Base converter libary

This is a discussion on Base converter libary within the C++ Programming forums, part of the General Programming Boards category; Im trying to convert a number to a different base. Does anyone know what library has the converter in it. ...

  1. #1
    Registered User cdonlan's Avatar
    Join Date
    Sep 2004
    Posts
    49

    Base converter library

    Im trying to convert a number to a different base. Does anyone know what library has the converter in it.

    Thanks
    Last edited by cdonlan; 01-17-2005 at 04:07 PM.

  2. #2
    UT2004 Addict Kleid-0's Avatar
    Join Date
    Dec 2004
    Posts
    656
    It took a long time! But I got it!! I've got the golden ticket! It took some testing, but now it's bake-ready! It's for C, but of course you could compile this in C++. And no negative comments plz, I took awhile peicing this together.
    Code:
    #include <stdio.h>
    #include <string.h>
    #include <ctype.h>
    #include <math.h>
    
    #define  MAXREAL  1e40
    
    int   ba,bd;
    char  x[40],y[40];
    float r;
    
    enum bool {
     TRUE, FALSE
    };
    
    char *strrev(const char *s) {
     int i=0, len=strlen(s);
    
     char *str = NULL;
     if ((str=malloc(strlen(s)+1)) == NULL) {/*cannot allocate memory */
      return NULL;
     }
    
     while(len)
      str[i++]=s[--len];
     str[i] = '\0';
     return (str);
    }
    
    // Convert a number from base b to base 10. The function returns
    // FALSE if b not in [2..36] or if string x contains invalid
    // characters in base b or if result y is too big.
    enum bool DecodeBase(char *x,int b, float *y) {
     int lgth,i,j;
     float mult; char *ch;
     if (b<2 || b>36) {
      printf(" Base must be between 2 and 36 !\n");
      return FALSE;
     }
     *y=0; mult=1.0;
     lgth=strlen(x);
     for (i=0; i<lgth; i++) {
      ch=&x[lgth-i-1];
      if (!isalnum(ch[0])) {
      printf(" Error in input number.\n");
      return FALSE;
      }
      if (*ch<='9')
      j=toupper(*ch)-'0';
      else
       j=toupper(*ch)-'A'+10;
      if (j>=b) return FALSE;
      *y+=mult*j;
      if (mult>MAXREAL/b) return FALSE;
      mult=mult*b;
     }
     return TRUE;
    }
    
    //Convert a number from base 10 to base b. The function returns
    //FALSE if b not in [2..36] or if string x contains invalid
    //characters in base 10 or if number x is too big.
    enum bool CodeBase(float x,int b, char *y) {
     int n; char ch[2];
     if (b<2 || b>36) {
      printf(" Base must be between 2 and 36 !\n");
      return FALSE;
     }
     strcpy(y, "");
     while (x>0) {
      n=(int) floor(x - b * (int)(x/b));
      if (n<10) {
       //y=Chr(Ord("0")+n)+y;
       sprintf(ch,"%d",n);
      strcat(y,ch);
      }
      else {
       //y=Chr(Ord("A")+n-10) +y;
       switch(n) {
       case 10: strcat(y,"A"); break;
       case 11: strcat(y,"B"); break;
       case 12: strcat(y,"C"); break;
       case 13: strcat(y,"D"); break;
       case 14: strcat(y,"E"); break;
       case 15: strcat(y,"F"); break;
       case 16: strcat(y,"G"); break;
       case 17: strcat(y,"H"); break;
       case 18: strcat(y,"I"); break;
       case 19: strcat(y,"J"); break;
       case 20: strcat(y,"K"); break;
       case 21: strcat(y,"L"); break;
       case 22: strcat(y,"M"); break;
       case 23: strcat(y,"N"); break;
       case 24: strcat(y,"O"); break;
       case 25: strcat(y,"P"); break;
       case 26: strcat(y,"Q"); break;
       case 27: strcat(y,"R"); break;
       case 28: strcat(y,"S"); break;
       case 29: strcat(y,"T"); break;
       case 30: strcat(y,"U"); break;
       case 31: strcat(y,"V"); break;
       case 32: strcat(y,"W"); break;
       case 33: strcat(y,"X"); break;
       case 34: strcat(y,"Y"); break;
       case 35: strcat(y,"Z");
      }
      }
      x=(float) (int)(x/b);
     }
     y=strrev(y); //string inversion
     return TRUE;
    }
    
    int main(void)  {
    
     int theBaseIWant = 2;
     int theNumber = 40;
     char Output[255];
    
