Lecture 1 - 4

What are Identifiers?

Identifiers Refers to the name given to entities such as variables, functions, structures, etc. It also must be unique.

Source code

Is a collection of computer instructions written in human-readable programming language that is usually converted to object code by a compiler.

Primitive Data Type:

Is a datatype given by a language indirectly.

Compiler

Is a software program that transforms high-level sources code that is written by a developer in a high-level programming in a low-level object code [Binary code] in machine

Object code

Is the results of what the computer compiler produces. It is also a sequence of statements or instructions in a computer language, usually a machine code language [I.E. Binary] Object files can in turn be linked to form an executable file, library file, or an object file

Assembler

It is a language processor that tranlates symbolic assembly language into relevant machine language. Characteristics: 1. Assemblers provide Symbolic/representative labels in which they are attached to constants and memory addresses. 2. The use of mnemonics which are used to specify the processor instructions plus specific supporting operations needed of the assembler language. 3. The branch target address is easier to put into the program when the editor isn't concerned with actual value but may need to mention by name. 4. The constants in the language may be or may not be specified of several different bases with decimals, octal and binary. 5. It can scan the source program twice while translation is occurring in the machine coding, that being very common options.

What is Literal?

It is a value that is written as how it should be interpreted.

Psuedocode

It is an informal program description that does not contain code syntax or underlying considerations. It summarizes a program's steps or flow but excludes underlying details

Interpreter

It is hardware or software that transforms one statement at a time of a program in high-level languages in a certain sequence of mechanical languages. Characteristics: 1. The interpreter language makes the simple syntax easy to learn and use 2. It assumes the smallest software design information 3. The language permits complex instructions to be completed in very few steps 4. It also permits simple design and editing in a lot of different text editors 5. The interpreter language of active and interactive activities to web pages.

What is a constant?

It is similar to a variable in a memory location that holds a value, however, a constant's value doesn't change

What are some of the benefits of Modularity?

Less code has to be written. Codes reusability, allows for components to be developed independently of each other, ability to collaborate on the same application, code is separated amongst multiple files, the code is more concise and easily understood and it is easier to debug.

What is Modularity?

Modular programing is a software design technique that emphasizes separating the functionality of a program into independent, interchangeable modules, such that each contains everything necessary to execute only one aspect of the desired functionality.

Low-level Language

Programming language that deals with a computer's hardware components and constraints . It is a computers native language. It is closer to computers . Its prime function is to operate, manage. Program and applications written in low level language are direction executable on the computing hardware without and interpretation or translation. Lowlevel examples: Machine and assembly language

High-Level Language

Programming language that enables development of a program in much simpler programming context and is generally independent of the computer's hardware architecture. It has a higher level of abstraction from the computer, and focuses more on the programming logic rather than the underlying hardware components such as memory addressing and register utilization. Their programming style and context is easier to learn and implement and the entire code generally focuses on the specific program to be created. It doesnt require addressing hardware constraints to a greater extent when developing a program. Every single program written in a high-level language must be interpreted into machine language before being executed by the computer. an example of a high level language is Java, C/C++. Characteristics: - It is close to human language. - It is easy to learn and use. - It is not machine dependent. - It provides large number of built in functions. - Program written in high level language is slower execution. - No deep knowledge is required to learn and use high level language. - There are many programmers that can write programs in high level language. - It is easy to trace out errors in the program written in high level language. - High level languages are commonly used. - The program statement written in high level language is very short.

Terminal (Stop/Start)

Represents start and end of a flowchart

Naming a Variable

Starts with a letter or an underscore. Uses an underscore of clarity. Can use numbers but not at the sta

Local vs Global

The global variable scope encompasses the entire program therefore at no time will the variable be considered undefined. Where as a local variable scope is confined to a small section of the program and any reference to that variable outside off it's scope will cause a runtime error stating of it's scope will cause a runtime error stating that the variable is undefined.

Sentinel- Controlled Loops

The type of loop where the number of execution is unknown, is termed by Sentinel controlled loop. In this case the value of the control variable differs within a limitation and the execution can be terminated at any moment as the value of the Variable is not controlled by the loop. The control variable in this case is termed by sentinel variable.

What are Counter-Controlled Loops?

The type of loop, where the number of the execution is known in advance are termed by the counter controlled loop. That means, in this case, the value of the variable which controls the execution of the loop is previously known. The control variable is known as Counter. A counter controlled loop is also called definite repetition loop.

What is Homogeneous Data Structure?

