-x)

[编辑] 1970年代至1980年代中期

In the early 1970s, the Monroe Epic programmable calculator came on the market. A large desk-top unit, with an attached floor-standing logic tower, it was capable of being programmed to perform many computer-like functions. However, the only branch instruction was an implied unconditional branch (GOTO) at the end of the operation stack, returning the program to its starting instruction. Thus, it was not possible to include any conditional branch (IF-THEN-ELSE) logic. During this era, the absence of the conditional branch was sometimes used to distinguish a programmable calculator from a computer.

The first hand-held calculator, introduced in January, 1971, was the Sharp EL-8, also marketed as the Facit 1111. It weighed about one pound, had a vacuum fluorescent display, rechargeable NiCad batteries, and initially sold for $395. The first American-made pocket-sized calculator, the Bowmar 901B (popularly referred to as The Bowmar Brain), measuring 5.2×3.0×1.5 in (131×77×37 mm), came out in the fall of 1971, with four functions and an eight-digit red LED display, for $240, while in August 1972 the four-function Sinclair Executive became the first slimline pocket calculator measuring 5.4×2.2×0.35 in (138×56×9 mm) and weighing 2.5 oz (70g). It retailed for around $150 (GB£79). By the end of the decade, similar calculators were priced less than $10 (GB£5).

The first pocket calculator with scientific functions that could replace a slide rule was 1972's $395, HP-35 from Hewlett Packard (HP). Along with all later HP engineering calculators, it used reverse Polish notation (RPN), also called postfix notation. A calculation like "8 plus 5" is, using RPN, performed by pressing "8", "Enter↑", "5", and "+"; instead of the algebraic infix notation: "8", "+", "5", "=").

In 1973, Texas Instruments (TI) introduced the SR-10, (SR signifying slide rule) an algebraic entry pocket calculator, which was later followed by the SR-11 and eventually the TI-30.

The first programmable pocket calculator was the HP-65, in 1974; it had a capacity of 100 instructions, and could store and retrieve programs with a built-in magnetic card reader. A year later the HP-25C introduced continuous memory, i.e. programs and data were retained in CMOS memory during power-off. In 1979, HP released the first alphanumeric, programmable, expandable calculator, the HP-41C. It could be expanded with RAM (memory) and ROM (software) modules, as well as peripherals like bar code readers, microcassette and floppy disk drives, paper-roll thermal printers, and miscellaneous communication interfaces (RS-232, HP-IL, HP-IB).

[编辑] 1980年代中期至現代

The first calculator capable of symbolic computation was the HP-28, released in 1987. It was able to, for example, solve quadratic equations symbolically. The first graphing calculator was the Casio fx7000G released in 1985.

The two leading manufacturers, HP and TI, released increasingly feature-laden calculators during the 1980s and 1990s. At the turn of the millennium, the line between a graphing calculator and a PDA/handheld computer was not always clear, as some very advanced calculators such as the TI-89 and HP-49G could differentiate and integrate functions, run word processing and PIM software, and connect by wire or IR to other calculators/computers.

In March 2002, HP announced that the company would no longer produce calculators, which was hard to fathom for some fans of the company's products; the HP-48 range in particular had an extremely loyal customer base. HP restarted their production of calculators in late 2003. The new models, however, reportedly didn't have the mechanical quality and sober design of HP's earlier calculators for which HP calculators were once famous (instead featuring the more "youthful" look and feel of contemporary competing designs from TI). In the early days of the calculator, HP sales reps were famous for starting demonstrations by slamming the calculator on the floor. But today calculators are regarded as cheap, disposable gadgets.

CASIO CM-602迷你電子計算器在1970年代提供了基本功能
CASIO CM-602迷你電子計算器在1970年代提供了基本功能

The HP 12c financial calculator is still produced. It was introduced in 1981 and is still being made with few changes. The HP 12c featured the reverse Polish notation mode of data entry. In 2003 several new models were released, including an improved version of the HP 12c, the "HP 12c platinum edition" which added more memory, more built-in functions, and the addition of the algebraic mode of data entry.

[编辑] 趣聞

  • The word "calculator" is occasionally used as a pejorative term to describe an inadequately capable general-purpose microcomputer. The synonym of this meaning is "bitty box", as discussed in the Jargon File.
  • Some words and simple phrases can be written using an ordinary seven-segment display calculator; this involves entering certain numbers and then viewing the resulting words by turning the calculator display upside-down. For example, entering 0.7734 and then turning the display upside-down will form the word 'hello'.
由德州儀器製作的TI-89圖形計算器
由德州儀器製作的TI-89圖形計算器

[编辑] 参见

線上計算器：

軟體計算器：

其他領域：

機械計算器：

電子計算器：

[编辑] 專利權

– Complex computer – G. R. Stibitz, Bell Laboratories, 1954 (filed 1941, refiled 1944), electromechanical (relay) device that could calculate complex numbers, record, and print results by teletype

– Miniature electronic calculator – J. S. Kilby, Texas Instruments, 1974 (originally filed 1967), handheld (3 lb, 1.4 kg) battery operated electronic device with thermal printer

– Extended Numerical Keyboard with Structured Data-Entry Capability – J. H. Redin, 1997 (originally filed 1996), Usage of Verbal Numerals as a way to enter a number.

– Floating Point Calculator With RAM Shift Register - 1977 (originally filed GB Mar 1971, US Jul 1971), very early single chip calculator claim.

[编辑] 外部連結

current models

history

Pen based calculator

  • [1] gives a novel pen-based calculator that will work on whiteboards or tablets.

Virtual calculators



數學小作品 这是一个与数学相关的小作品，您可以帮助维库扩充其内容。
来自“http://wwww.51txl.com/wiki/%E8%AE%A1%E7%AE%97%E5%99%A8”
导航
其它语言
AD Links