//Copyright (C) 2004 <Mohammed Azmy> moh286@yahoo.com
/* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* any later version.
*/
using System;
namespace ParserEngine
{
/// <summary>
/// this is a standalone class that has a static method allow the programmer to
/// send a string represent a mathematical expression and get the answer
/// This is my first program in my entire life ,so I think it will be foll of mistakes
/// but at least it work.
/// this class written by MOHAMMED AZMY - Egypt please do not remove this name
/// and I allow you to use this class in any way, editing or using in any program
///
/// You can send to it an equation like this
/// NOTE: IT SOLVE THE EQUATION IN RADIAN.
/// 2+3*4/(5*sin3)+(3*4.54)^2-ln(log3)/10E2-e4+3&8
/// </summary>
public class Parser
{
public static double calculate(string equationtext,ref bool error)
{
/*
* this method will writ the equation in the correct syntax
* which is (any thing+0) to avoid some exception...
* This method will also fix some syntax errors
* like Exponent sign, some logical operation like (2+3)(3+4)
* (suppose to be (2+3)*(3+4) & 2(1+2)--> 2*(1+2)
* and so on...
*/
error=false;
string correctsyntax=equationtext+"+0";
parserstring word=new parserstring(correctsyntax);
/*
* this next loop will search foe exponant like 2E2
* it will insert + sign to be 2E+2
* if 2E-2 it will not do any thing
* this is not so important but it is the only way to
* solve the expetion coused by entering 2*2E2
*/
//this next line related to (-whatever)^2...... go to there.
//if (word.wordarray[0].ToString()=="(")word=word.insert("0+",0);
for (int loop=1;loop<word.length-1;loop++)
{
string what=word.wordarray[loop].ToString();
string whatfor=word.wordarray[loop-1].ToString();
string whataf=word.wordarray[loop+1].ToString();
if (what=="E")
{
if (what!="-")
{
word=word.insert("+",loop+1);
}
}
if (what=="("&&whatfor==")")
{
word=word.insert("*",loop);
}
if (what=="("&&whatfor==".")word=word.insert("*",loop);
if (what=="(")
{
try
{
double whatbefore=double.Parse(whatfor);
word=word.insert("*",loop);
}
catch
{
}
}
if (what==")")
try
{
double whatafter=double.Parse(whataf);
word=word.insert("*",loop+1);
}
catch
{
}
if (what==")"&&whataf==".")word=word.insert("*",loop+1);
}
try
{
return bracket(word);
}
catch
{
error=true;
return 0;
}
}
private static double bracket(parserstring word)
{
bool dumy=false;
int start=0;
string what;
double result=0;
string tocalculate;
string xwhat;
//int nextpowerindex;
for (int loop=0;loop<word.length;loop++)
{
if (word.wordarray[loop].ToString()=="E")loop+=2;
what=word.wordarray[loop].ToString();
if (what=="(")start=loop;
if (what==")")
{
tocalculate=word.copy(start+1,loop);
result=calculate(tocalculate,ref dumy);
if (word.wordarray[loop+1].ToString()=="^")
{
for (int xloop=loop+3;loop<word.length;xloop++)
{
if (word.wordarray[xloop].ToString()=="E")xloop+=2;
xwhat=word.wordarray[xloop].ToString();
if (xwhat=="+"||xwhat=="-"||xwhat=="*"||xwhat=="/"||xwhat=="^")
{
string powerpart=word.copy(loop+1,xloop);
result=compiler(new parserstring(result.ToString()+powerpart));
word=word.replace("("+result.ToString()+")",start,xloop);
break;
}
}
}
else
{
word=word.replace(result.ToString(),start,loop+1);
}
return bracket(word);
}
}
return advancedfn(word);
//return calculate(word.ParseToString(word));
}
private static double advancedfn(parserstring word)
{
/*
* this method will solve the advanced fn
* sin cos tan Asin Acos Atan sinh cosh tanh log & ln
*/
string ch_2;
string ch_3;
string ch_4;
int nextop=0;
string tocalculate;
double result=0;
string what;
for (int loop=0;loop<word.length;loop++)
{
if (word.wordarray[loop].ToString()=="E")loop+=2;
//replacing the constant e
if (word.wordarray[loop].ToString()=="e")
{
if (word.wordarray[loop+1].ToString()=="*"||word.wordarray[loop+1].ToString()=="/"||word.wordarray[loop+1].ToString()=="^"||word.wordarray[loop+1].ToString()=="&")
{
word=word.replace(Math.E.ToString(),loop,loop+1);
}
else
{
word=word.replace(Math.E.ToString()+"^",loop,loop+1);
}
return advancedfn(word);
}
//solving factorial
if (word.wordarray[loop].ToString()=="!")
