jspredict-dc/dist/jspredict-dc.esm.mjs.map

Satellite propagation and visibility utilities built on satellite.js.

{"version":3,"file":"jspredict-dc.esm.mjs","sources":["../src/runtime.js","../node_modules/satellite.js/dist/satellite.es.js","../src/utils.js","../src/constants.js","../src/core.js","../src/index.js?commonjs-entry","../src/index.js"],"sourcesContent":["// 这里保存的是库级别的可变运行时状态，只用于控制迭代次数和调试日志。\r\nmodule.exports = {\r\n  printIntervalInfo: false,\r\n  maxIterations: 99999,\r\n};\r\n","var pi = Math.PI;\nvar twoPi = pi * 2;\nvar deg2rad = pi / 180.0;\nvar rad2deg = 180 / pi;\nvar minutesPerDay = 1440.0;\nvar mu = 398600.8; // in km3 / s2\nvar earthRadius = 6378.135; // in km\nvar xke = 60.0 / Math.sqrt(earthRadius * earthRadius * earthRadius / mu);\nvar vkmpersec = earthRadius * xke / 60.0;\nvar tumin = 1.0 / xke;\nvar j2 = 0.001082616;\nvar j3 = -0.00000253881;\nvar j4 = -0.00000165597;\nvar j3oj2 = j3 / j2;\nvar x2o3 = 2.0 / 3.0;\nvar xpdotp = 1440.0 / (2.0 * pi); // 229.1831180523293;\n\nvar constants = /*#__PURE__*/Object.freeze({\n    __proto__: null,\n    deg2rad: deg2rad,\n    earthRadius: earthRadius,\n    j2: j2,\n    j3: j3,\n    j3oj2: j3oj2,\n    j4: j4,\n    minutesPerDay: minutesPerDay,\n    mu: mu,\n    pi: pi,\n    rad2deg: rad2deg,\n    tumin: tumin,\n    twoPi: twoPi,\n    vkmpersec: vkmpersec,\n    x2o3: x2o3,\n    xke: xke,\n    xpdotp: xpdotp\n});\n\n/* -----------------------------------------------------------------------------\n *\n *                           procedure days2mdhms\n *\n *  this procedure converts the day of the year, days, to the equivalent month\n *    day, hour, minute and second.\n *\n *  algorithm     : set up array for the number of days per month\n *                  find leap year - use 1900 because 2000 is a leap year\n *                  loop through a temp value while the value is < the days\n *                  perform int conversions to the correct day and month\n *                  convert remainder into h m s using type conversions\n *\n *  author        : david vallado                  719-573-2600    1 mar 2001\n *\n *  inputs          description                    range / units\n *    year        - year                           1900 .. 2100\n *    days        - julian day of the year         0.0  .. 366.0\n *\n *  outputs       :\n *    mon         - month                          1 .. 12\n *    day         - day                            1 .. 28,29,30,31\n *    hr          - hour                           0 .. 23\n *    min         - minute                         0 .. 59\n *    sec         - second                         0.0 .. 59.999\n *\n *  locals        :\n *    dayofyr     - day of year\n *    temp        - temporary extended values\n *    inttemp     - temporary int value\n *    i           - index\n *    lmonth[12]  - int array containing the number of days per month\n *\n *  coupling      :\n *    none.\n * --------------------------------------------------------------------------- */\nfunction days2mdhms(year, days) {\n  var lmonth = [31, year % 4 === 0 ? 29 : 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31];\n  var dayofyr = Math.floor(days);\n  //  ----------------- find month and day of month ----------------\n  var i = 1;\n  var inttemp = 0;\n  // i starts from 1 so no null check is needed\n  while (dayofyr > inttemp + lmonth[i - 1] && i < 12) {\n    inttemp += lmonth[i - 1];\n    i += 1;\n  }\n  var mon = i;\n  var day = dayofyr - inttemp;\n  //  ----------------- find hours minutes and seconds -------------\n  var temp = (days - dayofyr) * 24.0;\n  var hr = Math.floor(temp);\n  temp = (temp - hr) * 60.0;\n  var minute = Math.floor(temp);\n  var sec = (temp - minute) * 60.0;\n  return {\n    mon: mon,\n    day: day,\n    hr: hr,\n    minute: minute,\n    sec: sec\n  };\n}\n/* -----------------------------------------------------------------------------\n *\n *                           procedure jday\n *\n *  this procedure finds the julian date given the year, month, day, and time.\n *    the julian date is defined by each elapsed day since noon, jan 1, 4713 bc.\n *\n *  algorithm     : calculate the answer in one step for efficiency\n *\n *  author        : david vallado                  719-573-2600    1 mar 2001\n *\n *  inputs          description                    range / units\n *    year        - year                           1900 .. 2100\n *    mon         - month                          1 .. 12\n *    day         - day                            1 .. 28,29,30,31\n *    hr          - universal time hour            0 .. 23\n *    min         - universal time min             0 .. 59\n *    sec         - universal time sec             0.0 .. 59.999\n *\n *  outputs       :\n *    jd          - julian date                    days from 4713 bc\n *\n *  locals        :\n *    none.\n *\n *  coupling      :\n *    none.\n *\n *  references    :\n *    vallado       2007, 189, alg 14, ex 3-14\n *\n * --------------------------------------------------------------------------- */\nfunction jdayInternal(year, mon, day, hr, minute, sec) {\n  var msec = arguments.length > 6 && arguments[6] !== undefined ? arguments[6] : 0;\n  return 367.0 * year - Math.floor(7 * (year + Math.floor((mon + 9) / 12.0)) * 0.25) + Math.floor(275 * mon / 9.0) + day + 1721013.5 + ((msec / 60000 + sec / 60.0 + minute) / 60.0 + hr) / 24.0 // ut in days\n  // # - 0.5*sgn(100.0*year + mon - 190002.5) + 0.5;\n  ;\n}\nfunction jday(yearOrDate, mon, day, hr, minute, sec) {\n  var msec = arguments.length > 6 && arguments[6] !== undefined ? arguments[6] : 0;\n  if (yearOrDate instanceof Date) {\n    var date = yearOrDate;\n    return jdayInternal(date.getUTCFullYear(), date.getUTCMonth() + 1,\n    // Note, this function requires months in range 1-12.