30:T3d05,function binaryInput(opts) { var type = opts.type; var byteSeparation = opts.byteSeparation === undefined ? '5px' : opts.byteSeparation; var format = opts.format === undefined ? x => x : opts.format; var displayParts = opts.displayParts === undefined ? false : opts.displayParts; var fractionalSignificand = opts.fractionalSignificand === undefined ? false : !!opts.fractionalSignificand; var outputAsBytes = opts.outputAsBytes === undefined ? false : !!opts.outputAsBytes; var BigInt64Array = window.BigInt64Array; var BigUint64Array = window.BigUint64Array; var BigInt = window.BigInt; var Ctor; var length; var signLength = 0; var exponentLength = 0; var offset = 0; switch (type) { case 'float16': Ctor = Float32Array; length = 16; signLength = 1; exponentLength = 5; offset = 15; break; case 'float': case 'float32': Ctor = Float32Array; length = 32; signLength = 1; exponentLength = 8; offset = 127; break; case 'double': case 'float64': Ctor = Float64Array; length = 64; signLength = 1; exponentLength = 11; offset = 1023; break; case 'uint8': Ctor = Uint8Array; length = 8; break; case 'int8': Ctor = Int8Array; length = 8; signLength = 1; break; case 'uint16': Ctor = Uint16Array; length = 16; break; case 'int16': Ctor = Int16Array; length = 16; signLength = 1; break; case 'uint32': Ctor = Uint32Array; length = 32; break; case 'int32': Ctor = Int32Array; length = 32; signLength = 1; break; case 'uint64': Ctor = BigUint64Array; length = 64; signLength = 0; break; case 'int64': Ctor = BigInt64Array; length = 64; signLength = 1; break; default: throw new Error( `Unexpected type "${type}". Options are 'float' ('float32'), 'double' ('float64'), 'uint8', 'int8', 'uint16', 'int16', 'uint32', and 'int32'` ); } if ( !window.BigInt && exponentLength && fractionalSignificand && length > 32 ) { throw new Error( 'BigInt support must be present to display fractions for single or double precision floats' ); } // If we don't need anything special, fake it with a pass-through var BigInt = window.BigInt || function(x) { return x; }; var valueAsArray; var bytes; if (type === 'float16') { // Typed array interpretation-style casting doesn't work for float16 since // JavaScript doesn't support it. Instead we'll have to do this manually. bytes = new Uint8Array(2); if (opts.literalValue !== undefined) { bytes[0] = opts.literalValue & 0x00ff; bytes[1] = (opts.literalValue & 0xff00) >> 8; } else if (opts.value !== undefined) { var floatValue = new Float32Array([opts.value]); var floatBytes = new Uint8Array(floatValue.buffer); var signBit = (floatBytes[3] & 0b10000000) >> 7; var exponent32 = ((floatBytes[3] & 0b01111111) << 1) | ((floatBytes[2] & 0b10000000) >> 7); var exponent16 = exponent32 - 127 + 15; var significand = ((floatBytes[2] & 0b01111111) << 3) | ((floatBytes[1] & 0b11100000) >> 5); bytes[1] = (signBit << 7) | (exponent16 << 2) | ((significand & 0b1100000000) >> 8); bytes[0] = significand & 0b11111111; } } else { if (opts.literalValue === undefined) { var value = opts.value === undefined ? 