1.
HP 35s
–
The HP 35s is the latest in Hewlett-Packards long line of non-graphing programmable scientific calculators. Although it is a successor to the HP 33s, it was introduced to commemorate the 35th anniversary of the HP-35, the HP 35s uses either Reverse Polish Notation or algebraic infix notation as input. However, it far more functions, processing power. The physical appearance and keyboard layout of the HP 35s is very different than that of its predecessor, the HP 33s. The primary differences are, The HP 35s allows both label and line number addressing in programs, the HP 33s had only label addressing. With only 26 labels, it was difficult to write programs making use of the entire 30 KB of memory, the memory in the HP 35s is also usable for data storage, in the form of an extra 801 numbered memory registers. Support for vector operations is new in the HP 35s, complex numbers are treated as a single value instead of two separate values. Indirect branching, which allows the contents of a register to be used as the target of a branching instruction is omitted from the HP 35s. No arbitrary limit to length of equations, HP has released a free-of-charge 35s emulator for the Windows operating system. This was previously available to teachers for classroom demonstration purposes. The HP 35s was designed by Hewlett-Packard in conjunction with Kinpo Electronics of Taiwan, according to HP, the calculator has been engineered for heavy-duty professional use, and has been tested under extreme environmental conditions. It is built using 25 screws for rigidity and ease of maintenance, the faceplate is metal, bonded to the plastic case. The key legends are printed, rather than the double-shot moulding used in the vintage models, the calculator is powered by two CR2032 button cells, which it is advised to replace one at a time, to avoid memory loss. The calculator is entirely self-contained, there is no facility for upgrading the firmware, nor for loading/saving programs, particular mention has been made of the traditional HP feel of the keyboard with a big ↵ Enter key back in its traditional place. Shortcomings which have been identified include the lack of any facility for communication with a computer, response to the calculators logic has been mixed. The increase in addressable registers and introduction of program line-number addressing have been seen as a big improvement over the 33s, while welcoming the improved handling of complex numbers compared to the 33s, the incomplete support for them has been criticised. Working with hexadecimal and other non-decimal bases has been criticised as requiring excessive and unintuitive keystrokes, several firmware bugs have also been reported, which are not known to have been fixed as of 2015. The 35ss lack of communication makes it acceptable for use in some professional examinations where more powerful calculators would not be
2.
Calculator
–
An electronic calculator is a small, portable electronic device used to perform operations ranging from basic arithmetic to complex mathematics. The first solid state electronic calculator was created in the 1960s, building on the history of tools such as the abacus. It was developed in parallel with the computers of the day. The pocket sized devices became available in the 1970s, especially after the first microprocessor and they later became used commonly within the petroleum industry. Modern electronic calculators vary, from cheap, give-away, credit-card-sized models to sturdy desktop models with built-in printers and they became popular in the mid-1970s. By the end of decade, calculator prices had reduced to a point where a basic calculator was affordable to most. In addition to general purpose calculators, there are designed for specific markets. For example, there are scientific calculators which include trigonometric and statistical calculations, some calculators even have the ability to do computer algebra. Graphing calculators can be used to graph functions defined on the real line, as of 2016, basic calculators cost little, but the scientific and graphing models tend to cost more. In 1986, calculators still represented an estimated 41% of the worlds general-purpose hardware capacity to compute information, by 2007, this diminished to less than 0. 05%. Modern 2016 electronic calculators contain a keyboard with buttons for digits and arithmetical operations, most basic calculators assign only one digit or operation on each button, however, in more specific calculators, a button can perform multi-function working with key combinations. Large-sized figures and comma separators are used to improve readability. Various symbols for function commands may also be shown on the display, fractions such as 1⁄3 are displayed as decimal approximations, for example rounded to 0.33333333. Also, some fractions can be difficult to recognize in decimal form, as a result, Calculators also have the ability to store numbers into computer memory. Basic types of these only one number at a time. The variables can also be used for constructing formulas, some models have the ability to extend memory capacity to store more numbers, the extended memory address is termed an array index. Power sources of calculators are, batteries, solar cells or mains electricity, some models even have no turn-off button but they provide some way to put off. Crank-powered calculators were also common in the computer era
3.