     // From base 10 -> 2
     if(CodeBase(theNumber, theBaseIWant, Output) == TRUE) {
      puts(Output);
     }
     else {
      puts("WWWHHYY!!");
      return 0;
     }
    
     // From Base 16(Hex) --> Base 2(Binary)
     float decimal;
     char Input[] = "00FF";
     if(DecodeBase(Input, 16, &decimal) == FALSE) {
      puts("WWWHHYY!!");
      return 0;
     }
    
     if(CodeBase(decimal, 2, Output) == FALSE) {
      puts("WWWHHYY!!");
      return 0;
     }
    
     printf("Our decimal: %.2f\n", decimal);
    
     /* Tested the strrev() function
     char *myWord = "Hello World";
     char WordBackwards[strlen(myWord)+1];
    
     if(strrev(myWord) != NULL) {
      strcpy(WordBackwards, strrev(myWord));
      puts(WordBackwards);
     }
     else {
      puts("AAHH!!");
     }*/
    
     /* Original source
     printf("\n BASE CONVERSION\n\n");
     printf(" Start  Base (2 to 36): "); scanf("%d",&bd);
     printf(" Arival Base (2 to 36): "); scanf("%d",&ba);
     strcpy(x,"1");
     while (strcmp(x,"0")!=0) {
      printf("\n Enter number in start base: "); scanf("%s",x);
      if (strcmp(x,"0")!=0) {
       if (DecodeBase(x,bd,&r)) {
       if (CodeBase(r,ba,y))
        printf(" In base %d:  %s\n",ba,y);
       else
        printf(" Error in coding number.\n");
       }
       else
       printf(" Error in decoding number.\n");
      }
     }
     printf("\n\n");*/
    
     return 0;
    }

  3. #3
    Registered User cdonlan's Avatar
    Join Date
    Sep 2004
    Posts
    49
    If I only need bases 3 ,5,7, and 9. And the largest the number could go up to is 1,000,000 I could cut out a lot of that stuff In the 10 to b-base function.

  4. #4
    UT2004 Addict Kleid-0's Avatar
    Join Date
    Dec 2004
    Posts
    656
    Well you probably could, it was made to work with base-2 through base-30 I believe.

  5. #5
    Registered User cdonlan's Avatar
    Join Date
    Sep 2004
    Posts
    49
    For some reason it does not like the strrev function. I included all the header files.

  6. #6
    Slave MadCow257's Avatar
    Join Date
    Jan 2005
    Posts
    735
    then use my code
    it converts base 10 to any base (2-36)
    I just threw it together, but it works fine I think.
    Code:
    #include <iostream>
    #include <string.h>
    
    using namespace std;
    
    int main()
    {
    	string output;
    	int input, base, counter=0;
    	cout << "Please input the number to be converted: ";
    	cin >> input;
    	cout << "Please input the base to convert to: ";
    	cin >> base;
    	while (input != 0)
    	{
    		switch (input % base)
    		{
    		case 0:
    			output += '0';
    			break;
    		case 1:
    			output += '1';
    			break;
    		case 2:
    			output += '2';
    			break;
    		case 3:
    			output += '3';
    			break;
    		case 4:
    			output += '4';
    			break;
    		case 5:
    			output += '5';
    			break;
    		case 6:
    			output += '6';
    			break;
    		case 7:
    			output += '7';
    			break;
    		case 8:
    			output += '8';
    			break;
    		case 9:
    			output += '9';
    			break;
    		case 10:
    			output += 'A';
    			break;
    		case 11:
    			output += 'B';
    			break;
    		case 12:
    			output += 'C';
    			break;
    		case 13:
    			output += 'D';
    			break;
    		case 14:
    			output += 'E';
    			break;
    		case 15:
    			output += 'F';
    			break;
    		case 16:
    			output += 'G';
    			break;
    		case 17:
    			output += 'H';
    			break;
    		case 18:
    			output += 'I';
    			break;
    		case 19:
    			output += 'J';
    			break;
    		case 20:
    			output += 'J';
    			break;
    		case 21:
    			output += 'K';
    			break;
    		case 22:
    			output += 'L';
    			break;
    		case 23:
    			output += 'M';
    			break;
    		case 24:
    			output += 'N';
    			break;
    		case 25:
    			output += 'O';
    			break;
    		case 26:
    			output += 'P';
    			break;
    		case 27:
    			output += 'Q';
    			break;
    		case 28:
    			output += 'R';
    			break;
    		case 29:
    			output += 'S';
    			break;
    		case 30:
    			output += 'T';
    			break;
    		case 31:
    			output += 'U';
    			break;
    		case 32:
    			output += 'V';
    			break;
    		case 33:
    			output += 'W';
    			break;
    		case 34:
    			output += 'X';
    			break;
    		case 35:
    			output += 'Y';
    			break;
    		case 36:
    			output += 'Z';
    			break;
    		}
    		input = input/base;
    		counter++;
    	}
    	cout << "The result of the conversion is ";
    	while (counter > -1)
    	{
    		cout << output[counter];
    		counter--;
    	}
    	cout << "\n";
    	return 0;
    }