{
for (int xloop=loop;xloop>=0;xloop--)
{
what=word.wordarray[xloop].ToString();
if (what=="+"||what=="-"||what=="*"||what=="/"||what=="^"||what=="&")
{
nextop=xloop;
break;
}
if (xloop==0)
{
nextop=xloop-1;
}
}
tocalculate=word.copy(nextop+1,loop);
result=Fact(int.Parse(tocalculate));
word=word.replace(result.ToString(),nextop+1,loop+1);
return advancedfn(word);
}
//preparing to solve the fn.
if(loop>=word.length-3)break;
ch_2=word.wordarray[loop].ToString()+word.wordarray[loop+1].ToString();
ch_3=ch_2+word.wordarray[loop+2].ToString();
ch_4=ch_3+word.wordarray[loop+3].ToString();
//replacing the constant pi
if (ch_2=="pi")
{
word=word.replace(Math.PI.ToString(),loop,loop+2);
return advancedfn(word);
}
//checking for ln
if (ch_2=="ln")
{
for (int xloop=loop+3;xloop<word.length;xloop++)
{
what=word.wordarray[xloop].ToString();
if (what=="+"||what=="-"||what=="*"||what=="/"||what=="^"||what=="&")
{
nextop=xloop;
break;
}
}
tocalculate=word.copy(loop+2,nextop);
result=Math.Log(double.Parse(tocalculate),Math.E);
word=word.replace(result.ToString(),loop,nextop);
ch_2="";
return advancedfn(word);
}
//checking for "Asin ,Acos ,Atan ,sinh ,cosh ,tanh "
if (ch_4=="Asin"||ch_4=="Acos"||ch_4=="Atan"||ch_4=="sinh"||ch_4=="cosh"||ch_4=="tanh")
{
for (int xloop=loop+5;xloop<word.length;xloop++)
{
what=word.wordarray[xloop].ToString();
if (what=="+"||what=="-"||what=="*"||what=="/"||what=="^"||what=="&")
{
nextop=xloop;
break;
}
}
tocalculate=word.copy(loop+4,nextop);
//tocalculate=(advancedfn(new parserstring(tocalculate))).ToString();
switch (ch_4)
{
case "Asin":
result=Math.Asin(double.Parse(tocalculate));
break;
case "Acos":
result=Math.Acos(double.Parse(tocalculate));
break;
case "Atan":
result=Math.Atan(double.Parse(tocalculate));
break;
case "sinh":
result=Math.Sinh(double.Parse(tocalculate));
break;
case "cosh":
result=Math.Cosh(double.Parse(tocalculate));
break;
case "tanh":
result=Math.Tanh(double.Parse(tocalculate));
break;
}
word=word.replace(result.ToString(),loop,nextop);
ch_4="";
return advancedfn(word);
}
//checking for "log , sin ,cos ,tan"
if (ch_3=="log"||ch_3=="sin"||ch_3=="cos"||ch_3=="tan")
{
for (int xloop=loop+4;xloop<word.length;xloop++)
{
what=word.wordarray[xloop].ToString();
if (what=="+"||what=="-"||what=="*"||what=="/"||what=="^"||what=="&")
{
nextop=xloop;
break;
}
}
tocalculate=word.copy(loop+3,nextop);
//tocalculate=(advancedfn(new parserstring(tocalculate))).ToString();
switch (ch_3)
{
case "log":
result=Math.Log(double.Parse(tocalculate),10);
break;
case "sin":
result=Math.Sin(double.Parse(tocalculate));
break;
case "cos":
result=Math.Cos(double.Parse(tocalculate));
break;
case "tan":
result=Math.Tan(double.Parse(tocalculate));
break;
}
word=word.replace(result.ToString(),loop,nextop);
ch_3="";
return advancedfn(word);
}
}
return power(word);
}
private static double power(parserstring word)
{
/*
* this method solve the power
* like 2^3 or 2√4 i.e sqrt(4) or any other root like
* 3√8 (the 3rd root of 8)
*
*/
int lastindex=-1;
//int powerindex;
bool poweron=false;
string what;
for (int loop=0;loop<word.length;loop++)
{
if (word.wordarray[loop].ToString()=="E")loop+=2;