Scientific calculator
–
A scientific calculator is a type of electronic calculator, usually but not always handheld, designed to calculate problems in science, engineering, and mathematics. They have almost completely replaced slide rules in almost all traditional applications, there is also some overlap with the financial calculator market. A few have multi-line displays, with recent models from Hewlett-Packard, Texas Instruments, Casio, Sharp. By providing a method to enter an entire problem in as it is written on the page using simple formatting tools, the HP-35, introduced on February 1,1972, was Hewlett-Packards first pocket calculator and the worlds first handheld scientific calculator. Like some of HPs desktop calculators it used RPN, introduced at US$395, the HP-35 was available from 1972 to 1975. Texas Instruments, after the introduction of units with scientific notation, came out with a handheld scientific calculator on January 15,1974. TI continues to be a player in the calculator market. Casio and Sharp have also been major players, with Casios fx series being a common brand. Casio is also a player in the graphing calculator market
4.
Light-emitting diode
–
A light-emitting diode is a two-lead semiconductor light source. It is a p–n junction diode, which emits light when activated, when a suitable voltage is applied to the leads, electrons are able to recombine with electron holes within the device, releasing energy in the form of photons. This effect is called electroluminescence, and the color of the light is determined by the band gap of the semiconductor. LEDs are typically small and integrated optical components may be used to shape the radiation pattern, appearing as practical electronic components in 1962, the earliest LEDs emitted low-intensity infrared light. Infrared LEDs are still used as transmitting elements in remote-control circuits. The first visible-light LEDs were also of low intensity and limited to red, modern LEDs are available across the visible, ultraviolet, and infrared wavelengths, with very high brightness. Early LEDs were often used as indicator lamps for electronic devices and they were soon packaged into numeric readouts in the form of seven-segment displays and were commonly seen in digital clocks. Recent developments in LEDs permit them to be used in environmental, LEDs have allowed new displays and sensors to be developed, while their high switching rates are also used in advanced communications technology. LEDs have many advantages over incandescent light sources including lower energy consumption, longer lifetime, improved physical robustness, smaller size, and faster switching. Light-emitting diodes are now used in applications as diverse as aviation lighting, automotive headlamps, advertising, general lighting, traffic signals, camera flashes, as of 2017, LED lights home room lighting are as cheap or cheaper than compact fluorescent lamp sources of comparable output. They are also more energy efficient and, arguably, have fewer environmental concerns linked to their disposal. Electroluminescence as a phenomenon was discovered in 1907 by the British experimenter H. J. Round of Marconi Labs, using a crystal of silicon carbide, russian inventor Oleg Losev reported creation of the first LED in 1927. His research was distributed in Soviet, German and British scientific journals, rubin Braunstein of the Radio Corporation of America reported on infrared emission from gallium arsenide and other semiconductor alloys in 1955. Braunstein observed infrared emission generated by simple diode structures using gallium antimonide, GaAs, indium phosphide, in 1957, Braunstein further demonstrated that the rudimentary devices could be used for non-radio communication across a short distance. As noted by Kroemer Braunstein …had set up a simple optical communications link, the emitted light was detected by a PbS diode some distance away. This signal was fed into an amplifier and played back by a loudspeaker. Intercepting the beam stopped the music and we had a great deal of fun playing with this setup. This setup presaged the use of LEDs for optical communication applications, by October 1961, they had demonstrated efficient light emission and signal coupling between a GaAs p-n junction light emitter and an electrically-isolated semiconductor photodetector
5.