  7. #7
    Registered User cdonlan's Avatar
    Join Date
    Sep 2004
    Posts
    49
    Thanks a lot guys

  8. #8
    UT2004 Addict Kleid-0's Avatar
    Join Date
    Dec 2004
    Posts
    656
    Quote Originally Posted by cdonlan
    For some reason it does not like the strrev function. I included all the header files.
    What's the error code? It works fine for me. strrev() is also inside <windows.h>, so beware. You may want to rename strrev to strrev2 just so there aren't any conflicting methods. Good luck!

    Nice function MadCow

  9. #9
    C Programmer Stack Overflow's Avatar
    Join Date
    Apr 2004
    Posts
    477
    Well,

    Since this is the C++ section, and not C, strrev() would not be the first to choose from. strrev() is not within the C++ standard. Though, there is another function that is within the C++ standard library called reverse_copy().

    Looking closer at Kleid-0's code, I see that he passes a character array that holds 255 characters to CodeBase(). Though when he handles it, he passes that function to strrev() which allocates memory to it. Just an observation.

    Even though strrev() isn't standard, it could be done simply by using the XOR method:
    Code:
    char* strrev(char *str) {
    	char *p1, *p2;
    
    	if (!str || !*str)
    		return str;
    
    	for (p1 = str, p2 = str + strlen(str) - 1; p2 > p1; ++p1, --p2) {
    		*p1 ^= *p2;
    		*p2 ^= *p1;
    		*p1 ^= *p2;
    	}
    
    	return str;
    }
    All in all, I don't see a need to use a C-style function in C++.


    - Stack Overflow
    Segmentation Fault: I am an error in which a running program attempts to access memory not allocated to it and core dumps with a segmentation violation error. This is often caused by improper usage of pointers, attempts to access a non-existent or read-only physical memory address, re-use of memory if freed within the same scope, de-referencing a null pointer, or (in C) inadvertently using a non-pointer variable as a pointer.

  10. #10
    Handy Andy andyhunter's Avatar
    Join Date
    Dec 2004
    Posts
    540
    Kleid-0, you need to take a break pal. Go get laid or drunk or both.
    i don't think most standard compilers support programmers with more than 4 red boxes - Misplaced

    It is my sacred duity to stand in the path of the flood of ignorance and blatant stupidity... - quzah

    Such pointless tricks ceased to be interesting or useful when we came down from the trees and started using higher level languages. - Salem

  11. #11
    UT2004 Addict Kleid-0's Avatar
    Join Date
    Dec 2004
    Posts
    656
    YOU JUST BACK OFF ANDY!!! lol, j/k . I deleted that post, I was releasing too much negative energy!

  12. #12
    Hardware Engineer
    Join Date
    Sep 2001
    Posts
    1,398
    strtoul() will convert from any base (2-36) to a standard integer.

    cout can display a number in octal, decimal, or hex, and with a little help from <bitset> you can display in binary.

    There isn't a standard built-in function to convert from a standard integer to any base. But if you have a Microsoft compiler, itoa() will do exactly that.

    Note that any conversion is normally done only during input or output. The above functions convert between an integer and a C-style-string representation of the number in another base.

    All variables in the computer's memory are stored in binary. C++ changes it to decimal input/output by default. This means that you can enter one number in decimal, another in hex, add them together, and display the result in octal, without worrying about the fact that you mixing bases!

