General computer calculation
MPE, 8gflops
CPE, 11gflops
the peak computing power of Shenwei Taihu Lake light system reaches 100pflops<
it is necessary to mention here that floating-point computing power refers to the processing power of computer floating-point computing, and the computer has a special floating-point processor FPU for floating-point processing.
home computer 2G Hz, 4G Hz refers to the dominant frequency of the computer, the dominant frequency is 4G Hz, and the floating-point processing power of the computer is about 4gflops. However, the dominant frequency is not equal to floating-point processing power
dominant frequency means the number of computer clock cycles per second. The more processing per second, the more powerful the computer is
the main frequency of CPU does not represent the processing power of CPU and the influence of instruction pipeline on the processing power of CPU
clock cycle is the basic unit of CPU operation, and a floating-point calculation may need several to dozens of clock cycles. So the relationship between the dominant frequency and floating-point processing power is obvious.
the birth and development of modern computer before the advent of modern computer, the development of computer has gone through three stages: mechanical computer, electromechanical computer and electronic computer
as early as the 17th century, a group of European mathematicians began to design and manufacture digital computers that perform basic operations in digital form. In 1642, Pascal, a French mathematician, made the earliest decimal adder by using a gear transmission similar to clocks and watches. In 1678, Leibniz, a German mathematician, developed a computer to further solve the multiplication and division of decimal numbers
British mathematician Babbage put forward an idea when he made the model of difference machine in 1822. One arithmetic operation at a time will develop into a certain complete operation process automatically. In 1884, Babbage designed a program-controlled universal analyzer. Although this analyzer has described the rudiment of the program control computer, it can not be realized e to the technical conditions at that time< During the more than 100 years since Babbage's idea was put forward, great progress has been made in electromagnetics, electrotechnics and electronics, and vacuum diodes and vacuum triodes have been successively invented in components and devices; In terms of system technology, wireless telegraph, television and radar were invented one after another. All these achievements have prepared technical and material conditions for the development of modern computer< At the same time, mathematics and physics are developing rapidly. In the 1930s, all fields of physics experienced the stage of quantification. The mathematical equations describing various physical processes, some of which were difficult to solve by classical analysis methods. As a result, numerical analysis has been paid attention to, and various numerical integration, numerical differentiation, and numerical solutions of differential equations have been developed. The calculation process has been reced to a huge amount of basic operations, thus laying the foundation of modern computer numerical algorithm
the urgent need for advanced computing tools in society is the fundamental driving force for the birth of modern computers. Since the 20th century, there have been a lot of computational difficulties in various fields of science and technology, which has hindered the further development of the discipline. Especially before and after the outbreak of the Second World War, the need for high-speed computing tools in military science and technology is particularly urgent. During this period, Germany, the United States and the United Kingdom started the research of electromechanical computer and electronic computer almost at the same time<
Giuseppe in Germany was the first to use electrical components to make computers. The fully automatic relay computer Z-3, which he made in 1941, has the characteristics of modern computer, such as floating-point counting, binary operation, instruction form of digital storage address and so on. In the United States, the relay computers mark-1, mark-2, model-1, model-5 and so on were made successively from 1940 to 1947. However, the switching speed of the relay is about one hundredth of a second, which greatly limits the computing speed of the computer
the development process of electronic computer has experienced the evolution from making components to whole machine, from special machine to general machine, from "external program" to "stored program". In 1938, the Bulgarian American scholar atanasov first made the computing unit of the electronic computer. In 1943, the communications office of the British Foreign Office made the "giant" computer. This is a special cryptanalysis machine, which was used in the Second World War< In February 1946, ENIAC, a large-scale electronic digital integrator computer, was developed by Moore College of the University of Pennsylvania in the United States. At first, ENIAC was also specially used for artillery trajectory calculation. Later, it was improved many times and became a general-purpose computer capable of various scientific calculations. This computer, which uses electronic circuit to perform arithmetic operation, logic operation and information storage, is 1000 times faster than relay computer. This is the first electronic computer in the world. However, the program of this kind of computer is still external, the storage capacity is too small, and it has not fully possessed the main characteristics of modern computer