0 : opts.value; valueAsArray = new Ctor([ Ctor === BigInt64Array || Ctor === BigUint64Array ? BigInt(value) : value ]); bytes = new Uint8Array(valueAsArray.buffer); } else { valueAsArray = new Ctor([ Ctor === BigInt64Array || Ctor === BigUint64Array ? BigInt(0) : 0 ]); bytes = new Uint8Array(valueAsArray.buffer); for (var i = 0; i < length >> 3; i++) { bytes[i] = (opts.literalValue & (0xff << (i * 8))) >> (i * 8); } } } const container = document.createElement('div'); if (opts.title) { const title = document.createElement('div'); title.style.font = '700 0.9rem sans-serif'; title.textContent = opts.title; title.style.marginBottom = '0.2rem'; container.appendChild(title); } const editor = document.createElement('div'); container.appendChild(editor); editor.style.fontFamily = 'monospace'; editor.style.fontSize = '0.9rem'; // Debatable. It's easy to accidentally select when trying to toggle bits. editor.style.userSelect = 'none'; let debugEl; if (true) { debugEl = document.createElement('div'); editor.appendChild(debugEl); } let output, partsDisplay; const outputContainer = document.createElement('div'); container.append(outputContainer); if (format) { output = document.createElement('output'); output.style.font = '14px Menlo, Consolas, monospace'; outputContainer.appendChild(output); } if (displayParts) { partsDisplay = document.createElement('span'); outputContainer.appendChild(partsDisplay); } if (opts.description) { const description = document.createElement('div'); description.style.fontSize = '0.85rem'; description.style.fontStyle = 'italic'; description.textContent = opts.description; container.appendChild(description); } function getBit(bit) { // bit >> 3 divides by eight and tells which byte this belongs to // bit & 0x7 gives the rest of the location. So basically we shift // the value right to isolate the correct byte, then and it with the // particular bit we want. return bytes[bit >> 3] & (0x1 << (bit & 0x7)) ? 1 : 0; } function getSignBit() { if (!signLength) return 0; return bytes[bytes.length - 1] & 0x80; } function getMantissaBits() { if (!exponentLength) return valueAsArray[0] & ~(1 << (length - 1)); switch (length) { case 16: return bytes[0] | ((bytes[1] & 0x3) << 8); case 32: return ((bytes[2] & 0x7f) << 16) | (bytes[1] << 8) | bytes[0]; case 64: return ( ((BigInt(bytes[6]) & BigInt(0xf)) << BigInt(48)) + (BigInt(bytes[5]) << BigInt(40)) + (BigInt(bytes[4]) << BigInt(32)) + BigInt( (bytes[3] << 24) + (bytes[2] << 16) + (bytes[1] << 8) + bytes[0] ) ); } } function getExponentBits() { if (!exponentLength) return 0; switch (length) { case 64: return ((bytes[7] & 0x7f) << 4) | (bytes[6] >> 4); case 32: return ((bytes[3] & 0x7f) << 1) | (bytes[2] >> 7); case 16: return (bytes[1] & 0x7c) >> 2; } } function getSign() { return getSignBit() ? -1 : 1; } function isDenormal() { if (!exponentLength) return false; switch (length) { case 64: return ( !(bytes[bytes.length - 1] & 0x7f) && !(bytes[bytes.length - 2] & 0xf0) ); case 32: return ( !(bytes[bytes.length - 1] & 0x7f) && !(bytes[bytes.length - 2] & 0x80) ); case 16: return !(bytes[1] & 0x7c); } } function getMantissa() { if (type === 'float16') { return ( (bytes[0] | ((bytes[1] & 0x3) << 8)) / 1024 + (isDenormal() ? 1 : 0) ); } var bytesCopy = new Uint8Array(bytes.slice()); var normalOffset = 0; var typedMantissa = new Ctor(bytesCopy.buffer); if (exponentLength) { bytesCopy[bytesCopy.length - 1] = 0x3f; bytesCopy[bytesCopy.length - 2] = bytesCopy[bytesCopy.length - 2] | (length === 32 ? 