\n    date.getUTCDate(), date.getUTCHours(), date.getUTCMinutes(), date.getUTCSeconds(), date.getUTCMilliseconds());\n  }\n  return jdayInternal(yearOrDate, mon, day, hr, minute, sec, msec);\n}\nfunction invjday(jd, asArray) {\n  // --------------- find year and days of the year -\n  var temp = jd - 2415019.5;\n  var tu = temp / 365.25;\n  var year = 1900 + Math.floor(tu);\n  var leapyrs = Math.floor((year - 1901) * 0.25);\n  // optional nudge by 8.64x10-7 sec to get even outputs\n  var days = temp - ((year - 1900) * 365.0 + leapyrs) + 0.00000000001;\n  // ------------ check for case of beginning of a year -----------\n  if (days < 1.0) {\n    year -= 1;\n    leapyrs = Math.floor((year - 1901) * 0.25);\n    days = temp - ((year - 1900) * 365.0 + leapyrs);\n  }\n  // ----------------- find remaing data  -------------------------\n  var mdhms = days2mdhms(year, days);\n  var mon = mdhms.mon,\n    day = mdhms.day,\n    hr = mdhms.hr,\n    minute = mdhms.minute;\n  var sec = mdhms.sec - 0.00000086400;\n  if (asArray) {\n    return [year, mon, day, hr, minute, Math.floor(sec)];\n  }\n  return new Date(Date.UTC(year, mon - 1, day, hr, minute, Math.floor(sec)));\n}\n\n/* -----------------------------------------------------------------------------\n *\n *                           procedure dpper\n *\n *  this procedure provides deep space long period periodic contributions\n *    to the mean elements.  by design, these periodics are zero at epoch.\n *    this used to be dscom which included initialization, but it's really a\n *    recurring function.\n *\n *  author        : david vallado                  719-573-2600   28 jun 2005\n *\n *  inputs        :\n *    e3          -\n *    ee2         -\n *    peo         -\n *    pgho        -\n *    pho         -\n *    pinco       -\n *    plo         -\n *    se2 , se3 , sgh2, sgh3, sgh4, sh2, sh3, si2, si3, sl2, sl3, sl4 -\n *    t           -\n *    xh2, xh3, xi2, xi3, xl2, xl3, xl4 -\n *    zmol        -\n *    zmos        -\n *    ep          - eccentricity                           0.0 - 1.0\n *    inclo       - inclination - needed for lyddane modification\n *    nodep       - right ascension of ascending node\n *    argpp       - argument of perigee\n *    mp          - mean anomaly\n *\n *  outputs       :\n *    ep          - eccentricity                           0.0 - 1.0\n *    inclp       - inclination\n *    nodep        - right ascension of ascending node\n *    argpp       - argument of perigee\n *    mp          - mean anomaly\n *\n *  locals        :\n *    alfdp       -\n *    betdp       -\n *    cosip  , sinip  , cosop  , sinop  ,\n *    dalf        -\n *    dbet        -\n *    dls         -\n *    f2, f3      -\n *    pe          -\n *    pgh         -\n *    ph          -\n *    pinc        -\n *    pl          -\n *    sel   , ses   , sghl  , sghs  , shl   , shs   , sil   , sinzf , sis   ,\n *    sll   , sls\n *    xls         -\n *    xnoh        -\n *    zf          -\n *    zm          -\n *\n *  coupling      :\n *    none.\n *\n *  references    :\n *    hoots, roehrich, norad spacetrack report #3 1980\n *    hoots, norad spacetrack report #6 1986\n *    hoots, schumacher and glover 2004\n *    vallado, crawford, hujsak, kelso  2006\n ----------------------------------------------------------------------------*/\nfunction dpper(satrec, options) {\n  var e3 = satrec.e3,\n    ee2 = satrec.ee2,\n    peo = satrec.peo,\n    pgho = satrec.pgho,\n    pho = satrec.pho,\n    pinco = satrec.pinco,\n    plo = satrec.plo,\n    se2 = satrec.se2,\n    se3 = satrec.se3,\n    sgh2 = satrec.sgh2,\n    sgh3 = satrec.sgh3,\n    sgh4 = satrec.sgh4,\n    sh2 = satrec.sh2,\n    sh3 = satrec.sh3,\n    si2 = satrec.si2,\n    si3 = satrec.si3,\n    sl2 = satrec.sl2,\n    sl3 = satrec.sl3,\n    sl4 = satrec.sl4,\n    t = satrec.t,\n    xgh2 = satrec.xgh2,\n    xgh3 = satrec.xgh3,\n    xgh4 = satrec.xgh4,\n    xh2 = satrec.xh2,\n    xh3 = satrec.xh3,\n    xi2 = satrec.xi2,\n    xi3 = satrec.xi3,\n    xl2 = satrec.xl2,\n    xl3 = satrec.xl3,\n    xl4 = satrec.xl4,\n    zmol = satrec.zmol,\n    zmos = satrec.zmos;\n  var init = options.init,\n    opsmode = options.opsmode;\n  var ep = options.ep,\n    inclp = options.inclp,\n    nodep = options.nodep,\n    argpp = options.argpp,\n    mp = options.mp;\n  // Copy satellite attributes into local variables for convenience\n  // and symmetry in writing formulae.\n  var alfdp;\n  var betdp;\n  var cosip;\n  var sinip;\n  var cosop;\n  var sinop;\n  var dalf;\n  var dbet;\n  var dls;\n  var f2;\n  var f3;\n  var pe;\n  var pgh;\n  var ph;\n  var pinc;\n  var pl;\n  var sinzf;\n  var xls;\n  var xnoh;\n  var zf;\n  var zm;\n  //  ---------------------- constants -----------------------------\n  var zns = 1.19459e-5;\n  var zes = 0.01675;\n  var znl = 1.5835218e-4;\n  var zel = 0.05490;\n  //  --------------- calculate time varying periodics -----------\n  zm = zmos + zns * t;\n  // be sure that the initial call has time set to zero\n  if (init === 'y') {\n    zm = zmos;\n  }\n  zf = zm + 2.0 * zes * Math.sin(zm);\n  sinzf = Math.sin(zf);\n  f2 = 0.5 * sinzf * sinzf - 0.25;\n  f3 = -0.5 * sinzf * Math.cos(zf);\n  var ses = se2 * f2 + se3 * f3;\n  var sis = si2 * f2 + si3 * f3;\n  var sls = sl2 * f2 + sl3 * f3 + sl4 * sinzf;\n  var sghs = sgh2 * f2 + sgh3 * f3 + sgh4 * sinzf;\n  var shs = sh2 * f2 + sh3 * f3;\n  zm = zmol + znl * t;\n  if (init === 'y') {\n    zm = zmol;\n  }\n  zf = zm + 2.0 * zel * Math.sin(zm);\n  sinzf = Math.sin(zf);\n  f2 = 0.5 * sinzf * sinzf - 0.25;\n  f3 = -0.5 * sinzf * Math.cos(zf);\n  var sel = ee2 * f2 + e3 * f3;\n  var sil = xi2 * f2 + xi3 * f3;\n  var sll = xl2 * f2 + xl3 * f3 + xl4 * sinzf;\n  var sghl = xgh2 * f2 + xgh3 * f3 + xgh4 * sinzf;\n  var shll = xh2 * f2 + xh3 * f3;\n  pe = ses + sel;\n  pinc = sis + sil;\n  pl = sls + sll;\n  pgh = sghs + sghl;\n  ph = shs + shll;\n  if (init === 'n') {\n    pe -= peo;\n    pinc -= pinco;\n    pl -= plo;\n    pgh -= pgho;\n    ph -= pho;\n    inclp += pinc;\n    ep += pe;\n    sinip = Math.sin(inclp);\n    cosip = Math.cos(inclp);\n    /* ----------------- apply periodics directly ------------ */\n    // sgp4fix for lyddane choice\n    // strn3 used original inclination - this is technically feasible\n    // gsfc used perturbed inclination - also technically feasible\n    // probably best to readjust the 0.2 limit value and limit discontinuity\n    // 0.2 rad = 11.45916 deg\n    // use next line for original strn3 approach and original inclination\n    // if (inclo >= 0.2)\n    // use next line for gsfc version and perturbed inclination\n    if (inclp >= 0.2) {\n      ph /= sinip;\n      pgh -= cosip * ph;\n      argpp += pgh;\n      