Conditional STATEMENTS
Normally, the statements are executed sequentially as written in the program (i.e. Top to bottom). This is known as the normal flow of control. But sometimes the operational flow of control has to
be altered depending upon a condition. The statements that allow to do so, are known as selection statements. Most important selection statement that python offers is the If statement.
Selection statements are also known as conditional statements or decision statements.
THE IF STATEMENT
An if statement tests a particular condition; if the condition evaluates to true, a course of action is followed i.e. a statement of a set of statements is executed. If the condition is false the course of action is ignored.
The syntax of if statement is as shown below:
if (expression) :
Statement
THE ELIF STATEMENT
In some cases the program requires you to write multiple if statements. This results in many condition evaluations thus slowing up the program. So to avoid this elif statements can be used.
Unlike if statement elif statements stops further evaluation of conditional statement once a condition is true. The keyword ‘elif‘ is short for ‘else if’, and is useful to avoid excessive indentation.
An if ... elif ... elif ... sequence is a substitute for
the switch or case statements found in other languages.
USING ELSE
If all the conditions inside conditional statements are false then
the body of the else loop will be executed.
If (expression) :
Statement1
Elif(expression):
Statement2
Else:
Statement3
If , elif and else this way, together form the if-elif-else ladder
Normally, the statements are executed sequentially as written in the program (i.e. Top to bottom). This is known as the normal flow of control. But sometimes the operational flow of control has to
be altered depending upon a condition. The statements that allow to do so, are known as selection statements. Most important selection statement that python offers is the If statement.
Selection statements are also known as conditional statements or decision statements.
THE IF STATEMENT
An if statement tests a particular condition; if the condition evaluates to true, a course of action is followed i.e. a statement of a set of statements is executed. If the condition is false the course of action is ignored.
The syntax of if statement is as shown below:
if (expression) :
Statement
THE ELIF STATEMENT
In some cases the program requires you to write multiple if statements. This results in many condition evaluations thus slowing up the program. So to avoid this elif statements can be used.
Unlike if statement elif statements stops further evaluation of conditional statement once a condition is true. The keyword ‘elif‘ is short for ‘else if’, and is useful to avoid excessive indentation.
An if ... elif ... elif ... sequence is a substitute for
the switch or case statements found in other languages.
USING ELSE
If all the conditions inside conditional statements are false then
the body of the else loop will be executed.
If (expression) :
Statement1
Elif(expression):
Statement2
Else:
Statement3
If , elif and else this way, together form the if-elif-else ladder
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