    Here's an example program I wrote a couple of years ago:
    Attached Files Attached Files

  13. #13
    Registered User
    Join Date
    Apr 2005
    Posts
    53
    Quote Originally Posted by MadCow257
    then use my code
    it converts base 10 to any base (2-36)
    I just threw it together, but it works fine I think.
    Code:
    #include <iostream>
    #include <string.h>
    
    using namespace std;
    
    int main()
    {
    	string output;
    	int input, base, counter=0;
    	cout << "Please input the number to be converted: ";
    	cin >> input;
    	cout << "Please input the base to convert to: ";
    	cin >> base;
    	while (input != 0)
    	{
    		switch (input % base)
    		{
    		case 0:
    			output += '0';
    			break;
    		case 1:
    			output += '1';
    			break;
    		case 2:
    			output += '2';
    			break;
    		case 3:
    			output += '3';
    			break;
    		case 4:
    			output += '4';
    			break;
    		case 5:
    			output += '5';
    			break;
    		case 6:
    			output += '6';
    			break;
    		case 7:
    			output += '7';
    			break;
    		case 8:
    			output += '8';
    			break;
    		case 9:
    			output += '9';
    			break;
    		case 10:
    			output += 'A';
    			break;
    		case 11:
    			output += 'B';
    			break;
    		case 12:
    			output += 'C';
    			break;
    		case 13:
    			output += 'D';
    			break;
    		case 14:
    			output += 'E';
    			break;
    		case 15:
    			output += 'F';
    			break;
    		case 16:
    			output += 'G';
    			break;
    		case 17:
    			output += 'H';
    			break;
    		case 18:
    			output += 'I';
    			break;
    		case 19:
    			output += 'J';
    			break;
    		case 20:
    			output += 'J';
    			break;
    		case 21:
    			output += 'K';
    			break;
    		case 22:
    			output += 'L';
    			break;
    		case 23:
    			output += 'M';
    			break;
    		case 24:
    			output += 'N';
    			break;
    		case 25:
    			output += 'O';
    			break;
    		case 26:
    			output += 'P';
    			break;
    		case 27:
    			output += 'Q';
    			break;
    		case 28:
    			output += 'R';
    			break;
    		case 29:
    			output += 'S';
    			break;
    		case 30:
    			output += 'T';
    			break;
    		case 31:
    			output += 'U';
    			break;
    		case 32:
    			output += 'V';
    			break;
    		case 33:
    			output += 'W';
    			break;
    		case 34:
    			output += 'X';
    			break;
    		case 35:
    			output += 'Y';
    			break;
    		case 36:
    			output += 'Z';
    			break;
    		}
    		input = input/base;
    		counter++;
    	}
    	cout << "The result of the conversion is ";
    	while (counter > -1)
    	{
    		cout << output[counter];
    		counter--;
    	}
    	cout << "\n";
    	return 0;
    }

    I'm writing a similiar program that also accomplishes a conversion task, but I'm trying to rewrite this so that for a value it would print out all the conversions from base 2 up to base 30. I was wondering what would be the best way to translate it and print out all bases instead of a specific. Thanks.

  14. #14
    He's trying.
    Join Date
    Apr 2005
    Location
    Missouri, US
    Posts
    70
    I made something like this (Decimal to BASE) a couple weeks ago...I'm not so good, but I think this does pretty much what it's supposed to.

    It'll go up to base...36, I think. It doesn't have any case statements!
    Attached Files Attached Files

  15. #15
    Registered User
    Join Date
    Apr 2005
    Posts
    53
    I just took a look at the file, it actually does have case statments. I'm just trying to get a simplified version of the code but being able to take argv[1] and conver it from base 2 up to base 30. Bascially not having to specify the cases. I tried to modifed the other verison that I put up, but I get some weird errors. I'm not sure how they looped through it to actually get the values. Thank you.

Page 1 of 2 12 LastLast
Popular pages Recent additions subscribe to a feed

Similar Threads

  1. Code review
    By Elysia in forum C++ Programming
    Replies: 71
    Last Post: 05-13-2008, 09:42 PM
  2. Base Converter Part 2
    By encyclopedia23 in forum C Programming
    Replies: 2
    Last Post: 12-30-2006, 01:42 PM
  3. Base Converter
    By encyclopedia23 in forum C Programming
    Replies: 3
    Last Post: 12-29-2006, 07:55 AM
  4. Base10 to Base n converter
    By P4r4digm in forum C++ Programming
    Replies: 1
    Last Post: 10-04-2006, 09:34 PM
  5. Help With Libary Data Base.
    By Dangerous Dave in forum C Programming
    Replies: 5
    Last Post: 04-23-2002, 06:21 PM

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21