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copied!<p>I have written an <a href="https://jonnydee.wordpress.com/2011/05/01/convert-a-block-of-digits-from-base-x-to-base-y" rel="nofollow">article</a> which describes a simple solution in Python which can be used to transfrom a series of numbers from and to arbitrary number bases. I've originally implemented the solution in C, and I didn't want a dependency to an external library. I think you should be able to rewrite the very easy Python code in C or whatever you like.</p> <p>Here is the Python code: </p> <pre><code>import math import string def incNumberByValue(digits, base, value): # The initial overflow is the 'value' to add to the number. overflow = value # Traverse list of digits in reverse order. for i in reversed(xrange(len(digits))): # If there is no overflow we can stop overflow propagation to next higher digit(s). if not overflow: return sum = digits[i] + overflow digits[i] = sum % base overflow = sum / base def multNumberByValue(digits, base, value): overflow = 0 # Traverse list of digits in reverse order. for i in reversed(xrange(len(digits))): tmp = (digits[i] * value) + overflow digits[i] = tmp % base overflow = tmp / base def convertNumber(srcDigits, srcBase, destDigits, destBase): for srcDigit in srcDigits: multNumberByValue(destDigits, destBase, srcBase) incNumberByValue(destDigits, destBase, srcDigit) def withoutLeadingZeros(digits): for i in xrange(len(digits)): if digits[i] != 0: break return digits[i:] def convertNumberExt(srcDigits, srcBase, destBase): # Generate a list of zero's which is long enough to hold the destination number. destDigits = [0] * int(math.ceil(len(srcDigits)*math.log(srcBase)/math.log(destBase))) # Do conversion. convertNumber(srcDigits, srcBase, destDigits, destBase) # Return result (without leading zeros). return withoutLeadingZeros(destDigits) # Example: Convert base 10 to base 16 base10 = [int(c) for c in '1234567890987654321234567890987654321234567890987654321'] base16 = convertNumberExt(base10, 10, 16) # Output list of base 16 digits as HEX string. hexDigits = '0123456789ABCDEF' string.join((hexDigits[n] for n in base16), '') </code></pre>

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