Quickly Converting uint32_t to binary - c++

Question

The main problem I'm having is to read out values in binary in C++ (python had some really quick/easy functions to do this)
I just need the same. So at the moment I have:
ValWord< uint32_t> data1=//[SOME READ FUNCTION]
When I use cout << data1; It gives me a number e.g 2147581953
I want this to be in binary and eventually each "bit" needs to be in its own bin including all '0's e.g:
for (int i = 31; i >= 0; i--) {
cout << binary[i];
}
Would give me this 32 bit long binary number. When I've had it as a straight forwward int, I've used:
int data[32];
bitset<32>(N) = data1;
for(int i=31; i >=0; i--) {
data[i]=(bitset<32>(N[i]).to_ulong());
}
for (int i = 31; i >= 0; i--) {
cout << data[i];
}
But this just gives me error messages. Any ideas?

Answer 1

Maybe this:
#define CPlusPlus11 0
#if CPlusPlus11
int main()
{
std::uint32_t value(42);
std::bitset<32> bits(value);
std::cout << bits.to_string() << std::endl;
// Storing integral values in the string:
for(auto i: bits.to_string(char(0), char(1))) {
std::cout << (int)i;
}
std::cout << std::endl;
return 0;
}
#else
int main()
{
std::uint32_t value(42);
std::bitset<32> bits(value);
std::cout << bits.to_string() << std::endl;
char data[32];
for(unsigned i = 0; i < 32; ++i) {
data[i] = bits[i];
}
for(unsigned i = 32; i; --i) {
std::cout << int(data[i-1]);
}
std::cout << std::endl;
return 0;
}
#endif
Note: Your expressions bitset<32>(N) = data1 and bitset<32>(N[i]) are code smell.

Answer 2

In general, transforming a number into a string for a given base, is quite ubiquitous:
#include <cassert>
#include <string>
static char const Digits[] = "0123456789abcdefghijklmnopqrstuvwxyz";
static size_t const DigitsSize = sizeof(Digits) - 1;
static size_t const BufferSize = 32;
std::string convert(unsigned number, unsigned base) {
assert(base >= 2 and base <= DigitsSize);
char buffer[BufferSize] = {};
char* p = buffer + BufferSize;
while (number != 0) {
*(--p) = Digits[number % base];
number /= base;
}
return std::string(p, (buffer + BufferSize) - p);
}
Note: BufferSize was computed for the minimum base of 2, base 1 and base 0 are non-sensical.
Note: if the number can be negative, the simplest is to test for it beforehand, and then use its opposite; a special caveat is that the opposite of the minimum value of a 32 bits integer cannot be represented by a 32 bits integer in base 2.

Answer 3

I have some simple functions i use for this, using stl, here is one for binary:
#include <iostream>
#include <algorithm>
using namespace std;
string binary( unsigned long n )
{
string result;
do result.push_back( '0' + (n & 1) );
while (n >>= 1);
reverse( result.begin(), result.end() );
return result;
}
int main()
{
cout << binary(1024) << endl;
cout << "Hello World" << endl;
return 0;
}
Hope this is of use to you!
Let me know if you need something more performant and I can try to rustle up some Assembler code for you.