程序设计语言毕业论文外文文献翻译.doc

A 英文翻译资料Programming LanguageProgramming language, in computer science, are the artificial languages used to write a sequence of instructions (a computer program) that can be run by a computer. Similar to natural languages, such as English, programming languages have a vocabulary, grammar, and syntax. However, natural languages are not suited for programming computers because they are ambiguous, meaning that their vocabulary and grammatical structure may be interpreted in multiple ways. The languages used to program computers must have simple logical structures, and the rules for their grammar, spelling and punctuation must be precise.Programming languages vary greatly in their sophistication and in their degree of versatility. Some programming languages are written to address a particular kind of computing problem or for use on a particular model of computer system. For instance, programming languages such as FORTRAN and COBOL were written to sole certain general types of programming problems FORTRAN for scientific applications, and COBOL for business applications. Although these languages were designed to address specific categories of computer problems, they are highly portable, meaning that they may be used to program many types of computers. Other languages, such as machine languages, are designed to be used by one specific model of computer system, or even by one specific computer in certain research applications. The most commonly used programming languages are highly portable and can be used to effectively solve diverse types of computing problems. Languages like C, PASCAL, and BASIC fall into this category.Programming languages can be classified as either low-level languages or high-level languages. Low-level programming languages, or machine languages, are the most basic type of programming languages and can be understood directly by a computer. High-level languages are programming languages that must first be translated into a machine language before they can be understood and processed by a computer. Examples of high-level languages are C, C+, PASCAL, and FROTRAN. Assembly languages are intermediate languages that are very close to machine languages and do not have the level of linguistic sophistication exhibited by other high-level languages, but must still be translated into machine language.1.Machine LanguagesIn machine languages, instructions are written as sequences of 1s and 0s, called bits, that a computer can understand directly. An instruction in machine language generally tells the computer four things: (1) where to find one or two numbers or simple pieces of data in the main computer memory (Random Access Memory, or RAM), (2) a simple operation to perform, such as adding the two number together, (3) where in the main memory to put the result of this simple operation, and (4) where to find the next instruction to perform. While all executable programs are eventually read by the computer in machine language, they are not all programmed in machine language. It is extremely difficult to program directly in machine language because the instructions are sequences of 1s and 0s. A typical instruction in a machine language might read 10010 1100 1011 and mean add the contents of storage register A to the contents of storage register B.2 .High-Level LanguagesHigh-Level languages are relatively sophisticated sets of statements utilizing words and syntax from human language. They are more similar to normal human language than assembly or machine languages and are therefore easier to use for writing complicated programs. These programming languages allow larger and more complicated programs to be developed faster. However, high-lever languages must be translated into machine language by another program called a compiler before a computer can understand them. For this reason, programs written in a high-level language may take longer to execute and use up more memory than programs written in an assembly language.3. Assembly LanguagesComputer programmers use assembly languages to make machine language programs easier to write. In an assembly language, each statement corresponds roughly to one machine language instruction. An assembly language statement is composed with the aid of easy-to-remember commands. The command to add the contents of storage register A to the contents of storage register B might be written ADD B,A in a typical assembly language statement. Assembly languages share certain features with machine languages. For instance, it is possible to manipulate specific bits in both assembly and machine languages. Programmers use assembly languages when it is important to minimize the time it takes to run a program, because the translation from assembly language to machine language is relatively simple. Assembly languages are also used when some part of the computer has to be controlled directly, such as individual dots on a monitor or the flow of individual characters to a printer.B 中文翻译程序设计语言编程语言，在计算机科学，是用来编写的指令序列（计算机程序），可以由计算机上运行的人造语言。类似的，自然的语言，例如英语，编程语言有一个词汇，语法和语法。然而，自然语言不适合计算机编程，因为他们是含糊不清，这意味着他们的词汇和语法结构可以以多种方式来解释。用于程序的计算机必须有简单的逻辑结构的语言，和他们的语法，拼写和标点符号的规则必须是准确的。编程语言差别很大的复杂性和在其多功能性程度。一些编程语言编写的计算，以解决问题或对一特定型号的计算机系统使用特定类型。举例来说，如FORTRAN语言和COBOL的编程语言被写入唯一的某些一般的规划问题，FORTRAN语言语言类型的科学应用，以及商业应用的COBOL语言。虽然这些语言的目的是解决计算机问题的具体类别，它们是高度可移植的，这意味着它们可用于多种类型的计算机程序。如机器语言，其他语言的目的是由一个计算机系统，甚至在某些研究一个具体应用的计算机的特定模型。最常用的编程语言是高度可移植的，可以用来有效地解决不同类型的计算问题。如ç学，PASCAL的，基本属于这一类的语言。编程语言可以被归类为低层次的语言或高级语言。高级语言的节目，必须先翻译成，才可以被理解的机器语言，由计算机处理的语言。高层次的语言例如C语言，C + +，PASCAL的，和FROTRAN。大会语言是非常接近机器语言，并没有对其他高级语言表现语言的中间语言的复杂程度，但仍必须翻译成机器语言。1.Machine语言在机器语言，指令被写为1和0，称为序列位，一台计算机可以直接理解。在机器语言指令告诉计算机一般四件事情：（1）在哪里可以找到一个或两个数或在主计算机的内存（随机存取记忆体，或RAM）数据的简单件，（2）一个简单的操作来执行，如添加了两个数字一起，（3）如在主内存来把这个简单的操作的结果，以及（4）在哪里可以找到下一个指令来执行。虽然所有的可执行程序，最终由计算机在机读语言，他们不是在所有机器语言编程。这是非常困难的方案，因为直接在机器语言的指令是1和0序列。如果一个典型的机器语言指令可能会读取10010 1100 1011，平均添加的内容存储到存储寄存器A的内容登记乙 2.高级语言高级语言是利用人类语言的文字和语法相对复杂的报表集。他们更接近正常比汇编语言的人或机器语言，因此更容易编写复杂的程序使用。这些编程语言允许更大，更复杂的方案，以获得更快的发展。然而，高杠杆的语言必须转化成机器语言的另一个称为编译程序之前，计算机能理解他们。基于这个原因，方案写在一个高层次的语言可能需要更长的时间来执行和使用更多的内存在1比汇编语言编写的程序。 3.汇编语言使用汇编语言的计算机程序员，使机器语言程序更容易编写。在一个汇编语言，每个语句大致相当于一台机器语言指令。汇编语言语句组成的易记的援助命令。汇编语言与机器语言共享某些特征。例如，它可以操纵机器语言都装配和具体位。使用汇编语言编程时，重要的是要尽量减少所花费的时间运行程序，因为从汇编语言翻译成机器语言是比较简单。汇编语言也被用来当一些计算机的一部分，必须直接控制，例如监视器或个别字流向打印机个别点。5