These data structures contain a variety of data. For example, that can contain various data of different data types like integers, float and character.

What are Flowcharts helpful for?

They are helpful for: aiding the understanding of relationships among different process steps and collecting data about a particular process. It is also helpful for helping with a decision making. Measuring the performance of a process. Depicting the structure of a process.Tracking the process flow. Highlighting important steps and eliminating the unnecessary steps

What is the IF contrusct?

This is a type of selection control that alters the flow of a program depending on a conidition.

What is the Down-Up Approach

This is another approach to problem solving that is used to tackle complex problems. Regarding programming, the bottom-up approach solves a problem by looking at the simple components/elements of a program and then continuously combining those small components/ elements combining those small components/elements into bigger components that will eventually achieves desired outcome.

Processing

Used for arithmetic operations and data-manipulations

Inout/output

Used for input and output operation.

Off-page connector

Used to connect flowchart portion on different page

On-page Connector

Used to join different flowline

Predefined Process/Function

Used to represent a group

Desicion

Used to represent the operation in which there are two alternatives, true and false.

What is an Array Data Structure?

What is an Array Data Structure? An array is a data structure that contains a group of elements. Typically, these elements are all of the same data type, such as an integer or string. Arrays are commonly used in computer programs to organize data so that values can easily sorted or searched.

Accumulating

adds the value in number to the variable total.

What is the Top-Down Approach

his approach to problem solving is used to break down a problem into more manageable sections until all sections are simple to comprehend and tackle. The top-down approach can be applied to programming tasks as well. A programming problem can be so complex that the only way to comprehend it is to break it up into manageable components or modules and further break up those into more smaller items.

FlowLine

indicate the flow of logic by connecting symbols

CASE Statement

is another type of selection control structure that alters the flows of a program depending on a condition and is quite similar to the IF construct. However, this type of evaluates an expression then searches amongst the different cases for a match and if none is provided the default is used.

Computer Program

- A set of instructions understood by the computer used to accomplish a specific task when executed.

Syntax

- It refers to the rules that specify the correct combined sequence of symbols that can be used to form a correctly structured program using a given programming language - Programmers communicate with computers through the correctly structured syntax, semantics and grammar of a programming language. - It contains strings similar to words, much like a human language. Correctly formed syntax strings produce syntactically correct sentences within a specified programming language. - Syntax describes how language variable and characters may be combined into strings When you hear syntax, you should think of, instructions, and structure.

SEMANTICS

- This refers to the usage of words, symbols and labels to support a logical outcome. Semantics focuses on the meaning behind a statement or expression of a programming language. [Example]: Assigning a string to a variable that can only store integers 1. Assigning a string to a variable that can only store integers.

Programming Language

-It is a computer language engineered to create a standard form of commands. These commands can be interpreted into a code understood by a machine. -Programs are created through programming languages to control the behavior and output of a machine through accurate algorithms, similar to the human communication process. -A programming language is typically divided into two elements: syntax and semantics. There is pretty much always a specification document to define Both elements. [Example]: an ISO standard defines C.

What is a flowchart?

A flowchart is a type of diagram representing a process using different symbols containing information about steps that are linked with arrows to illustrate the flow direction of the process. Flowcharts are a methodology used to analyze, improve, document and manage a process or program.

What is a Variable Scope?

A scope refers to an area in which an entity is still defined or has meaning. In programming, a variable scope refers to an area in which a variable is still accessible and defined. Typically, there are two variable scopes in programming: Local and Global.

Algorithm

A set of rules that allows a computer to solve a problem.

Pseudocode

A simple way of writing programming code in English.

What is a variable?

A variable is a location in memory that stores information. It is referenced or accessed by used a label. As its name state, it can also store information in that memory location can be altered at will.

Counting

Adds 1 to the variable

Application Software

Also known as Productivity Program. These are applications are used to carry out operation or tasks not related system maintenance or performance tuning. E.G. Offices Suites. Web Browsers. Instant Messaging tools

Complex/ structure data type.

Any data that does not fall into the traditional field structure (alpha, numeric, dates) of a relational DBMS.

System Software

Applications that are used for the main purpose of managing the resources of the computer. - may increase performance or provide a communication mechanism for external and internal device/system to communicate with each other. [Example] - Operating system -Device driver - Different operating system -Vista -Mac -XP -Linux

What are some of the characteristics of Low Level Languages.

Close to machine languages. Difficult to learn and use. machine dependent. written in low level languages is faster in execution.