[function] CodeConverter

[Yixx]

CodeConverter

What is CodeConverter?
CodeConverter is a function which can convert any x-base code into an y-base code. Confusing? I shall explain.
Our normal number system is a 10-base code, meaning it has 10 different characters (0,1,2,3,4,5,6,7,8,9,0). When you think about numbers, you think them in a 10-base number normally, but when a computer thinks, he thinks in a 2-base number, binary code.
This function can convert an x-base number into an y-base number, with for x and y any number higher than 1.

The code

Code

library CodeConverter
    function ConvertCode takes integer amount, integer oldbase, integer newbase returns integer
        local integer i = 0
        local integer i2 = 0
        local integer current = 0
        local string amounts = I2S(amount)
        local integer length = StringLength(amounts)
        local string c
        local integer plus = StringLength(I2S(oldbase))
        
        // no x-base or y-base number can be made when x or y are below 2
        if oldbase < 2 or newbase < 2 then
            return -1
        endif
        
        // Why would you want to convert to the same base?
        if oldbase == newbase then
            return amount
        endif
        
        // First we convert to 10-base. But if the old base is already 10, there is no need.
        if oldbase != 10 then
            loop
                set c = SubString(amounts,length-plus-(i*plus),length-(i*plus))
                exitwhen c == "" or length-i == 0
                set current = current + (S2I(c)*R2I(Pow(oldbase,i)))
                set i = i + 1
            endloop
            set i = 0
        endif
        
        // Now we convert to y-base, but if y is 10, we dont need to, because we already did that above.
        if newbase != 10 then
            set c = ""
            loop
                exitwhen Pow(newbase,i) > current
                set i = i + 1
            endloop
            set i = i - 1
            loop
                exitwhen i < 0
                if current >= Pow(newbase,i) then
                    loop
                        exitwhen current < Pow(newbase,i)
                        set i2 = i2 + 1
                        set current = current - R2I(Pow(newbase,i))
                    endloop
                endif
                set c = c + I2S(i2)
                set i2 = 0
                set i = i - 1
            endloop
            return S2I(c)
        else
            return current
        endif
        return -1
    endfunction
endlibrary

A question to you:
What will actually happen when I insert a negative number? Currently it will return the converted number, only positive. should it return negative or positive?

Confession
This can probably be done alot easier without converting to 10-base first, but I do not have the knowledge how to.

-Yixx,,-

 

[Nestharus]

This doesn't necessarily convert from any base to any base. If it did, it'd take 3 strings : ).

string- value
string- old base (each character of that base)
string- new base (each char of that base)

 

[Yixx]

How is making it take a string logical?
And i think the current oldbase/newbase thing (where they are max+1) is good, it is an understandable form this way, and quite logic i think..

call ConvertCode(10110101,2,10)

converts 10110101 from binary code into our numerical system..

Also, how do you think that it doesnt necessarily convert from any base to any base?

 

[Nestharus]

What if you had a base of 2 but with different chars?

What if you had a base of 80? How do you know the characters??


Base conversion is traditionally done in JASS with strings for a reason.

 

[Yixx]

This function on it's own is not meant for your own codes, but with a wrapper function you can create your own, which I did actually..
Using StringTable..

globals
    private StringTable ST
    private integer MaxAmount = 24
    private integer IntPerChar = StringLength(I2S(MaxAmount))
endglobals
function ConvertYOURCODEto10 takes string code returns integer
    local integer l = StringLength(code)
    local integer i = 0
    local string c
    local string input
    loop
        set c = SubString(code,length-IntPerChar-(IntPerChar*i),length-plus)
        exitwhen c == "" or length-plus <=0
        set input = I2S(ST[c]) + input
        set i = i + 1
    endloop
    return ConvertCode(S2I(input),MaxAmount,10)
endfunction

That is how it will look, where you input what value each character of your code has in the StringTable like this:

function Init takes nothing returns nothing
    set ST["A"]=0
    set ST["B"]=1
    // etc..
endfunction

Should I add this in a textmacro or such with the system?

 

[Nestharus]

That is awful ><

Make it dynamic without any setup... just be able to pass in any arbitrary keys (bases) and any arbitrary number

str Convert(str val, str base1, str base2) {
    return value
}

 

[YourNameHere]

Like this?

Hidden

library_once Convert
{
    public constant string DEC = "0123456789"
    public constant string HEX = "0123456789ABCDEF"
    public constant string BIN = "01"
    public constant string OCT = "01234567"
    
    #define
    {
        <Convert_DECIMAL>      = Convert_DEC
        <Convert_HEXADECIMAL>  = Convert_HEX
        <Convert_BINARY>       = Convert_BIN
        <Convert_OCTAL>        = Convert_OCT
    }

    #include "cj_types_private.j"

    //Returns the position where a string is inside another string.
    private int IndexOf(string base, string find)
    {
        int result = 0;
        int length = StringLength(base);
        int flength = StringLength(find);
        
        if length > flength
        {
            do
            {
                if SubString(base, result, result+flength) == find {return result}
            } whilenot(++result > length)
        }
        
        return -1;
    }
    
    string Convert(string num, string from, string to)
    {
        string result = "";
        
        int fl = StringLength(from); //From length
        int tl = StringLength(to); //To length
        
        string nf = SubString(from, 0, 1) //First character from
        string div = "";
        
        int resultmod = 0;
        int resultdiv = 0;
        int i = 0
        
        do
        {
            i = 0;
            resultmod = IndexOf(from, SubString(num, 0, 1));
            div = "";
            
            do
            {
                if resultmod >= tl
                {
                    resultdiv = resultmod/tl;
                    div = div+SubString(from, resultdiv, resultdiv+1);
                    resultmod -= resultdiv*tl;
                }
                else
                {
                    div = div+nf;
                }
                
                exitwhen(++i >= StringLength(num))
                resultmod = (resultmod*fl)+IndexOf(from, SubString(num, i, i+1));
            }
            
            i = 0;
            do
            {
                exitwhen(SubString(div, i, i+1) != nf)
            } whilenot(++i >= StringLength(div))
            
            div = SubString(div, i, StringLength(div));
            result = SubString(to, resultmod, resultmod+1)+result;
            num = div;
            
            exitwhen num == ""
        }
        
        return result;
    }
}

 

[Nestharus]

Like that, but that can def be optimized ; ).

 

[YourNameHere]

I didn't write that actually, I had an pretty old version of that and just parsed it.

 

[maskedpoptart]

Yixxy, this library may be of interest to you; take a look at the IBase2S and SBase2I functions. I'm not sure if they work with negative numbers though.

 

[TriggerHappy]

You should probably split the functions up, to increase efficiency.

ConverToBase.
ConvertFromBase.

Storing the already converted inputs into a hashtable would also help a little.
You may want to take a look at this for reference.

 

[azlier]

Graveyarded due to a month or so of neglect on the part of the author.