Seven-segment display
–
A seven-segment display, or seven-segment indicator, is a form of electronic display device for displaying decimal numerals that is an alternative to the more complex dot matrix displays. Seven-segment displays are used in digital clocks, electronic meters, basic calculators. The seven elements of the display can be lit in different combinations to represent the arabic numerals, often the seven segments are arranged in an oblique arrangement, which aids readability. The numerals 6 and 9 may be represented by two different glyphs on seven-segment displays, with or without a tail, the seven segments are arranged as a rectangle of two vertical segments on each side with one horizontal segment on the top, middle, and bottom. Additionally, the seventh segment bisects the rectangle horizontally, there are also fourteen-segment displays and sixteen-segment displays, however, these have mostly been replaced by dot matrix displays. Twenty-two segment displays capable of displaying the full ASCII character set were available in the early 1980s. The segments of a 7-segment display are referred to by the letters A to G, for gasoline price totems and other large signs, vane displays made up of electromagnetically flipped light-reflecting segments are still commonly used. An alternative to the 7-segment display in the 1950s through the 1970s was the cold-cathode, starting in 1970, RCA sold a display device known as the Numitron that used incandescent filaments arranged into a seven-segment display. Integrated displays also exist, with single or multiple digits, some of these integrated displays incorporate their own internal decoder, though most do not, each individual LED is brought out to a connecting pin as described. Multiple-digit LED displays as used in calculators and similar devices used multiplexed displays to reduce the number of I/O pins required to control the display. For example, all the anodes of the A segments of each digit position would be connected together and to a driver circuit pin, while the cathodes of all segments for each digit would be connected. In this manner an eight digit display with seven segments and a point would require only 8 cathode drivers and 8 anode drivers, instead of sixty-four drivers. A single byte can encode the full state of a 7-segment-display, the most popular bit encodings are gfedcba and abcdefg, where each letter represents a particular segment in the display. In the gfedcba representation, a value of 0x06 would turn on segments c and b. In 1908, F. W. Wood invented an 8-segment display, in 1910, a seven-segment display illuminated by incandescent bulbs was used on a power-plant boiler room signal panel. They were also used to show the dialed telephone number to operators during the transition from manual to automatic telephone dialing and they did not achieve widespread use until the advent of LEDs in the 1970s. For many applications, dot-matrix LCDs have largely superseded LED displays, unlike LEDs, the shapes of elements in an LCD panel are arbitrary since they are formed on the display by a kind of printing process. The seven-segment display has inspired designers to produce typefaces reminiscent of that display, such as New Alphabet, DB LCD Temp, ION B
6.
Reverse Polish notation
–
Reverse Polish notation is a mathematical notation in which every operator follows all of its operands, in contrast to Polish notation, which puts the operator before its operands. It is also known as postfix notation and it does not need any parentheses as long as each operator has a fixed number of operands. The description Polish refers to the nationality of logician Jan Łukasiewicz, the algorithms and notation for this scheme were extended by Australian philosopher and computer scientist Charles Hamblin in the mid-1950s. In computer science, postfix notation is used in stack-based. It is also common in dataflow and pipeline-based systems, including Unix pipelines, most of what follows is about binary operators. An example of a unary operator whose standard notation uses postfix is the factorial, in reverse Polish notation the operators follow their operands, for instance, to add 3 and 4, one would write 34 + rather than 3 +4. An advantage of RPN is that it removes the need for parentheses that are required by infix notation, while 3 −4 ×5 can also be written 3 −, that means something quite different from ×5. In postfix, the former could be written 345 × −, which unambiguously means 3 − which reduces to 320 −, the latter could be written 34 −5 ×, which unambiguously means 5 ×. In comparison testing of reverse Polish notation with algebraic notation, reverse Polish has been found to lead to faster calculations, because reverse Polish calculators do not need expressions to be parenthesized, fewer operations need to be entered to perform typical calculations. Additionally, users of reverse Polish calculators made fewer mistakes than for other types of calculator, however, anecdotal evidence suggests that reverse Polish notation is more difficult for users to learn than algebraic notation. The algorithm for evaluating any postfix expression is fairly straightforward, While there are input tokens left Read the next token from input, if the token is a value Push it onto the stack. Otherwise, the token is an operator and it is already known that the operator takes n arguments. If there are fewer than n values on the stack The user has not input sufficient values in the expression, else, Pop the top n values from the stack. Evaluate the operator, with the values as arguments, Push the returned results, if any, back onto the stack. If there is one value in the stack That value is the result of the calculation. Otherwise, there are more values in the stack The user input has too many values,12 +4 ×5 +3 − Edsger Dijkstra invented the shunting-yard algorithm to convert infix expressions to postfix, so named because its operation resembles that of a railroad shunting yard. There are other ways of producing postfix expressions from infix notation, one of the designers of the B5000, Robert S. Designed by Robert Bob Appleby Ragen, Friden introduced RPN to the calculator market with the EC-130 supporting a four-level stack in June 1963
7.