nodep += ph;\n      mp += pl;\n    } else {\n      //  ---- apply periodics with lyddane modification ----\n      sinop = Math.sin(nodep);\n      cosop = Math.cos(nodep);\n      alfdp = sinip * sinop;\n      betdp = sinip * cosop;\n      dalf = ph * cosop + pinc * cosip * sinop;\n      dbet = -ph * sinop + pinc * cosip * cosop;\n      alfdp += dalf;\n      betdp += dbet;\n      nodep %= twoPi;\n      //  sgp4fix for afspc written intrinsic functions\n      //  nodep used without a trigonometric function ahead\n      if (nodep < 0.0 && opsmode === 'a') {\n        nodep += twoPi;\n      }\n      xls = mp + argpp + cosip * nodep;\n      dls = pl + pgh - pinc * nodep * sinip;\n      xls += dls;\n      xnoh = nodep;\n      nodep = Math.atan2(alfdp, betdp);\n      //  sgp4fix for afspc written intrinsic functions\n      //  nodep used without a trigonometric function ahead\n      if (nodep < 0.0 && opsmode === 'a') {\n        nodep += twoPi;\n      }\n      if (Math.abs(xnoh - nodep) > pi) {\n        if (nodep < xnoh) {\n          nodep += twoPi;\n        } else {\n          nodep -= twoPi;\n        }\n      }\n      mp += pl;\n      argpp = xls - mp - cosip * nodep;\n    }\n  }\n  return {\n    ep: ep,\n    inclp: inclp,\n    nodep: nodep,\n    argpp: argpp,\n    mp: mp\n  };\n}\n\n/*-----------------------------------------------------------------------------\n *\n *                           procedure dscom\n *\n *  this procedure provides deep space common items used by both the secular\n *    and periodics subroutines.  input is provided as shown. this routine\n *    used to be called dpper, but the functions inside weren't well organized.\n *\n *  author        : david vallado                  719-573-2600   28 jun 2005\n *\n *  inputs        :\n *    epoch       -\n *    ep          - eccentricity\n *    argpp       - argument of perigee\n *    tc          -\n *    inclp       - inclination\n *    nodep       - right ascension of ascending node\n *    np          - mean motion\n *\n *  outputs       :\n *    sinim  , cosim  , sinomm , cosomm , snodm  , cnodm\n *    day         -\n *    e3          -\n *    ee2         -\n *    em          - eccentricity\n *    emsq        - eccentricity squared\n *    gam         -\n *    peo         -\n *    pgho        -\n *    pho         -\n *    pinco       -\n *    plo         -\n *    rtemsq      -\n *    se2, se3         -\n *    sgh2, sgh3, sgh4        -\n *    sh2, sh3, si2, si3, sl2, sl3, sl4         -\n *    s1, s2, s3, s4, s5, s6, s7          -\n *    ss1, ss2, ss3, ss4, ss5, ss6, ss7, sz1, sz2, sz3         -\n *    sz11, sz12, sz13, sz21, sz22, sz23, sz31, sz32, sz33        -\n *    xgh2, xgh3, xgh4, xh2, xh3, xi2, xi3, xl2, xl3, xl4         -\n *    nm          - mean motion\n *    z1, z2, z3, z11, z12, z13, z21, z22, z23, z31, z32, z33         -\n *    zmol        -\n *    zmos        -\n *\n *  locals        :\n *    a1, a2, a3, a4, a5, a6, a7, a8, a9, a10         -\n *    betasq      -\n *    cc          -\n *    ctem, stem        -\n *    x1, x2, x3, x4, x5, x6, x7, x8          -\n *    xnodce      -\n *    xnoi        -\n *    zcosg  , zsing  , zcosgl , zsingl , zcosh  , zsinh  , zcoshl , zsinhl ,\n *    zcosi  , zsini  , zcosil , zsinil ,\n *    zx          -\n *    zy          -\n *\n *  coupling      :\n *    none.\n *\n *  references    :\n *    hoots, roehrich, norad spacetrack report #3 1980\n *    hoots, norad spacetrack report #6 1986\n *    hoots, schumacher and glover 2004\n *    vallado, crawford, hujsak, kelso  2006\n ----------------------------------------------------------------------------*/\nfunction dscom(options) {\n  var epoch = options.epoch,\n    ep = options.ep,\n    argpp = options.argpp,\n    tc = options.tc,\n    inclp = options.inclp,\n    nodep = options.nodep,\n    np = options.np;\n  var a1;\n  var a2;\n  var a3;\n  var a4;\n  var a5;\n  var a6;\n  var a7;\n  var a8;\n  var a9;\n  var a10;\n  var cc;\n  var x1;\n  var x2;\n  var x3;\n  var x4;\n  var x5;\n  var x6;\n  var x7;\n  var x8;\n  var zcosg;\n  var zsing;\n  var zcosh;\n  var zsinh;\n  var zcosi;\n  var zsini;\n  var ss1;\n  var ss2;\n  var ss3;\n  var ss4;\n  var ss5;\n  var ss6;\n  var ss7;\n  var sz1;\n  var sz2;\n  var sz3;\n  var sz11;\n  var sz12;\n  var sz13;\n  var sz21;\n  var sz22;\n  var sz23;\n  var sz31;\n  var sz32;\n  var sz33;\n  var s1;\n  var s2;\n  var s3;\n  var s4;\n  var s5;\n  var s6;\n  var s7;\n  var z1;\n  var z2;\n  var z3;\n  var z11;\n  var z12;\n  var z13;\n  var z21;\n  var z22;\n  var z23;\n  var z31;\n  var z32;\n  var z33;\n  // -------------------------- constants -------------------------\n  var zes = 0.01675;\n  var zel = 0.05490;\n  var c1ss = 2.9864797e-6;\n  var c1l = 4.7968065e-7;\n  var zsinis = 0.39785416;\n  var zcosis = 0.91744867;\n  var zcosgs = 0.1945905;\n  var zsings = -0.98088458;\n  //  --------------------- local variables ------------------------\n  var nm = np;\n  var em = ep;\n  var snodm = Math.sin(nodep);\n  var cnodm = Math.cos(nodep);\n  var sinomm = Math.sin(argpp);\n  var cosomm = Math.cos(argpp);\n  var sinim = Math.sin(inclp);\n  var cosim = Math.cos(inclp);\n  var emsq = em * em;\n  var betasq = 1.0 - emsq;\n  var rtemsq = Math.sqrt(betasq);\n  //  ----------------- initialize lunar solar terms ---------------\n  var peo = 0.0;\n  var pinco = 0.0;\n  var plo = 0.0;\n  var pgho = 0.0;\n  var pho = 0.0;\n  var day = epoch + 18261.5 + tc / 1440.0;\n  var xnodce = (4.5236020 - 9.2422029e-4 * day) % twoPi;\n  var stem = Math.sin(xnodce);\n  var ctem = Math.cos(xnodce);\n  var zcosil = 0.91375164 - 0.03568096 * ctem;\n  var zsinil = Math.sqrt(1.0 - zcosil * zcosil);\n  var zsinhl = 0.089683511 * stem / zsinil;\n  var zcoshl = Math.sqrt(1.0 - zsinhl * zsinhl);\n  var gam = 5.8351514 + 0.0019443680 * day;\n  var zx = 0.39785416 * stem / zsinil;\n  var zy = zcoshl * ctem + 0.91744867 * zsinhl * stem;\n  zx = Math.atan2(zx, zy);\n  zx += gam - xnodce;\n  var zcosgl = Math.cos(zx);\n  var zsingl = Math.sin(zx);\n  //  ------------------------- do solar terms ---------------------\n  zcosg = zcosgs;\n  zsing = zsings;\n  zcosi = zcosis;\n  zsini = zsinis;\n  zcosh = cnodm;\n  zsinh = snodm;\n  cc = c1ss;\n  var xnoi = 1.0 / nm;\n  var lsflg = 0;\n  