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HTML Settings

Here you can Sed posuere consectetur est at lobortis. Donec ullamcorper nulla non metus auctor fringilla. Maecenas sed diam eget risus varius blandit sit amet non magna. Donec id elit non mi porta gravida at eget metus. Praesent commodo cursus magna, vel scelerisque nisl consectetur et.

            
              <input type="text" id="input" />
<button id="print">Print</button>
<div>
  <br/>
  
  <div>Sign bit: <span id="sign"></span></div>
  <div>Exponent bits: <span id="exponent"></span></div>
  <div>Significant bits: <span id="significant"></span></div>
  <br/>
  <div>Scientific Binary Representation: <span id="output"></span></div>  
</div>
  
  
</div>
            
          
!
            
              document.getElementById('print').addEventListener('click', function() {
  var input = document.getElementById('input'),
      output = document.getElementById('output'),
      exponent = document.getElementById('exponent'),
      significant = document.getElementById('significant'),
      sign = document.getElementById('sign');
  
  var n = parseFloat(input.value);  
  var res = toMathString(n);
  output.innerText = res[0];
  sign.innerText = res[1];
  exponent.innerText = res[2];
  significant.innerText = res[3];
  //console.log(toMathString(n));
});

// assuming BigEndian
/**
 * getting bit sequence of an input number
 */
function toBits(n, bitCount) {
	var x = n;
	var bs = [];
	for (var b = 0; b < bitCount; b++) {
		x = n >> b;		
		bs.push(x & 0x01);
	}
	return bs.reverse();
}

/**
 * nicely print a binary number. omit trailing 0 after the dot.
 */
function toBinaryStr(bits) {	
	var suffix = bits.slice(1).join('').replace(/0+$/, '');
	suffix = suffix.length == 0? '0': suffix;
	return bits[0] + '.' + suffix;
}

function toMathString(n) {
	var buffer = new ArrayBuffer(4);
	new DataView(buffer).setFloat32(0, n);
	var bytes = new Uint8Array(buffer);

	// 0 - positive, 1 - negative
  var signBit = (bytes[0] >> 7);
	var sign = signBit > 0 ? '-': '';
	var exp = (bytes[0] << 1) | (bytes[1] >> 7);
	// expected: 126 , in binary 01111110
	// for float32, minus 127 from raw bits to get signed value
	var expVal = exp - 127;
	// expected: -1
	var expSign = expVal > 0? '': '-';


	// the most significant bit is 1 and is ommited
	// So we put it back here
	var sig = (((bytes[1] & 0x7F) | 0x80) << 16) | (bytes[2] << 8) | bytes[3];

	// expected: 8388608 , which is 10...0 (23 zeros)
	var mathRep = toBinaryStr(toBits(sig, 24)) + 'E' 
			+ expSign 
			+ toBits(Math.abs(expVal), 8).join('').replace(/^0+/,'');
	return [mathRep, signBit, 
          toBits(exp, 8).join(''), 
          toBits(sig, 23).join('')];
}
            
          
!
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