0x80 : 0xf0); } else if (signLength) { if (!exponentLength && getSign() === -1) { for (var i = 0; i < bytesCopy.length; i++) { bytesCopy[i] = ~bytesCopy[i]; } normalOffset = 1; } // Unset the sign bit bytesCopy[bytesCopy.length - 1] = bytesCopy[bytesCopy.length - 1] & 0x7f; } if (normalOffset) { typedMantissa[0] += normalOffset; } return typedMantissa[0]; } function getExponentBits() { if (!exponentLength) return 0; switch (length) { case 64: return ((bytes[7] & 0x7f) << 4) | (bytes[6] >> 4); case 32: return ((bytes[3] & 0x7f) << 1) | (bytes[2] >> 7); case 16: return (bytes[1] & 0x7c) >> 2; } } function getExponent() { if (!exponentLength) return 0; switch (length) { case 64: return Math.max(-1022, getExponentBits() - 0x3ff); case 32: return Math.max(-126, getExponentBits() - 0x7f); case 16: return Math.max(-14, getExponentBits() - 0xf); } } function getValue() { if (type === 'float16') { // Javascript doesn't support half-float, so we'll tease it apart and insert // the corresponding parts into a float32 instead. var floatBytes = new Uint8Array(4); // Isolate the sign bit: var signBit = (bytes[1] & 0b10000000) >> 7; // Isolate the mantissa var mantissa = ((bytes[1] & 0b00000011) << 8) | bytes[0]; // Isolate the exponent: var exponent16 = (bytes[1] & 0b01111100) >> 2; var exponent32 = exponent16 - 15 + 127; if (exponent16 === 0) { // Subnormal. This one is tricky so we'll just do it mathematically instead of bitwise return (signBit > 0 ? -1 : 1) * Math.pow(2, -14) * (mantissa / 1024); } else if (exponent16 === 31) { // Transfer this special case into the 32-bit exponent exponent32 = 255; } // Combine the sign and exponent into the first byte floatBytes[3] = (signBit << 7) | ((exponent32 & 0b11111110) >> 1); floatBytes[2] = ((exponent32 & 0b1) << 7) | ((mantissa & 0b1111111000) >> 3); floatBytes[1] = (mantissa & 0b00000111) << 5; floatBytes[0] = 0; return new Float32Array(floatBytes.buffer)[0]; } return valueAsArray[0]; } const bitSpans = []; function writeBits() { for (var i = 0; i < length; i++) { bitSpans[i].textContent = getBit(i); } if (output) output.textContent = format(getValue()); if (partsDisplay) { let el = document.createElement('span'); el.appendChild(tex`\; = \;`); if (signLength) { let signContainer = document.createElement('span'); signContainer.appendChild(tex`${getSign()}`); signContainer.style.backgroundColor = 'rgba(0, 0, 210, 0.25)'; signContainer.style.padding = '0 0.15em'; el.append(signContainer); el.appendChild(tex`\; \times \;`); } if (exponentLength) { let exponentContainer = document.createElement('span'); exponentContainer.appendChild(tex`2^{${getExponent()}}`); exponentContainer.style.backgroundColor = 'rgba(0, 210, 0, 0.25)'; exponentContainer.style.padding = '0 0.15em'; el.append(exponentContainer); el.appendChild(tex`\; \times \;`); } var mantissaContainer = document.createElement('span'); if (exponentLength && fractionalSignificand) { mantissaContainer.appendChild( tex`\left(${ isDenormal() ? 0 : 1 } + \frac{${getMantissaBits()}}{${BigInt(1) << BigInt(length - signLength - exponentLength)}}\right)` ); } else { var mantissaStr = getMantissa().toString(); if (isDenormal()) mantissaStr = mantissaStr.replace(/^1/, '0'); mantissaContainer.appendChild(tex`${mantissaStr}`); } mantissaContainer.style.backgroundColor = 'rgba(210, 0, 0, 0.25)'; mantissaContainer.style.padding = '0 0.15em'; el.appendChild(mantissaContainer); if (partsDisplay.firstChild) partsDisplay.firstChild.remove(); partsDisplay.appendChild(el); } container.value = outputAsBytes ? bytes : getValue(); } var curBit = 0; function toggleBit(bit, event) { curBit = bit; bitSpans[curBit].focus(); // Similar to above, we isolate the bit we're interested in, then // construct the bit we want to toggle. Typed array casting via buffer // views magically handles