while (lsflg < 2) {\n    lsflg += 1;\n    a1 = zcosg * zcosh + zsing * zcosi * zsinh;\n    a3 = -zsing * zcosh + zcosg * zcosi * zsinh;\n    a7 = -zcosg * zsinh + zsing * zcosi * zcosh;\n    a8 = zsing * zsini;\n    a9 = zsing * zsinh + zcosg * zcosi * zcosh;\n    a10 = zcosg * zsini;\n    a2 = cosim * a7 + sinim * a8;\n    a4 = cosim * a9 + sinim * a10;\n    a5 = -sinim * a7 + cosim * a8;\n    a6 = -sinim * a9 + cosim * a10;\n    x1 = a1 * cosomm + a2 * sinomm;\n    x2 = a3 * cosomm + a4 * sinomm;\n    x3 = -a1 * sinomm + a2 * cosomm;\n    x4 = -a3 * sinomm + a4 * cosomm;\n    x5 = a5 * sinomm;\n    x6 = a6 * sinomm;\n    x7 = a5 * cosomm;\n    x8 = a6 * cosomm;\n    z31 = 12.0 * x1 * x1 - 3.0 * x3 * x3;\n    z32 = 24.0 * x1 * x2 - 6.0 * x3 * x4;\n    z33 = 12.0 * x2 * x2 - 3.0 * x4 * x4;\n    z1 = 3.0 * (a1 * a1 + a2 * a2) + z31 * emsq;\n    z2 = 6.0 * (a1 * a3 + a2 * a4) + z32 * emsq;\n    z3 = 3.0 * (a3 * a3 + a4 * a4) + z33 * emsq;\n    z11 = -6.0 * a1 * a5 + emsq * (-24.0 * x1 * x7 - 6.0 * x3 * x5);\n    z12 = -6.0 * (a1 * a6 + a3 * a5) + emsq * (-24.0 * (x2 * x7 + x1 * x8) + -6.0 * (x3 * x6 + x4 * x5));\n    z13 = -6.0 * a3 * a6 + emsq * (-24.0 * x2 * x8 - 6.0 * x4 * x6);\n    z21 = 6.0 * a2 * a5 + emsq * (24.0 * x1 * x5 - 6.0 * x3 * x7);\n    z22 = 6.0 * (a4 * a5 + a2 * a6) + emsq * (24.0 * (x2 * x5 + x1 * x6) - 6.0 * (x4 * x7 + x3 * x8));\n    z23 = 6.0 * a4 * a6 + emsq * (24.0 * x2 * x6 - 6.0 * x4 * x8);\n    z1 = z1 + z1 + betasq * z31;\n    z2 = z2 + z2 + betasq * z32;\n    z3 = z3 + z3 + betasq * z33;\n    s3 = cc * xnoi;\n    s2 = -0.5 * s3 / rtemsq;\n    s4 = s3 * rtemsq;\n    s1 = -15.0 * em * s4;\n    s5 = x1 * x3 + x2 * x4;\n    s6 = x2 * x3 + x1 * x4;\n    s7 = x2 * x4 - x1 * x3;\n    //  ----------------------- do lunar terms -------------------\n    if (lsflg === 1) {\n      ss1 = s1;\n      ss2 = s2;\n      ss3 = s3;\n      ss4 = s4;\n      ss5 = s5;\n      ss6 = s6;\n      ss7 = s7;\n      sz1 = z1;\n      sz2 = z2;\n      sz3 = z3;\n      sz11 = z11;\n      sz12 = z12;\n      sz13 = z13;\n      sz21 = z21;\n      sz22 = z22;\n      sz23 = z23;\n      sz31 = z31;\n      sz32 = z32;\n      sz33 = z33;\n      zcosg = zcosgl;\n      zsing = zsingl;\n      zcosi = zcosil;\n      zsini = zsinil;\n      zcosh = zcoshl * cnodm + zsinhl * snodm;\n      zsinh = snodm * zcoshl - cnodm * zsinhl;\n      cc = c1l;\n    }\n  }\n  var zmol = (4.7199672 + (0.22997150 * day - gam)) % twoPi;\n  var zmos = (6.2565837 + 0.017201977 * day) % twoPi;\n  //  ------------------------ do solar terms ----------------------\n  var se2 = 2.0 * ss1 * ss6;\n  var se3 = 2.0 * ss1 * ss7;\n  var si2 = 2.0 * ss2 * sz12;\n  var si3 = 2.0 * ss2 * (sz13 - sz11);\n  var sl2 = -2.0 * ss3 * sz2;\n  var sl3 = -2.0 * ss3 * (sz3 - sz1);\n  var sl4 = -2.0 * ss3 * (-21.0 - 9.0 * emsq) * zes;\n  var sgh2 = 2.0 * ss4 * sz32;\n  var sgh3 = 2.0 * ss4 * (sz33 - sz31);\n  var sgh4 = -18.0 * ss4 * zes;\n  var sh2 = -2.0 * ss2 * sz22;\n  var sh3 = -2.0 * ss2 * (sz23 - sz21);\n  //  ------------------------ do lunar terms ----------------------\n  var ee2 = 2.0 * s1 * s6;\n  var e3 = 2.0 * s1 * s7;\n  var xi2 = 2.0 * s2 * z12;\n  var xi3 = 2.0 * s2 * (z13 - z11);\n  var xl2 = -2.0 * s3 * z2;\n  var xl3 = -2.0 * s3 * (z3 - z1);\n  var xl4 = -2.0 * s3 * (-21.0 - 9.0 * emsq) * zel;\n  var xgh2 = 2.0 * s4 * z32;\n  var xgh3 = 2.0 * s4 * (z33 - z31);\n  var xgh4 = -18.0 * s4 * zel;\n  var xh2 = -2.0 * s2 * z22;\n  var xh3 = -2.0 * s2 * (z23 - z21);\n  return {\n    snodm: snodm,\n    cnodm: cnodm,\n    sinim: sinim,\n    cosim: cosim,\n    sinomm: sinomm,\n    cosomm: cosomm,\n    day: day,\n    e3: e3,\n    ee2: ee2,\n    em: em,\n    emsq: emsq,\n    gam: gam,\n    peo: peo,\n    pgho: pgho,\n    pho: pho,\n    pinco: pinco,\n    plo: plo,\n    rtemsq: rtemsq,\n    se2: se2,\n    se3: se3,\n    sgh2: sgh2,\n    sgh3: sgh3,\n    sgh4: sgh4,\n    sh2: sh2,\n    sh3: sh3,\n    si2: si2,\n    si3: si3,\n    sl2: sl2,\n    sl3: sl3,\n    sl4: sl4,\n    s1: s1,\n    s2: s2,\n    s3: s3,\n    s4: s4,\n    s5: s5,\n    s6: s6,\n    s7: s7,\n    ss1: ss1,\n    ss2: ss2,\n    ss3: ss3,\n    ss4: ss4,\n    ss5: ss5,\n    ss6: ss6,\n    ss7: ss7,\n    sz1: sz1,\n    sz2: sz2,\n    sz3: sz3,\n    sz11: sz11,\n    sz12: sz12,\n    sz13: sz13,\n    sz21: sz21,\n    sz22: sz22,\n    sz23: sz23,\n    sz31: sz31,\n    sz32: sz32,\n    sz33: sz33,\n    xgh2: xgh2,\n    xgh3: xgh3,\n    xgh4: xgh4,\n    xh2: xh2,\n    xh3: xh3,\n    xi2: xi2,\n    xi3: xi3,\n    xl2: xl2,\n    xl3: xl3,\n    xl4: xl4,\n    nm: nm,\n    z1: z1,\n    z2: z2,\n    z3: z3,\n    z11: z11,\n    z12: z12,\n    z13: z13,\n    z21: z21,\n    z22: z22,\n    z23: z23,\n    z31: z31,\n    z32: z32,\n    z33: z33,\n    zmol: zmol,\n    zmos: zmos\n  };\n}\n\n/*-----------------------------------------------------------------------------\n *\n *                           procedure dsinit\n *\n *  this procedure provides deep space contributions to mean motion dot due\n *    to geopotential resonance with half day and one day orbits.\n *\n *  author        : david vallado                  719-573-2600   28 jun 2005\n *\n *  inputs        :\n *    cosim, sinim-\n *    emsq        - eccentricity squared\n *    argpo       - argument of perigee\n *    s1, s2, s3, s4, s5      -\n *    ss1, ss2, ss3, ss4, ss5 -\n *    sz1, sz3, sz11, sz13, sz21, sz23, sz31, sz33 -\n *    t           - time\n *    tc          -\n *    gsto        - greenwich sidereal time                   rad\n *    mo          - mean anomaly\n *    mdot        - mean anomaly dot (rate)\n *    no          - mean motion\n *    nodeo       - right ascension of ascending node\n *    nodedot     - right ascension of ascending node dot (rate)\n *    xpidot      -\n *    z1, z3, z11, z13, z21, z23, z31, z33 -\n *    eccm        - eccentricity\n *    argpm       - argument of perigee\n *    inclm       - inclination\n *    mm          - mean anomaly\n *    xn          - mean motion\n *    nodem       - right ascension of ascending node\n *\n *  outputs       :\n *    em          - eccentricity\n *    argpm       - argument of perigee\n *    inclm       - inclination\n *    mm          - mean anomaly\n *    nm          - mean motion\n *    nodem       - right ascension of ascending