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// Copyright (c) 2008, Fair Oaks Labs, Inc.// All rights reserved.//// Redistribution and use in source and binary forms, with or without// modification, are permitted provided that the following conditions are met:////  * Redistributions of source code must retain the above copyright notice,//    this list of conditions and the following disclaimer.////  * Redistributions in binary form must reproduce the above copyright notice,//    this list of conditions and the following disclaimer in the documentation//    and/or other materials provided with the distribution.////  * Neither the name of Fair Oaks Labs, Inc. nor the names of its contributors//    may be used to endorse or promote products derived from this software//    without specific prior written permission.//// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"// AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE// IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE// ARE DISCLAIMED.  IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE// LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR// CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF// SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS// INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN// CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)// ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE// POSSIBILITY OF SUCH DAMAGE.////// Modifications to writeIEEE754 to support negative zeroes made by Brian White
type NumericalSequence = { [index: number]: number };
export function readIEEE754(  buffer: NumericalSequence,  offset: number,  endian: "big" | "little",  mLen: number,  nBytes: number,): number {  let e: number;  let m: number;  const bBE = endian === "big";  const eLen = nBytes * 8 - mLen - 1;  const eMax = (1 << eLen) - 1;  const eBias = eMax >> 1;  let nBits = -7;  let i = bBE ? 0 : nBytes - 1;  const d = bBE ? 1 : -1;  let s = buffer[offset + i];
  i += d;
  e = s & ((1 << -nBits) - 1);  s >>= -nBits;  nBits += eLen;  for (; nBits > 0; e = e * 256 + buffer[offset + i], i += d, nBits -= 8);
  m = e & ((1 << -nBits) - 1);  e >>= -nBits;  nBits += mLen;  for (; nBits > 0; m = m * 256 + buffer[offset + i], i += d, nBits -= 8);
  if (e === 0) {    e = 1 - eBias;  } else if (e === eMax) {    return m ? NaN : (s ? -1 : 1) * Infinity;  } else {    m = m + Math.pow(2, mLen);    e = e - eBias;  }  return (s ? -1 : 1) * m * Math.pow(2, e - mLen);}
export function writeIEEE754(  buffer: NumericalSequence,  value: number,  offset: number,  endian: "big" | "little",  mLen: number,  nBytes: number,): void {  let e: number;  let m: number;  let c: number;  const bBE = endian === "big";  let eLen = nBytes * 8 - mLen - 1;  const eMax = (1 << eLen) - 1;  const eBias = eMax >> 1;  const rt = mLen === 23 ? Math.pow(2, -24) - Math.pow(2, -77) : 0;  let i = bBE ? nBytes - 1 : 0;  const d = bBE ? -1 : 1;  const s = value < 0 || (value === 0 && 1 / value < 0) ? 1 : 0;
  value = Math.abs(value);
  if (isNaN(value) || value === Infinity) {    m = isNaN(value) ? 1 : 0;    e = eMax;  } else {    e = Math.floor(Math.log(value) / Math.LN2);    if (value * (c = Math.pow(2, -e)) < 1) {      e--;      c *= 2;    }    if (e + eBias >= 1) {      value += rt / c;    } else {      value += rt * Math.pow(2, 1 - eBias);    }    if (value * c >= 2) {      e++;      c /= 2;    }
    if (e + eBias >= eMax) {      m = 0;      e = eMax;    } else if (e + eBias >= 1) {      m = (value * c - 1) * Math.pow(2, mLen);      e = e + eBias;    } else {      m = value * Math.pow(2, eBias - 1) * Math.pow(2, mLen);      e = 0;    }  }
  if (isNaN(value)) m = 0;
  while (mLen >= 8) {    buffer[offset + i] = m & 0xff;    i += d;    m /= 256;    mLen -= 8;  }
  e = (e << mLen) | m;
  if (isNaN(value)) e += 8;
  eLen += mLen;
  while (eLen > 0) {    buffer[offset + i] = e & 0xff;    i += d;    e /= 256;    eLen -= 8;  }
  buffer[offset + i - d] |= s * 128;}