Programming notations
1 like1,675 views
This document defines key concepts in computer programming including variables, programs, and Hungarian notation. It explains that a computer accepts input, manipulates data through processing according to a program's instructions, and outputs and stores results. Computers excel at computation and have replaced manual calculation. Proper programming requires understanding the computer's language of operators, terminologies, and symbols to create expressions that computers can interpret through compilers or interpreters. Arithmetic, relational, and logical operators perform specific math, comparison, or logic operations on operands like variables or numbers. Operator order follows PEMDAS rules for evaluating expressions accurately. Examples show converting a math expression into a programming expression using the proper operators.
Programming notations
- 1. Essential Concepts and Terminologies: 1. Variable – The primary storage location that can assume different numeric or alphanumeric values. 2. Computer Program – A set of logical instructions given to a computer for data processing that is interpreted by a compiler to produce useful information. 3. Hungarian Notation – A variable naming convention suggested by Microsoft. Introduction A computer is a fast-electronic programmable device operating under the controls of instructions(program). The device can accept data (input), manipulate data(process), produce results from the manipulation(output), and store the results for future use(storage). The term computer is derived from the word “compute” that suggests computation or calculation. Computers are incredibly good at math. Peopleware (people who uses computer) used to spend hours calculating results from their formulas and data. Now, a computer can "compute" results for them in a fraction of a second. A computer can work efficiently if given a proper instruction through a program. It is therefore a must for computer programmers to learn the language the computer can understand. This COMPUTER LANGUAGE is composed of arithmetic operators, logical operators, relational operators, important terminologies and symbols which programmers can use to create mathematical expressions. PROGRAMMING NOTATIONS
- 2. Arithmetic Operators Relational Operators Logical Operators An OPERATOR in a programming language is a symbol that tells the computer (compiler or interpreter) to perform specific mathematical, relational or logical operation and produce final result. Here they are. Study each of these operators in order to understand how they work within the EXPRESSIONS. An operator performs an action on one or more operands (variables or numbers). Arithmetic Operators Relational Operators Logical Operators
- 3. Mathematical Expressions Programming Expressiion Final Value 3𝑎𝑏 3*a*b 30 𝑎2 + 𝑏2 a*a + b*b or a^2 + b^2 29 8𝑎 𝑏3 (8*a)/(b*b*b) or (8*a)/(b^3) 5 𝑎2 + 𝑏2 𝑎𝑏 ((a*a)+(b*b))/(a*b) or (a^2)+(b^2)/(a*b) 2.9 Operators in arithmetic expressions follow the rules from mathematics. It is important to note that the arithmetic hierarchy of computation still applies in computers. Computer will first evaluate expressions inside the parenthesis, power or exponentiation is evaluated before multiplication and division, while the former two ( x ÷ ⤳ * / ) are evaluated before addition and subtraction. PEMDAS rule applies in evaluating an expression (Parenthesis, Exponentiation, Multiplication, Division, Addition and Subtraction). In order for computers to understand our EXPRESSIONS, we must first know how to convert from mathematical expressions to programming expression using the operators. Let’s try to practice. Assuming we have (variable) a with a value of 5, and b with a value of 2, we will use the letters aand bin the expression. Remember, letters aand brepresents the numbers 5 and 2 respectively. The caret sign ^ denotes exponentiation in programming expression.
- 4. Example: Convert the arithmetic expression ab(a2+b2) to computer expression, we first change the operators. Take note that if two letters (variables) are side-by-side with the others, the operation is to multiply. Then, ab ⤳ a*b | b( ⤳ b*( | a2 ⤳ a^2. Therefore, arithmetic expression: ab(a2+b2) in computer expression is: a*b*(a^2+b^2) let’s substitute the values having a=2and b=3: *ba Notice how we insert the operators between the letters (variables) and numbers. Arithmetic Expressions ab(a2+b2) Substituted values 2*b*(a^2+b^2) Computer Expressions 2*b*(a*a+b*b) or 2*3*(2^2+3^2) 2*3*(2*2+3*3) or The final value is 78 Note that in some programming languages, the operators vary in their use. For example, others would use <> for NOT EQUAL TO, or the Caret ^ maybe of another function rather than exponentiation. What we have here are the basic operators. Additional operators will be defined by other programming language.