node\n *    irez        - flag for resonance           0-none, 1-one day, 2-half day\n *    atime       -\n *    d2201, d2211, d3210, d3222, d4410, d4422, d5220, d5232, d5421, d5433    -\n *    dedt        -\n *    didt        -\n *    dmdt        -\n *    dndt        -\n *    dnodt       -\n *    domdt       -\n *    del1, del2, del3        -\n *    ses  , sghl , sghs , sgs  , shl  , shs  , sis  , sls\n *    theta       -\n *    xfact       -\n *    xlamo       -\n *    xli         -\n *    xni\n *\n *  locals        :\n *    ainv2       -\n *    aonv        -\n *    cosisq      -\n *    eoc         -\n *    f220, f221, f311, f321, f322, f330, f441, f442, f522, f523, f542, f543  -\n *    g200, g201, g211, g300, g310, g322, g410, g422, g520, g521, g532, g533  -\n *    sini2       -\n *    temp        -\n *    temp1       -\n *    theta       -\n *    xno2        -\n *\n *  coupling      :\n *    getgravconst\n *\n *  references    :\n *    hoots, roehrich, norad spacetrack report #3 1980\n *    hoots, norad spacetrack report #6 1986\n *    hoots, schumacher and glover 2004\n *    vallado, crawford, hujsak, kelso  2006\n ----------------------------------------------------------------------------*/\nfunction dsinit(options) {\n  var cosim = options.cosim,\n    argpo = options.argpo,\n    s1 = options.s1,\n    s2 = options.s2,\n    s3 = options.s3,\n    s4 = options.s4,\n    s5 = options.s5,\n    sinim = options.sinim,\n    ss1 = options.ss1,\n    ss2 = options.ss2,\n    ss3 = options.ss3,\n    ss4 = options.ss4,\n    ss5 = options.ss5,\n    sz1 = options.sz1,\n    sz3 = options.sz3,\n    sz11 = options.sz11,\n    sz13 = options.sz13,\n    sz21 = options.sz21,\n    sz23 = options.sz23,\n    sz31 = options.sz31,\n    sz33 = options.sz33,\n    t = options.t,\n    tc = options.tc,\n    gsto = options.gsto,\n    mo = options.mo,\n    mdot = options.mdot,\n    no = options.no,\n    nodeo = options.nodeo,\n    nodedot = options.nodedot,\n    xpidot = options.xpidot,\n    z1 = options.z1,\n    z3 = options.z3,\n    z11 = options.z11,\n    z13 = options.z13,\n    z21 = options.z21,\n    z23 = options.z23,\n    z31 = options.z31,\n    z33 = options.z33,\n    ecco = options.ecco,\n    eccsq = options.eccsq;\n  var emsq = options.emsq,\n    em = options.em,\n    argpm = options.argpm,\n    inclm = options.inclm,\n    mm = options.mm,\n    nm = options.nm,\n    nodem = options.nodem,\n    irez = options.irez,\n    atime = options.atime,\n    d2201 = options.d2201,\n    d2211 = options.d2211,\n    d3210 = options.d3210,\n    d3222 = options.d3222,\n    d4410 = options.d4410,\n    d4422 = options.d4422,\n    d5220 = options.d5220,\n    d5232 = options.d5232,\n    d5421 = options.d5421,\n    d5433 = options.d5433,\n    dedt = options.dedt,\n    didt = options.didt,\n    dmdt = options.dmdt,\n    dnodt = options.dnodt,\n    domdt = options.domdt,\n    del1 = options.del1,\n    del2 = options.del2,\n    del3 = options.del3,\n    xfact = options.xfact,\n    xlamo = options.xlamo,\n    xli = options.xli,\n    xni = options.xni;\n  var f220;\n  var f221;\n  var f311;\n  var f321;\n  var f322;\n  var f330;\n  var f441;\n  var f442;\n  var f522;\n  var f523;\n  var f542;\n  var f543;\n  var g200;\n  var g201;\n  var g211;\n  var g300;\n  var g310;\n  var g322;\n  var g410;\n  var g422;\n  var g520;\n  var g521;\n  var g532;\n  var g533;\n  var sini2;\n  var temp;\n  var temp1;\n  var xno2;\n  var ainv2;\n  var aonv;\n  var cosisq;\n  var eoc;\n  var q22 = 1.7891679e-6;\n  var q31 = 2.1460748e-6;\n  var q33 = 2.2123015e-7;\n  var root22 = 1.7891679e-6;\n  var root44 = 7.3636953e-9;\n  var root54 = 2.1765803e-9;\n  // eslint-disable-next-line no-loss-of-precision\n  var rptim = 4.37526908801129966e-3; // equates to 7.29211514668855e-5 rad/sec\n  var root32 = 3.7393792e-7;\n  var root52 = 1.1428639e-7;\n  var znl = 1.5835218e-4;\n  var zns = 1.19459e-5;\n  // -------------------- deep space initialization ------------\n  irez = 0;\n  if (nm < 0.0052359877 && nm > 0.0034906585) {\n    irez = 1;\n  }\n  if (nm >= 8.26e-3 && nm <= 9.24e-3 && em >= 0.5) {\n    irez = 2;\n  }\n  // ------------------------ do solar terms -------------------\n  var ses = ss1 * zns * ss5;\n  var sis = ss2 * zns * (sz11 + sz13);\n  var sls = -zns * ss3 * (sz1 + sz3 - 14.0 - 6.0 * emsq);\n  var sghs = ss4 * zns * (sz31 + sz33 - 6.0);\n  var shs = -zns * ss2 * (sz21 + sz23);\n  // sgp4fix for 180 deg incl\n  if (inclm < 5.2359877e-2 || inclm > pi - 5.2359877e-2) {\n    shs = 0.0;\n  }\n  if (sinim !== 0.0) {\n    shs /= sinim;\n  }\n  var sgs = sghs - cosim * shs;\n  // ------------------------- do lunar terms ------------------\n  dedt = ses + s1 * znl * s5;\n  didt = sis + s2 * znl * (z11 + z13);\n  dmdt = sls - znl * s3 * (z1 + z3 - 14.0 - 6.0 * emsq);\n  var sghl = s4 * znl * (z31 + z33 - 6.0);\n  var shll = -znl * s2 * (z21 + z23);\n  // sgp4fix for 180 deg incl\n  if (inclm < 5.2359877e-2 || inclm > pi - 5.2359877e-2) {\n    shll = 0.0;\n  }\n  domdt = sgs + sghl;\n  dnodt = shs;\n  if (sinim !== 0.0) {\n    domdt -= cosim / sinim * shll;\n    dnodt += shll / sinim;\n  }\n  // ----------- calculate deep space resonance effects --------\n  var dndt = 0.0;\n  var theta = (gsto + tc * rptim) % twoPi;\n  em += dedt * t;\n  inclm += didt * t;\n  argpm += domdt * t;\n  nodem += dnodt * t;\n  mm += dmdt * t;\n  // sgp4fix for negative inclinations\n  // the following if statement should be commented out\n  // if (inclm < 0.0)\n  // {\n  //   inclm  = -inclm;\n  //   argpm  = argpm - pi;\n  //   nodem = nodem + pi;\n  // }\n  // -------------- initialize the resonance terms -------------\n  if (irez !