Hex and Bin conversion.

[Justin_]

Nothing special, but my first submission

Will continue to update and add more features to the class as I think of them and as I learn more about c++.

comments are welcome. (if i'm doing something bad let me know.)
hex.h

c++:

#include <string> #include <iostream> class Hex {    private:       std::string hexNumber;       int decNumber;    public:       Hex(std::string hNum): hexNumber(hNum)       {}       Hex(int dNum): decNumber(dNum)       {}       ~Hex();       int toInt();       std::string toBin();       std::string toHex(); };

hex.cpp

c++:

#include <iostream> #include <string> #include <sstream> #include "hex.h"                        //constructor Hex::~Hex()           //destructor { } int Hex::toInt() {     int num;     std::stringstream toBeConverted(hexNumber);     toBeConverted >> std::hex >> num;     return num; } std::string Hex::toBin() {    std::string binaryNum;    std::transform(hexNumber.begin(),hexNumber.end(),hexNumber.begin(),tolower);    for (int i = 0; i <= hexNumber.length() ; i++)    {       if (hexNumber.substr(i,1) == "0")          binaryNum  += "0";       if (hexNumber.substr(i,1) == "1")          binaryNum  += "1";       if (hexNumber.substr(i,1) == "2")          binaryNum  += "10";       if (hexNumber.substr(i,1) == "3")          binaryNum  += "11";       if (hexNumber.substr(i,1) == "4")          binaryNum  += "100";       if (hexNumber.substr(i,1) == "5")          binaryNum  += "101";       if (hexNumber.substr(i,1) == "6")          binaryNum  += "110";       if (hexNumber.substr(i,1) == "7")          binaryNum  += "111";       if (hexNumber.substr(i,1) == "8")          binaryNum  += "1000";       if (hexNumber.substr(i,1) == "9")          binaryNum  += "1001";       if (hexNumber.substr(i,1) == "a")          binaryNum  += "1010";       if (hexNumber.substr(i,1) == "b")          binaryNum  += "1011";       if (hexNumber.substr(i,1) == "c")          binaryNum  += "1100";       if (hexNumber.substr(i,1) == "d")          binaryNum  += "1101";       if (hexNumber.substr(i,1) == "e")          binaryNum  += "1110";       if (hexNumber.substr(i,1) == "f")          binaryNum  += "1111";    }    return binaryNum; } std::string Hex::toHex() {    std::stringstream hexNum;    hexNum << std::hex << decNumber;    hexNum >> hexNumber;    return hexNumber; }

Example:

c++:

#include <iostream> #include <string> #include "hex.h" int main () {     Hex number(255);     std::cout << number.toHex() << "\n";     std::cout << number.toInt() << "\n";     std::cout << number.toBin() << "\n";     return 0; }

[md]

Your to binary function definitely doesn't work

And why is this a class? It's much better written as a couple of functions...

[Justin_]

how doesn't it work? And in the near future you'll see why its in a class

[wtd]

Wow... that binary conversion function is excruciatingly complex for no good reason. Now, I won't give you the code outright in C++, but I will show it to you in O'Caml.

code:

let rec to_bin =   function   | 0 -> ""   | n -> to_bin (n / 2) ^ string_of_int (n mod 2)

[Justin_]

It wasn't hard to make, just tedious. I hate repetition but a solid algorithm wasn't coming to mind immediately so I decided to do it the obvious way. Of course, that function only took less than ten minutes to make because I copied and pasted the first line and just filled in all the rest with the appropriate numbers.
For enrichment purposes I will likely design my own algorithm to make it sweeter.

[Justin_]

Cornflake wrote:

Your to binary function definitely doesn't work

I believe you are definitely wrong. I'm adding an updated version anyway, but please note I haven't changed the toBin() function.

[md]

Here's why it doesn't work: 0x00 is 2#00000000. Your code makes it 2#00.

a hex digit is always 4 digits of binary. Strange how wtd missed that one...

[rizzix]

Cornflake wrote:

a hex digit is always 4 digits of binary. Strange how wtd missed that one...

Not really. Well what you are talking about is bits/bytes in memory (hardware stuff). He's talking about the binary number system (math, not hardware).

[Justin_]

a hex digit can be represented with 4 digits of binary true, but a binary digit isn't always four digits. For instance: 0 in binary is 0 in decimal.

I can see what you are saying though, considering I used hex to convert to binary. It's just that converting from hex to binary is much easier than converting decimal to binary. If I knew of an easier way I would have used it.

[avok23]

md @ Thu Feb 16, 2006 12:13 am wrote:

Your to binary function definitely doesn't work

And why is this a class? It's much better written as a couple of functions...

i think he was trying to create an interface like the type you get in managed languages c# and java

Math.Sin( angle ); just in case u have a function with that name. i would probably use a namespace instead