what=word.wordarray[loop].ToString();
if (what=="+"||what=="-"||what=="*"||what=="/"||what=="^"||what=="&")
{
if (poweron==true)
{
/*if (word.wordarray[lastindex-1].ToString()=="+"||word.wordarray[lastindex-1].ToString()=="-"||
word.wordarray[lastindex-1].ToString()=="*"||word.wordarray[lastindex-1].ToString()=="/")lastindex--;
*/
string tocompiler=word.copy(lastindex+1,loop);
double back=(compiler(new parserstring(tocompiler)));
word=word.replace(back.ToString(),lastindex+1,loop);
return power(word);
}
else
{
if(what!="^"&&what!="&")lastindex=loop;
/*if (lastindex!=0)
{
if (what=="-"&&(word.wordarray[loop-1].ToString()=="+"||word.wordarray[loop-1].ToString()=="-"||word.wordarray[loop-1].ToString()=="*"||word.wordarray[loop-1].ToString()=="/"))lastindex--;
}*/
}
}
if (what=="^"||what=="&")
{
poweron=true;
if (word.wordarray[loop+1].ToString()=="+"||word.wordarray[loop+1].ToString()=="-")
{
loop+=2;
}
//powerindex=loop;
}
}
return calculator(word);
}
private static double calculator(parserstring word)
{
/*
* Finally it works.
* I donn't know how to describe how this method work.
*
*/
bool multon=false;
int firstsumpoint=-1;
for (int loop=1;loop<word.length;loop++)
{
if (word.wordarray[loop].ToString()=="E")loop+=2;
if (word.wordarray[loop].ToString()=="*" || word.wordarray[loop].ToString()=="/")
{
// I think this can be improved...........HERE
multon=true;
//loop++;
if (word.wordarray[loop+1].ToString()=="+" || word.wordarray[loop+1].ToString()=="-")
{
loop+=2;
}
else
{
loop++;
}
}
if ((word.wordarray[loop].ToString()=="+" || word.wordarray[loop].ToString()=="-")&& multon==true)
{
string tomultiplier=word.copy(firstsumpoint+1,loop);
string multres=(multiplier(new parserstring(tomultiplier))).ToString();
word=word.replace(multres,firstsumpoint+1,loop);
return calculator(word);
}
if ((word.wordarray[loop].ToString()=="+" || word.wordarray[loop].ToString()=="-")&& multon==false)
{
firstsumpoint=loop;
}
}
return adder(word);
}
private static double multiplier(parserstring word)
{
/*
* this method receive an word contain alot af mult. or division
* values like 5*6/3*2 and return the result as a double
*/
bool multon=false;
for (int loop=1;loop<word.length;loop++)
{
if (word.wordarray[loop].ToString()=="E")loop+=2;
if (word.wordarray[loop].ToString()=="*" ||word.wordarray[loop].ToString()=="/")
{
if (multon==true)
{
string tocompile=word.copy(0,loop);
string compilerRes=(compiler(new parserstring(tocompile))).ToString();
word=word.replace(compilerRes,0,loop);
multon=false;
return multiplier(word);
}
else
{
multon=true;
loop++;
/*
* I make loop+=1 to solve the exception coused by typing
* *- or /+ like 1*-3 this will equal -2;
*/
}
}
}
return compiler(word);
}
private static double adder(parserstring word)
{
/*
* this method receive an word contain alot af added or subtracted
* values like 5+2+-3-6 and return the res as a double
*/
bool sumon=false;
for (int loop=1;loop<word.length;loop++)
{
if (word.wordarray[loop].ToString()=="E")loop+=2;
if (word.wordarray[loop].ToString()=="+" ||word.wordarray[loop].ToString()=="-")
{
if (sumon==true)
{