== 0) {\n    aonv = Math.pow(nm / xke, x2o3);\n    // ---------- geopotential resonance for 12 hour orbits ------\n    if (irez === 2) {\n      cosisq = cosim * cosim;\n      var emo = em;\n      em = ecco;\n      var emsqo = emsq;\n      emsq = eccsq;\n      eoc = em * emsq;\n      g201 = -0.306 - (em - 0.64) * 0.440;\n      if (em <= 0.65) {\n        g211 = 3.616 - 13.2470 * em + 16.2900 * emsq;\n        g310 = -19.302 + 117.3900 * em - 228.4190 * emsq + 156.5910 * eoc;\n        g322 = -18.9068 + 109.7927 * em - 214.6334 * emsq + 146.5816 * eoc;\n        g410 = -41.122 + 242.6940 * em - 471.0940 * emsq + 313.9530 * eoc;\n        g422 = -146.407 + 841.8800 * em - 1629.014 * emsq + 1083.4350 * eoc;\n        g520 = -532.114 + 3017.977 * em - 5740.032 * emsq + 3708.2760 * eoc;\n      } else {\n        g211 = -72.099 + 331.819 * em - 508.738 * emsq + 266.724 * eoc;\n        g310 = -346.844 + 1582.851 * em - 2415.925 * emsq + 1246.113 * eoc;\n        g322 = -342.585 + 1554.908 * em - 2366.899 * emsq + 1215.972 * eoc;\n        g410 = -1052.797 + 4758.686 * em - 7193.992 * emsq + 3651.957 * eoc;\n        g422 = -3581.690 + 16178.110 * em - 24462.770 * emsq + 12422.520 * eoc;\n        if (em > 0.715) {\n          g520 = -5149.66 + 29936.92 * em - 54087.36 * emsq + 31324.56 * eoc;\n        } else {\n          g520 = 1464.74 - 4664.75 * em + 3763.64 * emsq;\n        }\n      }\n      if (em < 0.7) {\n        g533 = -919.22770 + 4988.6100 * em - 9064.7700 * emsq + 5542.21 * eoc;\n        g521 = -822.71072 + 4568.6173 * em - 8491.4146 * emsq + 5337.524 * eoc;\n        g532 = -853.66600 + 4690.2500 * em - 8624.7700 * emsq + 5341.4 * eoc;\n      } else {\n        g533 = -37995.780 + 161616.52 * em - 229838.20 * emsq + 109377.94 * eoc;\n        g521 = -51752.104 + 218913.95 * em - 309468.16 * emsq + 146349.42 * eoc;\n        g532 = -40023.880 + 170470.89 * em - 242699.48 * emsq + 115605.82 * eoc;\n      }\n      sini2 = sinim * sinim;\n      f220 = 0.75 * (1.0 + 2.0 * cosim + cosisq);\n      f221 = 1.5 * sini2;\n      f321 = 1.875 * sinim * (1.0 - 2.0 * cosim - 3.0 * cosisq);\n      f322 = -1.875 * sinim * (1.0 + 2.0 * cosim - 3.0 * cosisq);\n      f441 = 35.0 * sini2 * f220;\n      f442 = 39.3750 * sini2 * sini2;\n      f522 = 9.84375 * sinim * (sini2 * (1.0 - 2.0 * cosim - 5.0 * cosisq) + 0.33333333 * (-2.0 + 4.0 * cosim + 6.0 * cosisq));\n      f523 = sinim * (4.92187512 * sini2 * (-2.0 - 4.0 * cosim + 10.0 * cosisq) + 6.56250012 * (1.0 + 2.0 * cosim - 3.0 * cosisq));\n      f542 = 29.53125 * sinim * (2.0 - 8.0 * cosim + cosisq * (-12.0 + 8.0 * cosim + 10.0 * cosisq));\n      f543 = 29.53125 * sinim * (-2.0 - 8.0 * cosim + cosisq * (12.0 + 8.0 * cosim - 10.0 * cosisq));\n      xno2 = nm * nm;\n      ainv2 = aonv * aonv;\n      temp1 = 3.0 * xno2 * ainv2;\n      temp = temp1 * root22;\n      d2201 = temp * f220 * g201;\n      d2211 = temp * f221 * g211;\n      temp1 *= aonv;\n      temp = temp1 * root32;\n      d3210 = temp * f321 * g310;\n      d3222 = temp * f322 * g322;\n      temp1 *= aonv;\n      temp = 2.0 * temp1 * root44;\n      d4410 = temp * f441 * g410;\n      d4422 = temp * f442 * g422;\n      temp1 *= aonv;\n      temp = temp1 * root52;\n      d5220 = temp * f522 * g520;\n      d5232 = temp * f523 * g532;\n      temp = 2.0 * temp1 * root54;\n      d5421 = temp * f542 * g521;\n      d5433 = temp * f543 * g533;\n      xlamo = (mo + nodeo + nodeo - (theta + theta)) % twoPi;\n      xfact = mdot + dmdt + 2.0 * (nodedot + dnodt - rptim) - no;\n      em = emo;\n      emsq = emsqo;\n    }\n    //  ---------------- synchronous resonance terms --------------\n    if (irez === 1) {\n      g200 = 1.0 + emsq * (-2.5 + 0.8125 * emsq);\n      g310 = 1.0 + 2.0 * emsq;\n      g300 = 1.0 + emsq * (-6.0 + 6.60937 * emsq);\n      f220 = 0.75 * (1.0 + cosim) * (1.0 + cosim);\n      f311 = 0.9375 * sinim * sinim * (1.0 + 3.0 * cosim) - 0.75 * (1.0 + cosim);\n      f330 = 1.0 + cosim;\n      f330 *= 1.875 * f330 * f330;\n      del1 = 3.0 * nm * nm * aonv * aonv;\n      del2 = 2.0 * del1 * f220 * g200 * q22;\n      del3 = 3.0 * del1 * f330 * g300 * q33 * aonv;\n      del1 = del1 * f311 * g310 * q31 * aonv;\n      xlamo = (mo + nodeo + argpo - theta) % twoPi;\n      xfact = mdot + xpidot + dmdt + domdt + dnodt - (no + rptim);\n    }\n    //  ------------ for sgp4, initialize the integrator ----------\n    xli = xlamo;\n    xni = no;\n    atime = 0.0;\n    nm = no + dndt;\n  }\n  return {\n    em: em,\n    argpm: argpm,\n    inclm: inclm,\n    mm: mm,\n    nm: nm,\n    nodem: nodem,\n    irez: irez,\n    atime: atime,\n    d2201: d2201,\n    d2211: d2211,\n    d3210: d3210,\n    d3222: d3222,\n    d4410: d4410,\n    d4422: d4422,\n    d5220: d5220,\n    d5232: d5232,\n    d5421: d5421,\n    d5433: d5433,\n    dedt: dedt,\n    didt: didt,\n    dmdt: dmdt,\n    dndt: dndt,\n    dnodt: dnodt,\n    domdt: domdt,\n    del1: del1,\n    del2: del2,\n    del3: del3,\n    xfact: xfact,\n    xlamo: xlamo,\n    xli: xli,\n    xni: xni\n  };\n}\n\n/* -----------------------------------------------------------------------------\n *\n *                           function gstime\n *\n *  this function finds the greenwich sidereal time.\n *\n *  author        : david vallado                  719-573-2600    1 mar 2001\n *\n *  inputs          description                    range / units\n *    jdut1       - julian date in ut1             days from 4713 bc\n *\n *  outputs       :\n *    gstime      - greenwich sidereal time        0 to 2pi rad\n *\n *  locals        :\n *    temp        - temporary variable for doubles   rad\n *    tut1        - julian centuries from the\n *                  jan 1, 2000 12 h epoch (ut1)\n *\n *  coupling      :\n *    none\n *\n *  references    :\n *    vallado       2004, 191, eq 3-45\n * --------------------------------------------------------------------------- */\nfunction gstimeInternal(jdut1) {\n  var tut1 = (jdut1 - 2451545.0) / 36525.0;\n  var temp = -6.2e-6 * tut1 * tut1 * tut1 + 0.093104 * tut1 * tut1 + (876600.0 * 3600 + 8640184.812866) * tut1 + 67310.54841; // # sec\n  temp = temp * deg2rad / 240.0 % twoPi; // 360/86400 = 1/240, to deg, to rad\n  //  ------------------------ check quadrants ---------------------\n  if (temp < 0.0) {\n    temp += twoPi;\n  }\n  return temp;\n}\nfunction gstime(first, month, day, hour, minute, second, millisecond) {\n  if (first instanceof Date) {\n    return gstimeInternal(jday(first));\n  } else if (month !== undefined) {\n    return gstimeInternal(jday(first, month, day, hour, minute, second, millisecond));\n  } else {\n    return gstimeInternal(first);\n  }\n}\n\n/*-----------------------------------------------------------------------------\n *\n *                           procedure initl\n *\n *  this procedure initializes the sgp4 propagator. all the initialization is\n *    consolidated here instead of having multiple loops inside other routines.