interpretation for us. bytes[bit >> 3] = bytes[bit >> 3] ^ (0x1 << (bit & 0x7)); writeBits(); container.dispatchEvent(new CustomEvent('input')); } function setBit(bit, value) { curBit = bit; if (value) { bytes[bit >> 3] = bytes[bit >> 3] | (0x1 << (bit & 0x7)); } else { bytes[bit >> 3] = bytes[bit >> 3] & ~(0x1 << (bit & 0x7)); } writeBits(); container.dispatchEvent(new CustomEvent('input')); } function nextBit() { curBit++; bitSpans[curBit].focus(); } function prevBit() { if (curBit === length - 1) return false; curBit++; bitSpans[curBit].focus(); return true; } function nextBit() { if (curBit === 0) return false; curBit--; bitSpans[curBit].focus(); return true; } function focusBit(i) { curBit = i; } function handleKeypress(event) { switch (event.keyCode) { case 8: setBit(curBit, 0); prevBit(); event.preventDefault(); break; case 9: if (event.shiftKey) { if (prevBit()) event.preventDefault(); } else { if (nextBit()) event.preventDefault(); } break; case 37: if (prevBit()) event.preventDefault(); break; case 39: if (nextBit()) event.preventDefault(); break; case 48: setBit(curBit, 0); nextBit(); event.preventDefault(); break; case 49: setBit(curBit, 1); nextBit(); event.preventDefault(); break; } } let bit = length - 1; for (let byte = bytes.length - 1; byte >= 0; byte--) { const byteSpan = document.createElement('span'); byteSpan.style.display = 'inline-block'; byteSpan.style.marginRight = byteSeparation; byteSpan.style.marginBottom = '2px'; for (let i = 0; i < 8; i++) { const bitSpan = document.createElement('button'); byteSpan.append(bitSpan); bitSpans.unshift(bitSpan); bitSpan.style.width = '15px'; bitSpan.style.height = '20px'; bitSpan.style.display = 'inline'; bitSpan.style.border = '1px solid black'; bitSpan.style.verticalAlign = 'middle'; bitSpan.style.padding = '0'; bitSpan.style.textAlign = 'center'; bitSpan.style.marginRight = '-1px'; bitSpan.style.lineHeight = '20px'; bitSpan.style.cursor = 'pointer'; bitSpan.style.fontFamily = 'monospace'; bitSpan.style.borderRadius = 0; bitSpan.style.fontSize = '0.9rem'; bitSpan.style.backgroundColor = 'transparent'; if (signLength > 0 || exponentLength > 0) { if (bit < length - signLength - exponentLength) { bitSpan.style.backgroundColor = 'rgba(210, 0, 0, 0.25)'; } else if (bit < length - signLength) { bitSpan.style.backgroundColor = 'rgba(0, 210, 0, 0.25)'; } else { bitSpan.style.backgroundColor = 'rgba(0, 0, 210, 0.25)'; } } bitSpan.addEventListener('focus', focusBit.bind(null, bit)); bitSpan.addEventListener('click', toggleBit.bind(null, bit)); bit--; } editor.append(byteSpan); } editor.addEventListener('keydown', handleKeypress); writeBits(); container.value = outputAsBytes ? bytes : getValue(); return container; }31:T44e,md`--- ## Configuration - \`value\`: initial value. (default: \`0\`) - \`title\`: input title. (default: \`''\`) - \`description\`: input description. (default: \`''\`) - \`format\`: custom callback for formatting output. Receives current value. - \`byteSeparation\`: adds a bit of separation between bytes. (default: \`5px\`) - \`displayParts\`: display the sign, exponent, and mantissa separately (default: false) - \`fractionalSignificand\`: If \`displayParts\` is \`true\`, displays significand as a fraction rather than with a [radix point](https://en.wikipedia.org/wiki/Radix_point). - \`outputAsBytes\`: If \`true\`, outputs the value as a \`Uint8Array\` of bytes rather than a typed value - \`type\`: data type. Valid \`type\`s