Hewlett-Packard
–
The Hewlett-Packard Company or shortened to Hewlett-Packard was an American multinational information technology company headquartered in Palo Alto, California. The company was founded in a garage in Palo Alto by William Bill Redington Hewlett and David Dave Packard. HP was the worlds leading PC manufacturer from 2007 to Q22013 and it specialized in developing and manufacturing computing, data storage, and networking hardware, designing software and delivering services. HP also had services and consulting business around its products and partner products.4 billion in 2008, in November 2009, HP announced the acquisition of 3Com, with the deal closing on April 12,2010. On April 28,2010, HP announced the buyout of Palm, on September 2,2010, HP won its bidding war for 3PAR with a $33 a share offer, which Dell declined to match. On October 6,2014, Hewlett-Packard announced plans to split the PC and printers business from its enterprise products, the split closed on November 1,2015, and resulted in two publicly traded companies, HP Inc. and Hewlett Packard Enterprise. William Redington Hewlett and David Packard graduated with degrees in engineering from Stanford University in 1935. The company originated in a garage in nearby Palo Alto during a fellowship they had with a past professor, Terman was considered a mentor to them in forming Hewlett-Packard. In 1939, Packard and Hewlett established Hewlett-Packard in Packards garage with a capital investment of US$538. Hewlett and Packard tossed a coin to decide whether the company they founded would be called Hewlett-Packard or Packard-Hewlett, HP incorporated on August 18,1947, and went public on November 6,1957. Of the many projects they worked on, their very first financially successful product was an audio oscillator. This allowed them to sell the Model 200A for $54.40 when competitors were selling less stable oscillators for over $200, the Model 200 series of generators continued until at least 1972 as the 200AB, still tube-based but improved in design through the years. They worked on technology and artillery shell fuses during World War II. Hewlett-Packards HP Associates division, established around 1960, developed semiconductor devices primarily for internal use, instruments and calculators were some of the products using these devices. HP partnered in the 1960s with Sony and the Yokogawa Electric companies in Japan to develop several high-quality products, the products were not a huge success, as there were high costs in building HP-looking products in Japan. HP and Yokogawa formed a joint venture in 1963 to market HP products in Japan, HP bought Yokogawa Electrics share of Hewlett-Packard Japan in 1999. HP spun off a company, Dynac, to specialize in digital equipment. The name was picked so that the HP logo hp could be turned upside down to be a reverse image of the logo dy of the new company
8.
