Package parser

Class MathScanner

  • public class MathScanner
extends java.lang.Object
    Author:
    GBEMIRO

    • Constructor Summary

      Constructors 
      Constructor Description
      MathScanner​(java.lang.String scannerInput)  

    • Method Summary

      Modifier and Type Method Description
      static void $removeExcessBrackets​(java.util.List<java.lang.String> scanner)
      This technique conserves the last single bracket as it is unsure of the rules that allow it to unwrap the last bracket.
      static void extractFunctionStringFromExpressionForMatrixMethods​(java.util.List<java.lang.String> list)
      Analyzes the list and extracts the Function string from it.
      java.util.ArrayList<java.lang.String> getErrorList()  
      static java.lang.String getFirstNumberSubstring​(java.lang.String val)
      method getFirstNumberSubstring takes a String object and returns the first number string in the String.
      java.util.ArrayList<java.lang.String> getNumberStrings​(java.lang.String val)
      method getNumberStrings takes a String object and returns an ArrayList of substrings of all numbers in the input String
      java.util.ArrayList<java.lang.String> getScanner()  
      java.lang.String getScannerInput()  
      boolean isRunnable()  
      static void main​(java.lang.String[] args)  
      void plusAndMinusStringHandler()
      Handles repeated concatenations of plus and minus operators.
      static void recognizeAnonymousFunctions​(java.util.List<java.lang.String> scanner)  
      static void removeExcessBrackets​(java.util.List<java.lang.String> scanner)
      This technique will rid tokens of offending brackets up to the last bracket.
      java.util.ArrayList<java.lang.String> scanner()
      Utility method,more popularly used as a scanner into mathematical tokens of mathematical expressions.
      java.util.ArrayList<java.lang.String> scanner​(VariableManager varMan)
      Utility method,more popularly used as a scanner into mathematical tokens of mathematical expressions
      void setErrorList​(java.util.ArrayList<java.lang.String> errorList)  
      void setRunnable​(boolean runnable)  
      void setScanner​(java.util.ArrayList<java.lang.String> scanner)  
      void setScannerInput​(java.lang.String scannerInput)  
      java.util.ArrayList<java.lang.String> splitStringAtFirstNumber​(java.lang.String val)  
      void splitStringOnMethods_Variables_And_Operators()
      Split the scannerInput String on the operators.
      java.util.ArrayList<java.lang.String> splitStringOnNumbers​(java.lang.String val)
      method splitStringOnNumbers takes a String object and returns an ArrayList of substrings in which the original string has been split into different parts based on the amount of number substrings it has.
      void validateInputAfterSplitOnMethodsAndOps()
      Check that variables and methods do not conflict..if that can happen.
      void validateTokens()
      Identifies that the input is a valid one by checking that all tokens are either Number objects, Variable objects or Operator objects.

      • Methods inherited from class java.lang.Object

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

    • Constructor Detail

      • MathScanner

        public MathScanner​(java.lang.String scannerInput)
        Parameters:
        scannerInput - the input of this Scanner object

    • Method Detail

      • setScannerInput

        public void setScannerInput​(java.lang.String scannerInput)
        Parameters:
        scannerInput - sets the input of this Scanner object

      • getScannerInput

        public java.lang.String getScannerInput()
        Returns:
        the input into the scanner.

      • setScanner

        public void setScanner​(java.util.ArrayList<java.lang.String> scanner)
        Parameters:
        scanner - sets the ArrayList object that holds the scanned output.

      • getScanner

        public java.util.ArrayList<java.lang.String> getScanner()
        Returns:
        the ArrayList object that holds the scanned output.

      • setRunnable

        public void setRunnable​(boolean runnable)
        Parameters:
        runnable - sets whether object of this class are runnable on a calculating device or not.

      • isRunnable

        public boolean isRunnable()
        Returns:
        true if the object of this class is runnable on a calculating device.

      • setErrorList

        public void setErrorList​(java.util.ArrayList<java.lang.String> errorList)
        Parameters:
        errorList - sets the list of errors.

      • getErrorList

        public java.util.ArrayList<java.lang.String> getErrorList()
        Returns:
        the list of errors.

      • getFirstNumberSubstring

        public static java.lang.String getFirstNumberSubstring​(java.lang.String val)
                                                throws java.lang.StringIndexOutOfBoundsException
        method getFirstNumberSubstring takes a String object and returns the first number string in the String.
        Parameters:
        val - the string to analyze
        Returns:
        the index of the first occurrence of a number character in the sequence.
        Throws:
        java.lang.StringIndexOutOfBoundsException

      • splitStringAtFirstNumber

        public java.util.ArrayList<java.lang.String> splitStringAtFirstNumber​(java.lang.String val)
        Parameters:
        val - the String to analyze
        Returns:
        an ArrayList consisting of 2 or 3 parts. a. If a number substring starts the string,then it returns an ArrayList object containing the number substring and the part of the string after the number. e.g. for 231.62A+98B+sin45C, the method returns [231.62,A+98B+sin45C] b. If a number substring does not start the string but occurs later on in it, the method returns an ArrayList object containing (i.)the substring from index 0 up to, but not including the index where the first number occurs. (ii.)The number substring (iii.)The remaining part of the string after the number. The method will not be used directly by developers but will be used as a tool in math expression scanning.

