calculator2

Class PostfixCalculator

java.lang.Object

calculator2.PostfixCalculator

public abstract class PostfixCalculator
extends java.lang.Object

A back-end calculator for the project. Comes with its set of methods.

Author:

anurag

Constructor Summary

Constructors

Constructor and Description
PostfixCalculator()

Method Summary

Modifier and Type	Method and Description
static double	calculate_postfix(java.lang.String[] q)
static java.lang.String	calculate(java.lang.String infix_string) evaluates given infix string
static java.lang.String	remove_extra_precision(java.lang.String value) Removes extra zeros in decimal eg.
static java.lang.String[]	toPostFix(java.lang.String[] infix_array) converts infix string array to post fix string array
static java.lang.String[]	toStringArray(java.lang.String infix_string) breaks infix string to string array of its operands and operators eg.
static boolean	validate(java.lang.String infix_string) validates the infix string

Methods inherited from class java.lang.Object

equals, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

PostfixCalculator

public PostfixCalculator()

Method Detail

calculate_postfix

public static double calculate_postfix(java.lang.String[] q)
                                throws java.lang.Exception

Parameters:

q - post fix string array

Returns:

result after evaluating post fix string

Throws:

java.lang.Exception

calculate

public static java.lang.String calculate(java.lang.String infix_string)

evaluates given infix string

Parameters:

infix_string - infix string to evaluate

Returns:

(string) value after evaluation [ERROR if any exception occurred]

remove_extra_precision

public static java.lang.String remove_extra_precision(java.lang.String value)

Removes extra zeros in decimal eg. for 0.10000000000004 it will return 0.10

Parameters:

value - (String) floating point value

Returns:

result by reducing decimal value if it has consecutive 6 zeros

toPostFix

public static java.lang.String[] toPostFix(java.lang.String[] infix_array)

converts infix string array to post fix string array

Parameters:

infix_array - an array of string (operators and operands in infix)

Returns:

array of string ( post fix operands and operators)

toStringArray

public static java.lang.String[] toStringArray(java.lang.String infix_string)

breaks infix string to string array of its operands and operators eg. "a+b*c*(d+e)" to {"a","+","b","*","c","(","d","+","e",")"}

Parameters:

infix_string - (String) a correct infix string

Returns:

(String[]) array of string(operands and operators)

validate

public static boolean validate(java.lang.String infix_string)

validates the infix string

Parameters:

infix_string - (String) infix string to evaluate

Returns:

(boolean) true if it is valid expression else false