string tocompile=word.copy(0,loop);
string compilerRes=(compiler(new parserstring(tocompile))).ToString();
word=word.replace(compilerRes,0,loop);
sumon=false;
return adder(word);
}
else
{
sumon=true;
loop++;
/*
* I make loop+=1 to solve the exception coused by typing
* +- or -+ like 1+-3 this will equal -2;
*/
}
}
}
return compiler(word);
/*if (sumon==true)
{
return compiler(word);
}
else
{
return double.Parse(word.copy(0,word.length));
}*/
}
private static double compiler(parserstring word)
{
/*
* this methode execute a simple operation like No1+No2 or N01/No2
* and so on. by basing an parserstring array contain this eq.
* The loop begains from the second element in the array to avoid
* considering the -ve or +ve sign as an operation.
*/
string result=word.ParseToString();
double res=0;
for (int loop=1;loop<word.length;loop++)
{
if (word.wordarray[loop].ToString()=="E")loop+=2;
if (word.wordarray[loop].ToString()=="+" ||word.wordarray[loop].ToString()=="-" ||word.wordarray[loop].ToString()=="*" ||word.wordarray[loop].ToString()=="/"||word.wordarray[loop].ToString()=="^"||word.wordarray[loop].ToString()=="&")
{
int index=loop;
//double result;
string value1=word.copy(0,loop);
string value2=word.copy(loop+1,word.length);
double no1=double.Parse(value1);
double no2=double.Parse(value2);
switch (word.wordarray[loop].ToString())
{
case "+":
res=(no1+no2);
break;
case "-":
res=(no1-no2);
break;
case "*":
res=(no1*no2);
break;
case "/":
res=(no1/no2);
break;
case "^":
res=Math.Pow(no1,no2);
break;
case "&":
res=Math.Pow(no2,1/no1);
break;
}
break;
}
}
return res;
/*if (res!=0)
{
return res;
}
else
{
return double.Parse(result);
}*/
}
private static int Fact(int x)
{
if (x==0) return 1;
else return x*Fact(x-1);
}
}
class parserstring
{
/*
* this class contain an array of characters treated as a string
* and some methods that do some functions over it like removing
* and replacing and inserting
* the constuctor puts an string into the array
*
*/
public char[] wordarray;
public int length=0;
public parserstring(string word)
{
this.length=word.Length;
wordarray=new char[length];
wordarray=word.ToCharArray(0,length);
}
public string copy(/*from starting with zero*/int start,/*to*/int end)
{
/*
* this static method copy a piece of the parserstring array to an string
*/
string copyed="";
for (int loop=start;loop<end;loop++)
{
copyed=copyed+wordarray[loop];
}
return copyed;
}
public parserstring insert(string whattoinsert,int at)
{
/*
* this method insert a string at an specific index(before it)
*/
string resultstring=copy(0,at);
resultstring+=whattoinsert+copy(at,this.length);
return new parserstring(resultstring);
}
public parserstring replace(string whattoinsert,int from,int to)
{
/*
* this method replace a No. of characters in the array with a string
* from an specified index to another
*
*/
string resultstring=copy(0,from);
resultstring+=whattoinsert+copy(to,this.length);
return new parserstring(resultstring);
}
public string ParseToString()
{
string back="";
foreach (char i in wordarray)
{
back+=i.ToString();
}
return back;
}
}
}
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