\n *\n *  author        : david vallado                  719-573-2600   28 jun 2005\n *\n *  inputs        :\n *    ecco        - eccentricity                           0.0 - 1.0\n *    epoch       - epoch time in days from jan 0, 1950. 0 hr\n *    inclo       - inclination of satellite\n *    no          - mean motion of satellite\n *    satn        - satellite number\n *\n *  outputs       :\n *    ainv        - 1.0 / a\n *    ao          - semi major axis\n *    con41       -\n *    con42       - 1.0 - 5.0 cos(i)\n *    cosio       - cosine of inclination\n *    cosio2      - cosio squared\n *    eccsq       - eccentricity squared\n *    method      - flag for deep space                    'd', 'n'\n *    omeosq      - 1.0 - ecco * ecco\n *    posq        - semi-parameter squared\n *    rp          - radius of perigee\n *    rteosq      - square root of (1.0 - ecco*ecco)\n *    sinio       - sine of inclination\n *    gsto        - gst at time of observation               rad\n *    no          - mean motion of satellite\n *\n *  locals        :\n *    ak          -\n *    d1          -\n *    del         -\n *    adel        -\n *    po          -\n *\n *  coupling      :\n *    getgravconst\n *    gstime      - find greenwich sidereal time from the julian date\n *\n *  references    :\n *    hoots, roehrich, norad spacetrack report #3 1980\n *    hoots, norad spacetrack report #6 1986\n *    hoots, schumacher and glover 2004\n *    vallado, crawford, hujsak, kelso  2006\n ----------------------------------------------------------------------------*/\nfunction initl(options) {\n  var ecco = options.ecco,\n    epoch = options.epoch,\n    inclo = options.inclo,\n    opsmode = options.opsmode;\n  var no = options.no;\n  // sgp4fix use old way of finding gst\n  // ----------------------- earth constants ---------------------\n  // sgp4fix identify constants and allow alternate values\n  // ------------- calculate auxillary epoch quantities ----------\n  var eccsq = ecco * ecco;\n  var omeosq = 1.0 - eccsq;\n  var rteosq = Math.sqrt(omeosq);\n  var cosio = Math.cos(inclo);\n  var cosio2 = cosio * cosio;\n  // ------------------ un-kozai the mean motion -----------------\n  var ak = Math.pow(xke / no, x2o3);\n  var d1 = 0.75 * j2 * (3.0 * cosio2 - 1.0) / (rteosq * omeosq);\n  var delPrime = d1 / (ak * ak);\n  var adel = ak * (1.0 - delPrime * delPrime - delPrime * (1.0 / 3.0 + 134.0 * delPrime * delPrime / 81.0));\n  delPrime = d1 / (adel * adel);\n  no /= 1.0 + delPrime;\n  var ao = Math.pow(xke / no, x2o3);\n  var sinio = Math.sin(inclo);\n  var po = ao * omeosq;\n  var con42 = 1.0 - 5.0 * cosio2;\n  var con41 = -con42 - cosio2 - cosio2;\n  var ainv = 1.0 / ao;\n  var posq = po * po;\n  var rp = ao * (1.0 - ecco);\n  var method = 'n';\n  //  sgp4fix modern approach to finding sidereal time\n  var gsto;\n  if (opsmode === 'a') {\n    //  sgp4fix use old way of finding gst\n    //  count integer number of days from 0 jan 1970\n    var ts70 = epoch - 7305.0;\n    var ds70 = Math.floor(ts70 + 1.0e-8);\n    var tfrac = ts70 - ds70;\n    //  find greenwich location at epoch\n    var c1 = 1.72027916940703639e-2; // eslint-disable-line no-loss-of-precision\n    var thgr70 = 1.7321343856509374; // eslint-disable-line no-loss-of-precision\n    var fk5r = 5.07551419432269442e-15; // eslint-disable-line no-loss-of-precision\n    var c1p2p = c1 + twoPi;\n    gsto = (thgr70 + c1 * ds70 + c1p2p * tfrac + ts70 * ts70 * fk5r) % twoPi;\n    if (gsto < 0.0) {\n      gsto += twoPi;\n    }\n  } else {\n    gsto = gstime(epoch + 2433281.5);\n  }\n  return {\n    no: no,\n    method: method,\n    ainv: ainv,\n    ao: ao,\n    con41: con41,\n    con42: con42,\n    cosio: cosio,\n    cosio2: cosio2,\n    eccsq: eccsq,\n    omeosq: omeosq,\n    posq: posq,\n    rp: rp,\n    rteosq: rteosq,\n    sinio: sinio,\n    gsto: gsto\n  };\n}\n\n/*-----------------------------------------------------------------------------\n *\n *                           procedure dspace\n *\n *  this procedure provides deep space contributions to mean elements for\n *    perturbing third body.  these effects have been averaged over one\n *    revolution of the sun and moon.  for earth resonance effects, the\n *    effects have been averaged over no revolutions of the satellite.\n *    (mean motion)\n *\n *  author        : david vallado                  719-573-2600   28 jun 2005\n *\n *  inputs        :\n *    d2201, d2211, d3210, d3222, d4410, d4422, d5220, d5232, d5421, d5433 -\n *    dedt        -\n *    del1, del2, del3  -\n *    didt        -\n *    dmdt        -\n *    dnodt       -\n *    domdt       -\n *    irez        - flag for resonance           0-none, 1-one day, 2-half day\n *    argpo       - argument of perigee\n *    argpdot     - argument of perigee dot (rate)\n *    t           - time\n *    tc          -\n *    gsto        - gst\n *    xfact       -\n *    xlamo       -\n *    no          - mean motion\n *    atime       -\n *    em          - eccentricity\n *    ft          -\n *    argpm       - argument of perigee\n *    inclm       - inclination\n *    xli         -\n *    mm          - mean anomaly\n *    xni         - mean motion\n *    nodem       - right ascension of ascending node\n *\n *  outputs       :\n *    atime       -\n *    em          - eccentricity\n *    argpm       - argument of perigee\n *    inclm       - inclination\n *    xli         -\n *    mm          - mean anomaly\n *    xni         -\n *    nodem       - right ascension of ascending node\n *    dndt        -\n *    nm          - mean motion\n *\n *  locals        :\n *    delt        -\n *    ft          -\n *    theta       -\n *    x2li        -\n *    x2omi       -\n *    xl          -\n *    xldot       -\n *    xnddt       -\n *    xndt        -\n *    xomi        -\n *\n *  coupling      :\n *    none        -\n *\n *  references    :\n *    hoots, roehrich, norad spacetrack report #3 1980\n *    hoots, norad spacetrack report #6 1986\n *    hoots, schumacher and glover 2004\n *    vallado, crawford, hujsak, kelso  2006\n ----------------------------------------------------------------------------*/\nfunction dspace(options) {\n  var irez = options.irez,\n    d2201 = options.d2201,\n    d2211 = options.d2211,\n    d3210 = options.d3210,\n    d3222 = options.d3222,\n    d4410 = options.d4410,\n    d4422 = options.d4422,\n    d5220 = options.d5220,\n    d5232 = options.d5232,\n    d5421 = options.d5421,\n    d5433 = options.d5433,\n    dedt = options.dedt,\n    del1 = options.del1,\n    del2 = options.del2,\n    del3 = options.del3,\n    didt = options.didt,\n    dmdt = options.dmdt,\n    dnodt = options.dnodt,\n    domdt = options.domdt,\n    argpo = options.argpo,\n    argpdot = options.argpdot,\n    t = options.t,\n    tc = options.tc,\n    gsto = options.gsto,\n    xfact = options.xfact,\n    xlamo = options.xlamo,\n    no = options.no;\n  var atime = options.atime,\n    em = options.em,\n    argpm = options.argpm,\n    inclm = options.inclm,\n    xli = options.xli,\n    mm = options.mm,\n    xni = options.xni,\n    nodem = options.nodem,\n    nm = options.nm;\n  var fasx2 = 0.13130908;\n  var fasx4 = 2.8843198;\n  var fasx6 = 0.37448087;\n  var g22 = 5.7686396;\n  var g32 = 0.95240898;\n  var g44 = 1.8014998;\n  var g52 = 1.0508330;\n  var g54 = 4.4108898;\n  // eslint-disable-next-line no-loss-of-precision\n  var rptim = 4.37526908801129966e-3; // equates to 7.29211514668855e-5 rad/sec\n  var stepp = 720.0;\n  var stepn = -720.0;\n  var step2 = 259200.0;\n  var delt;\n  var x2li;\n  var x2omi;\n  var xl;\n  var xldot;\n  var xnddt;\n  var xndt;\n  var xomi;\n  var dndt = 0.0;\n  var ft = 0.0;\n  //  ----------- calculate deep space resonance effects -----------\n  var theta = (gsto + tc * rptim) % twoPi;\n  em += dedt * t;\n  inclm += didt * t;\n  argpm += domdt * t;\n  nodem += dnodt * t;\n  mm += dmdt * t;\n  // sgp4fix for negative inclinations\n  // the following if statement should be commented out\n  // if (inclm < 0.0)\n  // {\n  //   inclm = -inclm;\n  //   argpm = argpm - pi;\n  //   nodem = nodem + pi;\n  // }\n  /* - update resonances : numerical (euler-maclaurin) integration - */\n  /* ------------------------- epoch restart ----------------------  */\n  //   sgp4fix for propagator problems\n  //   the following integration works for negative time steps and periods\n  //   the specific changes are unknown because the original code was so convoluted\n  // sgp4fix take out atime = 0.0 and fix for faster operation\n  if (irez !== 0) {\n    //  sgp4fix streamline check\n    if (atime === 0.0 || t * atime <= 0.0 || Math.abs(t) < Math.abs(atime)) {\n      atime = 0.0;\n      xni = no;\n      xli = xlamo;\n    }\n    // sgp4fix move check outside loop\n    if (t > 0.0) {\n      delt = stepp;\n    } else {\n      delt = stepn;\n    }\n    var iretn = 381; // added for do loop\n    while (iretn === 381) {\n      //  ------------------- dot terms calculated -------------\n      //  ----------- near - synchronous resonance terms -------\n      if (irez !== 2) {\n        xndt = del1 * Math.sin(xli - fasx2) + del2 * Math.sin(2.0 * (xli - fasx4)) + del3 * Math.sin(3.0 * (xli - fasx6));\n        xldot = xni + xfact;\n        xnddt = del1 * Math.cos(xli - fasx2) + 2.0 * del2 * Math.cos(2.0 * (xli - fasx4)) + 3.0 * del3 * Math.cos(3.0 * (xli - fasx6));\n        xnddt *= xldot;\n      } else {\n        // --------- near - half-day resonance terms --------\n        xomi = argpo + argpdot * atime;\n        x2omi = xomi + xomi;\n        x2li = xli + xli;\n        xndt = d2201 * Math.sin(x2omi + xli - g22) + d2211 * Math.sin(xli - g22) + d3210 * Math.sin(xomi + xli - g32) + d3222 * Math.sin(-xomi + xli - g32) + d4410 * Math.sin(x2omi + x2li - g44) + d4422 * Math.sin(x2li - g44) + d5220 * Math.sin(xomi + xli - g52) + d5232 * Math.sin(-xomi + xli - g52) + d5421 * Math.sin(xomi + x2li - g54) + d5433 * Math.sin(-xomi + x2li - g54);\n        xldot = xni + xfact;\n        xnddt = d2201 * Math.cos(x2omi + xli - g22) + d2211 * Math.cos(xli - g22) + d3210 * Math.cos(xomi + xli - g32) + d3222 * Math.cos(-xomi + xli - g32) + d5220 * Math.cos(xomi + xli - g52) + d5232 * Math.cos(-xomi + xli - g52) + 2.0 * (d4410 * Math.cos(x2omi + x2li - g44) + d4422 * Math.cos(x2li - g44) + d5421 * Math.cos(xomi + x2li - g54) + d5433 * Math.cos(-xomi + x2li - g54));\n        xnddt *= xldot;\n      }\n      //  ----------------------- integrator -------------------\n      //  sgp4fix move end checks to end of routine\n      if (Math.abs(t - atime) >= stepp) {\n        iretn = 381;\n      } else {\n        ft = t - atime;\n        iretn = 0;\n      }\n      if (iretn === 381) {\n        xli += xldot * delt + xndt * step2;\n        xni += xndt * delt + xnddt * step2;\n        atime += delt;\n      }\n    }\n    nm = xni + xndt * ft + xnddt * ft * ft * 0.5;\n    xl = xli + xldot * ft + xndt * ft * ft * 0.5;\n    if (irez !== 1) {\n      mm = xl - 2.0 * nodem + 2.0 * theta;\n      dndt = nm - no;\n    } else {\n      mm = xl - nodem - argpm + theta;\n      dndt = nm - no;\n    }\n    nm = no + dndt;\n  }\n  return {\n    atime: atime,\n    em: em,\n    argpm: argpm,\n    inclm: inclm,\n    xli: xli,\n    mm: mm,\n    xni: xni,\n    nodem: nodem,\n    dndt: dndt,\n    nm: nm\n  };\n}\n\nvar SatRecError;\n(function (SatRecError) {\n  /**\n   * No error, propagation for the last supplied date is successful\n   */\n  SatRecError[SatRecError[\"None\"] = 0] = \"None\";\n  /**\n   * Mean eccentricity is out of range 0 ≤ e < 1\n   */\n  SatRecError[SatRecError[\"MeanEccentricityOutOfRange\"] = 1] = \"MeanEccentricityOutOfRange\";\n  /**\n   * Mean motion has fallen below zero.\n   */\n  SatRecError[SatRecError[\"MeanMotionBelowZero\"] = 2] = \"MeanMotionBelowZero\";\n  /**\n   * Perturbed eccentricity is out of range 0 ≤ e < 1\n   */\n  SatRecError[SatRecError[\"PerturbedEccentricityOutOfRange\"] = 3] = \"PerturbedEccentricityOutOfRange\";\n  /**\n   * Length of the orbit’s semi-latus rectum has fallen below zero.\n   */\n  SatRecError[SatRecError[\"SemiLatusRectumBelowZero\"] = 4] = \"SemiLatusRectumBelowZero\";\n  // 5 is not used\n  /**\n   * Orbit has decayed: the computed position is underground.\n   */\n  SatRecError[SatRecError[\"Decayed\"] = 6] = \"Decayed\";\n})(SatRecError || (SatRecError = {}));\n\n/*----------------------------------------------------------------------------\n *\n *                             procedur