如何将小时和分钟格式的浮点数求和？

var arr = [0.15, 0.2, 3.45, 0.4, 2, 0.3, 5.2, 1, 1.4, 1.1, 2.4, 1, 3.4]
    
var sum = 0.0;
    
arr.forEach(function(item) {
  console.log(sum);
  sum += parseFloat(item);
});

// converts a pseudo-float of the form hh.mm into an integer number of minutes
// robust against floating-point roundoff errors, also works for negative numbers
function hhMmToMinutes(x) {
  const hhmm = Math.round(100 * x)  // convert hh.mm -> hhmm
  return 60 * Math.trunc(hhmm / 100) + (hhmm % 100)
}

// convert minutes back to hh.mm pseudo-float format
// use minutesToHhMm(minutes).toFixed(2) if you want trailing zeros
function minutesToHhMm(minutes) {
  return Math.trunc(minutes / 60) + (minutes % 60) / 100
}

const arr = [0.15, 0.2, 3.45, 0.4, 2, 0.3, 5.2, 1, 1.4, 1.1, 2.4, 1, 3.4]

let sum = 0
console.log( arr.map(hhMmToMinutes).map(x => sum += x).map(minutesToHhMm) )

console.log(Math.trunc(100 * 0.29))  // you'd think this would be 29...

// We got this after simple addition
// Now we want to change it into 4.2
sample = 3.8

// Now here are the minutes that the float currently shows
minutes = (sample % 1) * 100

// And the hours
hours = Math.floor(sample)

// Here are the number of hours that can be reduced from minutes
AddHours = Math.floor(minutes / 60)

// Adding them to the hours count
hours += AddHours

// Reducing mintues
minutes %= 60

// Finally formatting hour and minutes into your format
final = hours + (minutes / 100.0)
console.log(final)

const resultObj = [0.35, 3.45].reduce((a, e) => {
  const [hours, minutes] = e.toString().split('.');
  a.h += +hours;
  a.m += (+(minutes.padEnd(2, 0)) || 0); 
  return a;
}, {h: 0, m: 0});


const result = resultObj.h + Math.floor(resultObj.m / 60) + ((resultObj.m % 60) / 100);
console.log(result);

var arr = [0.15, 0.2, 3.45, 0.4, 2, 0.3, 5.2, 1, 1.4, 1.1, 2.4, 1, 3.4];

function add(arr) {
  var hm = arr
    .map(v => [Math.floor(v), (v % 1).toFixed(2) * 100])  // Map the array to values having [hours, minutes]
    .reduce((t, v) => { //  reduce the array of [h, m] to a single object having total hours and minutes
      t = {
        h: t.h + v[0],
        m: t.m + v[1]
      };
      return t;
    }, {
      h: 0,
      m: 0
    });

  // final result would be = 
  // total hours from above
  // + hours from total minutes (retrived using Math.floor(hm.m / 60)) 
  // + minutes (after converting it to be a decimal part)
  return (parseFloat(hm.h + Math.floor(hm.m / 60)) + parseFloat(((hm.m % 60) / 100).toFixed(2))).toFixed(2);
}

// adding `arr` array
console.log(add(arr));

// adding 0.35+3.45
console.log(add([0.35, 3.45]));

var arr = [0.15, 0.2, 3.45, 0.4, 2, 0.3, 5.2, 1, 1.4, 1.1, 2.4, 1, 3.4];
let hoursTally = 0;
let minutesTally = 0;

for(var i = 0; i < arr.length; i++) {
  // Convert the float to a string, as floats can be a pain to add together
  let time = arr[i].toString().split('.');
  // Tally up the hours.
  hoursTally += parseInt(time[0]);
  // Tally up the minutes;
  let minute = time[1];
  if(minute) {
    // We do this so we add 20 minutes, not 2 minutes
    if(minute.length < 2) {
      minutesTally += parseInt(minute) * 10;
    } else {
      minutesTally += parseInt(minute);
    }
    // If the minutesTally is greater than 60, add an hour to hours
    if(minutesTally >= 60) {
      hoursTally++;
      // Set the minutesTally to be the remainder after dividing by 60
      minutesTally = minutesTally % 60;
    }
  }
  console.log(hoursTally + "." + minutesTally);
}

const arr = [0.15, 0.2, 3.45, 0.4, 2, 0.3, 5.2, 1, 1.4, 1.1, 2.4, 1, 3.4]

const reducer = (acc, curr) => {
  acc = `${acc}`.split('.').length > 1 ? acc : `${acc}.0`;
  curr = `${curr}`.split('.').length > 1 ? curr : `${curr}.0`;
  let hours = parseStrAndSum(true, `${acc}`.split('.')[0], `${curr}`.split('.')[0]);
  let minute = parseStrAndSum(false, `${acc}`.split('.')[1], `${curr}`.split('.')[1]);
  hours = parseInt(hours / 1) + parseInt(minute / 60);
  minute = minute % 60;
  console.log(`${acc} + ${curr} = ${hours}.${minute}`);
  return `${hours}.${minute}`;
}

const parseStrAndSum = (is_hours, ...strs) => {
  let result = 0;
  strs.forEach(function(number) {
    if (!is_hours) {
      number = number.length == 1 ? `${number}0` : number;
    }
    result += parseInt(number);
  });
  return result;
};

arr.reduce(reducer);