are: - \`uint8\` - \`int8\` - \`uint16\` - \`int16\` - \`uint32\` - \`int32\` - \`uint64\` - \`int64\` - \`float16\` - \`float32\` (a.k.a. \`float\`) - \`float64\` (a.k.a. \`double\`) Arrow keys, spacebar, tab, delete, and 0 and 1 keys work for quick editing. --- ## Examples Types without an exponent or sign bit show up without color: `32:[] 2e:{"title":"Binary Input","cells":[{"id":0,"value":"md`# Binary Input\n\nInspired by [@jrus](https://observablehq.com/@jrus) and [Float Toy](https://evanw.github.io/float-toy/).\n\n---`","pinned":false,"hidden":false,"mode":"ojs"},{"id":492,"value":"binaryInput({\n type: 'float64',\n value: Math.PI,\n displayParts: true\n})","pinned":true,"hidden":false,"mode":"ojs"},{"id":258,"value":"md`---\n## Implementation`","pinned":false,"hidden":false,"mode":"ojs"},{"id":21,"value":"$30","pinned":false,"hidden":false,"mode":"ojs"},{"id":253,"value":"$31","pinned":false,"hidden":false,"mode":"ojs"},{"id":249,"value":"viewof x = binaryInput({\n type: 'uint32',\n value: 0xff00ff00\n})","pinned":true,"hidden":false,"mode":"ojs"},{"id":293,"value":"x","pinned":true,"hidden":false,"mode":"ojs"},{"id":276,"value":"md`---\n\nFor other types, bits are colored by sign, exponent, and significand (equivalently, *mantissa*) ranges, respectively. You may optionally display the parts separately with \\`displayParts\\`.`","pinned":false,"hidden":false,"mode":"ojs"},{"id":243,"value":"binaryInput({\n type: 'float32',\n value: Math.PI,\n displayParts: true\n})","pinned":true,"hidden":false,"mode":"ojs"},{"id":1025,"value":"md`---\n\nTo help interpretation, numbers with an exponent may be displayed with a fractional significand.`","pinned":false,"hidden":false,"mode":"ojs"},{"id":1028,"value":"binaryInput({\n type: 'float32',\n value: 65504,\n displayParts: true,\n fractionalSignificand: true\n})","pinned":true,"hidden":false,"mode":"ojs"},{"id":1107,"value":"md`---\n\nJavaScript does not support half-precision (16-bit) floating-point numbers. You may specify \\`float16\\` type and provide a value, but if you require specifying the exact bits, you'll need to provide the \\`literalValue\\` instead.`","pinned":false,"hidden":false,"mode":"ojs"},{"id":1112,"value":"binaryInput({\n type: 'float16',\n literalValue: 0b0100001001001000,\n displayParts: true,\n fractionalSignificand: true\n})","pinned":true,"hidden":false,"mode":"ojs"},{"id":464,"value":"md`---\n\nSigned integer types have a sign bit and a significand but not an exponent.`","pinned":false,"hidden":false,"mode":"ojs"},{"id":289,"value":"binaryInput({\n type: 'int32',\n value: -256\n})","pinned":true,"hidden":false,"mode":"ojs"},{"id":261,"value":"md`---\n\nIn the style of [@jashkenas/inputs](https://observablehq.com/@jashkenas/inputs), the input supports \\`title\\` and \\`description\\` options as well.`","pinned":false,"hidden":false,"mode":"ojs"},{"id":107,"value":"binaryInput({\n type: 'double',\n value: Math.PI,\n title: 'Float64 binary input',\n description: 'Click to toggle the bits!'\n})","pinned":true,"hidden":false,"mode":"ojs"},{"id":432,"value":"md`---\n\nYou may apply custom formatting. Providing \\`format: false\\` hides the output.`","pinned":false,"hidden":false,"mode":"ojs"},{"id":428,"value":"binaryInput({\n type: 'uint32',\n value: 0xff00ff00,\n format: value => `0x${value.toString(16).padStart(8, '0')}`\n})","pinned":true,"hidden":false,"mode":"ojs"}],"files":"$W32","stdlib":"1","titling":"auto"}