Trigonometric functions
–
In planar geometry, an angle is the figure formed by two rays, called the sides of the angle, sharing a common endpoint, called the vertex of the angle. Angles formed by two rays lie in a plane, but this plane does not have to be a Euclidean plane, Angles are also formed by the intersection of two planes in Euclidean and other spaces. Angles formed by the intersection of two curves in a plane are defined as the angle determined by the tangent rays at the point of intersection. Similar statements hold in space, for example, the angle formed by two great circles on a sphere is the dihedral angle between the planes determined by the great circles. Angle is also used to designate the measure of an angle or of a rotation and this measure is the ratio of the length of a circular arc to its radius. In the case of an angle, the arc is centered at the vertex. In the case of a rotation, the arc is centered at the center of the rotation and delimited by any other point and its image by the rotation. The word angle comes from the Latin word angulus, meaning corner, cognate words are the Greek ἀγκύλος, meaning crooked, curved, both are connected with the Proto-Indo-European root *ank-, meaning to bend or bow. Euclid defines a plane angle as the inclination to each other, in a plane, according to Proclus an angle must be either a quality or a quantity, or a relationship. In mathematical expressions, it is common to use Greek letters to serve as variables standing for the size of some angle, lower case Roman letters are also used, as are upper case Roman letters in the context of polygons. See the figures in this article for examples, in geometric figures, angles may also be identified by the labels attached to the three points that define them. For example, the angle at vertex A enclosed by the rays AB, sometimes, where there is no risk of confusion, the angle may be referred to simply by its vertex. However, in geometrical situations it is obvious from context that the positive angle less than or equal to 180 degrees is meant. Otherwise, a convention may be adopted so that ∠BAC always refers to the angle from B to C. Angles smaller than an angle are called acute angles. An angle equal to 1/4 turn is called a right angle, two lines that form a right angle are said to be normal, orthogonal, or perpendicular. Angles larger than an angle and smaller than a straight angle are called obtuse angles. An angle equal to 1/2 turn is called a straight angle, Angles larger than a straight angle but less than 1 turn are called reflex angles
9.
Exponential function
–
In mathematics, an exponential function is a function of the form in which the input variable x occurs as an exponent. A function of the form f = b x + c, as functions of a real variable, exponential functions are uniquely characterized by the fact that the growth rate of such a function is directly proportional to the value of the function. The constant of proportionality of this relationship is the logarithm of the base b. The argument of the function can be any real or complex number or even an entirely different kind of mathematical object. Its ubiquitous occurrence in pure and applied mathematics has led mathematician W. Rudin to opine that the function is the most important function in mathematics. In applied settings, exponential functions model a relationship in which a constant change in the independent variable gives the same change in the dependent variable. The graph of y = e x is upward-sloping, and increases faster as x increases, the graph always lies above the x -axis but can get arbitrarily close to it for negative x, thus, the x -axis is a horizontal asymptote. The slope of the tangent to the graph at each point is equal to its y -coordinate at that point, as implied by its derivative function. Its inverse function is the logarithm, denoted log, ln, or log e, because of this. The exponential function exp, C → C can be characterized in a variety of equivalent ways, the constant e is then defined as e = exp = ∑ k =0 ∞. The exponential function arises whenever a quantity grows or decays at a proportional to its current value. One such situation is continuously compounded interest, and in fact it was this observation that led Jacob Bernoulli in 1683 to the number lim n → ∞ n now known as e, later, in 1697, Johann Bernoulli studied the calculus of the exponential function. If instead interest is compounded daily, this becomes 365, letting the number of time intervals per year grow without bound leads to the limit definition of the exponential function, exp = lim n → ∞ n first given by Euler. This is one of a number of characterizations of the exponential function, from any of these definitions it can be shown that the exponential function obeys the basic exponentiation identity, exp = exp ⋅ exp which is why it can be written as ex. The derivative of the function is the exponential function itself. More generally, a function with a rate of change proportional to the function itself is expressible in terms of the exponential function and this function property leads to exponential growth and exponential decay. The exponential function extends to a function on the complex plane. Eulers formula relates its values at purely imaginary arguments to trigonometric functions, the exponential function also has analogues for which the argument is a matrix, or even an element of a Banach algebra or a Lie algebra
10.