the new breakthrough was completed by a design team led by mathematician von Neumann. In March 1945, they published a new general electronic computer scheme of stored program - electronic discrete variable automatic computer (EDVAC). Then in June 1946, von Neumann and others put forward a more perfect design report "preliminary study on the logical structure of electronic computer devices". From July to August of the same year, they taught a special course "theory and technology of electronic computer design" for experts from more than 20 institutions in the United States and Britain at Moore college, which promoted the design and manufacture of stored program computers< In 1949, the Mathematics Laboratory of Cambridge University in England took the lead in making EDSAC; The United States made the eastern standard automatic computer (SFAC) in 1950. At this point, the embryonic period of the development of electronic computer came to an end, and the development period of modern computer began
at the same time of creating digital computer, we also developed another kind of important computing tool analog computer. When physicists summarize the laws of nature, they often use mathematical equations to describe a process; On the contrary, the process of solving mathematical equations may also adopt the physical process simulation method. After the invention of logarithm, the slide rule made in 1620 has changed multiplication and division into addition and subtraction for calculation. Maxwell skillfully transformed the calculation of integral (area) into the measurement of length, and made the integrator in 1855< Fourier analysis, another great achievement of mathematical physics in the 19th century, played a direct role in promoting the development of simulators. In the late 19th century and the early 20th century, a variety of analytical machines for calculating Fourier coefficients and differential equations were developed. However, when trying to popularize the differential analysis machine to solve partial differential equations and use the simulator to solve general scientific calculation problems, people graally realize the limitations of the simulator in the aspects of universality and accuracy, and turn their main energy to the digital computer
after the advent of electronic digital computer, analog computer still continues to develop, and hybrid computer is proced by combining with digital computer. Simulators and mixers have become special varieties of modern computers, that is, efficient information processing tools or simulation tools used in specific fields
since the middle of the 20th century, the computer has been in a period of high-speed development. The computer has developed from a hardware only system to a computer system which includes three subsystems: hardware, software and firmware. The performance price ratio of computer system is increased by two orders of magnitude every 10 years. The types of computers have been divided into microcomputers, minicomputers, general-purpose computers (including giant, large and medium-sized computers), and various special computers (such as various control computers and analog-to-digital hybrid computers)
computer devices, from electron tubes to transistors, from discrete components to integrated circuits to microprocessors, have made three leaps in the development of computers< In the period of electron tube computer (1946-1959), computers were mainly used for scientific calculation. Main memory is the main factor that determines the appearance of computer technology. At that time, the main memory included mercury delay line memory, cathode ray oscilloscope electrostatic memory, magnetic drum and magnetic core memory, which were usually used to classify computers.
hope to adopt
the daily cash withdrawal limit of ATM is 20000
different ATM settings are different, some are single transaction 2000, some are 2500, 3000, at most 5000 per transaction; At the time of withdrawal, ATM will prompt the maximum amount of each withdrawal
automatic teller machine, also known as ATM, is the abbreviation of automatic teller machine, which means automatic teller machine. Because most of it is used for withdrawal, it is also known as ATM. It is a highly precise mechatronics device, using magnetic code card or smart card to achieve self-service of financial transactions, instead of the work of bank counter staff. It can withdraw cash, inquire deposit balance, transfer funds between accounts, inquire balance, etc; It can also carry out cash deposit (real-time entry), check deposit (none in China), passbook re registration, intermediate business, etc. Cardholders can use a credit card or savings card to make automatic withdrawal, balance inquiry, transfer, cash deposit, passbook re registration, purchase funds, change passwords, and pay mobile phone bills according to their passwords strong>
if you play 360 games with PC through simulator,
you are in a circle.
you should understand the story of tortoise and rabbit race
Why do computers work so fast
because the arithmetic unit and controller in the electronic computer are composed of bistable circuit and various "gate" circuits; In other words, they are calculated by using the high-speed transmission characteristics of electricity. We know that the transmission speed of electricity is 300000 kilometers per second, which is very fast. Therefore, the computing speed of the electronic computer is very fast< Secondly, the operation of electronic computer is very simple. No matter how complicated the problem is, as long as the personnel design the calculation program in advance and send the calculation program together with the original data to the computer, it can automatically calculate the original data step by step according to the manual program. Each operation is very simple. For example, to add, you only need to do 1 + 1 = 10, 1 + 0 = 1, 0 + 1 = 1, 0 + 0 = 0. There are only four cases (subtraction, multiplication and division are the same). Such a simple calculation, primary school students can quickly work out. Because the calculation is simple, the arithmetic unit can also be very simple; In other words, the bistable circuit and "gate" circuit are needed less, and the electronic path is also less, which makes the operation speed faster.