      • splitStringOnNumbers

        public java.util.ArrayList<java.lang.String> splitStringOnNumbers​(java.lang.String val)
        method splitStringOnNumbers takes a String object and returns an ArrayList of substrings in which the original string has been split into different parts based on the amount of number substrings it has.
        Parameters:
        val - the string to analyze e.g if val="123.234+43.6",the output will be [123.234,+,43.6]
        Returns:
        An ArrayList of substrings consisting of number substrings and the other substrings of the input.
        Throws:
        java.lang.StringIndexOutOfBoundsException

      • getNumberStrings

        public java.util.ArrayList<java.lang.String> getNumberStrings​(java.lang.String val)
        method getNumberStrings takes a String object and returns an ArrayList of substrings of all numbers in the input String
        Parameters:
        val - the string to analyze e.g if val="123.234+43.6",the output will be [123.234,43.6]
        Returns:
        An ArrayList of substrings consisting of number substrings and the other substrings of the input.
        Throws:
        java.lang.StringIndexOutOfBoundsException

      • splitStringOnMethods_Variables_And_Operators

        public void splitStringOnMethods_Variables_And_Operators()
        Split the scannerInput String on the operators.

      • validateInputAfterSplitOnMethodsAndOps

        public void validateInputAfterSplitOnMethodsAndOps()
        Check that variables and methods do not conflict..if that can happen. Now method names and variable names are similar. The only difference between them is that methods use parentheses while variables don't. Enforce especially then that variable-parenthesis combinations that may be mistaken for methods are not allowed. e.g sin(..) is a method. A user may name a variable sin, if he/she so wishes. make sure that the user does not do things like.. varname(expr..). Rather, he/she must separate variables from parentheses using the multiplication operator.

      • validateTokens

        public void validateTokens()
        Identifies that the input is a valid one by checking that all tokens are either Number objects, Variable objects or Operator objects. Then it registers any Variable object found and initializes it to zero.

      • plusAndMinusStringHandler

        public void plusAndMinusStringHandler()
        Handles repeated concatenations of plus and minus operators.

      • scanner

        public java.util.ArrayList<java.lang.String> scanner()
        Utility method,more popularly used as a scanner into mathematical tokens of mathematical expressions. This method does not check expression variables against declared variables and is only useful in breaking down the input into scanned tokens of numbers,variables and operators. The overloaded one takes a VariableManager object that models the store of Variable objects in a computing application and checks if all variable names entered by the user have been declared.
        Returns:
        an ArrayList containing a properly scanned version of the string such that all recognized number substrings,variable substrings and operator substrings have been resolved. To use this method as a scanner for math expressions all the programmer has to do is to take care of the signs where need be(e.g in -2.873*5R+sinh34.2, the scanned view will be [-,2.873,*,5,R,+,sinh,34.2]) To make sense of this, the programmer has to write minor code to concatenate the - and the 2.873 and so on.

      • scanner

        public java.util.ArrayList<java.lang.String> scanner​(VariableManager varMan)
        Utility method,more popularly used as a scanner into mathematical tokens of mathematical expressions
        Parameters:
        varMan - The store of all user variables already declared. The scanner will not allow the user to use any variables he/she/it has not declared
        Returns:
        an ArrayList containing a properly scanned version of the string such that all recognized number substrings,variable substrings and operator substrings have been resolved. To use this method as a scanner for math expressions all the programmer has to do is to take care of the signs where need be(e.g in -2.873*5R+sinh34.2, the scanned view will be [-,2.873,*,5,R,+,sinh,34.2]) To make sense of this, the programmer has to write minor code to concatenate the - and the 2.873 and so on.

      • recognizeAnonymousFunctions

        public static void recognizeAnonymousFunctions​(java.util.List<java.lang.String> scanner)

      • $removeExcessBrackets

        public static void $removeExcessBrackets​(java.util.List<java.lang.String> scanner)
        This technique conserves the last single bracket as it is unsure of the rules that allow it to unwrap the last bracket.
        Parameters:
        scanner - The tokens list

      • removeExcessBrackets

        public static void removeExcessBrackets​(java.util.List<java.lang.String> scanner)
        This technique will rid tokens of offending brackets up to the last bracket. It assumes that it knows the rules that allow one to remove all brackets from a token. One however needs check the ruls to be sure that there is no error. If this one messes up, please switch to the $removeExcessBrackets(List) method.
        Parameters:
        scanner - The list of scanned tokens.

      • extractFunctionStringFromExpressionForMatrixMethods

        public static void extractFunctionStringFromExpressionForMatrixMethods​(java.util.List<java.lang.String> list)
        Analyzes the list and extracts the Function string from it.
        Parameters:
        list - The list to be analyzed. Direct examples would be: intg(@sin(x+1),4,7) intg(F,4,7) where F is a function that has been defined before in the workspace.. and so on. Simplifies the list to the form matrix_method(funcName,params)

      • main

        public static void main​(java.lang.String[] args)
        Parameters:
        args - Command line args (((2+3)^2))!-------((25))!-------