William Redington Hewlett
–
William Bill Redington Hewlett was an American engineer and the co-founder, with David Packard, of the Hewlett-Packard Company. Hewlett was born in Ann Arbor, Michigan where his father taught at the University of Michigan Medical School. In 1916 the family moved to San Francisco after his father, Albion Walter Hewlett, took a position at Stanford Medical School. He attended Lowell High School and was accepted at Stanford University as a favor to his father who had died of a brain tumor in 1925. He joined the Kappa Sigma fraternity during his time at Stanford, Hewlett attended undergraduate classes taught by Fred Terman at Stanford and became acquainted with David Packard. Packard and he began discussing forming a company in August 1937, a flip of a coin decided the ordering of their names. Their first big breakthrough came when Disney purchased multiple audio oscillators designed by Hewlett for use in the production of the film Fantasia, the company incorporated in 1947 and tendered an initial public offering in 1957. Bill Hewlett and Dave Packard were very proud of their culture which came to be known as the HP Way. The HP Way is a culture that claimed to be not only centered on making money. Hewlett was president of the Institute of Radio Engineers in 1954 and he was president of HP from 1964 to 1977, and served as CEO from 1968 to 1978, when he was succeeded by John A. Young. He remained chairman of the committee until 1983, and then served as vice chairman of the board until 1987. A young Steve Jobs, then age 12, called Hewlett, Hewlett, impressed with Jobs gumption, offered him a summer job assembling frequency counters. Jobs then considered HP one of the companies that he admired, regarding it among the handful of companies that were built “to last, Hewlett served in the Army during World War II as a Signal Corps Officer. He then led the section of the Development Division, a new part of the War Department Special Staff. After the war he was part of a team that inspected Japanese Industry. Hewlett was a Director for Hexcel Products Incorporated from 1956-1965, Hewlett served as a Director of Chase Manhattan Bank from 1969-1980. Hewlett was also elected to the Board of Directors for Chrysler Corporation in 1966, starting in the 1960s Hewlett committed much of his time and wealth towards numerous philanthropic causes. In 1966, William Hewlett and his wife Flora founded the William and Flora Hewlett Foundation, aside from the foundation Hewlett gave millions to universities, schools, museums, non-profits, and other organizations
11.
France Rode
–
France Rode is an engineer and inventor best known for his work on the HP-35 pocket calculator. He was one of the four lead engineers at Hewlett-Packard assigned to this project, Rode also invented and created the first workable RFID products, workplace entry cards, for which he holds several patents. France was born in Nožice, Slovenia on November 20,1934 to farmers father Jože and mother Pepca, born Prešeren and his younger sister Agata and brothers Marko and Aleš completed the family. France started elementary education in nearby Homec soon after the German occupation of Slovenia during the Second World War. A few months into the first school year the local partisans burned the school building, due to an accelerated learning program, France completed the fourth grade in Homec in 1947 and in the fall of the same year began attending high school in Kamnik. He skipped the fifth grade by studying and passing exams designed for the fifth grade during the summer months and his academic interests at that time were in mathematics, physics and natural sciences. Whenever he had to study, France was excused from farm work, however, living on the farm allowed him no time for extracurricular activities for which he envied his schoolmates. Only occasionally he managed to join his peers after school and his fondest memories of such activities include participating in the staging of Hamlet, directed by Ciril Gostič, brother of operas singer Joze Gostic, France’s Godfather. His nostalgic memories also include skiing trips to Mala Planina and staying with his ski buddies in “Steletova koča. ”Living on the farm did have some side benefits, France learned hard work habits and discovered his inventive drive. In his uncle’s carpentry shop next door, he built his own toys and he made the slide rule he used during all his academic years in Ljubljana. France planned to study mathematics at Ljubljana University, but altered his interest to electrical engineering after he visited the University’s electrical engineering laboratories and he felt that in this field he would be able to combine his interest in mathematics with some hands-on work. France’s early contact with the world outside Slovenia, were two summer jobs in Germany and a few school excursions and these contacts subsequently led him to visit companies in Sweden, Denmark, the Netherlands, and Germany, which exposed him to advanced technologies of that era. They also triggered in him a desire to more about new places. France earned a degree in bio-medicine at Northwestern University in 1962. In September of the year he joined Hewlett-Packard Company in Palo Alto. During his years at Hewlett-Packard, France was able to participate in the development of new technologies in modern electronics. He was not just witnessing the birth and growth of Silicon Valley, which was then the center of technological progress. When a new measuring instrument needed a unit, France was given the task of designing it