Skip to main content

Build an array of dates with cumulative sum

I am building a dashboard to compare the cumulative spending of the current month against the cumulative spending of the last month. This looks like this: Expected output

As you can see below, my code is very naive and I am pretty sure it can be improved. Right now I loop many times over the arrays to fill each date of currentMonthSpend with the appropriate sum of transactions that happened on this date, cumulated with the previous values ...

Would you be able to guide me with a smarter way of doing it? The current logic is the following:

  • Create the array date objects (with x = date and y = cumulative sum)
  • I already have my list of transactions (with date and amount for each entry which can obviously happen at the same date of another entry)
  • First, I iterate through currentMonthTransactions, I find the corresponding date in currentMonthSpend and I increment the y property
  • Then I iterate through currentMonthSpend and I apply a cumulative sum

Thanks for your help!

const startOfCurrentMonth = moment().startOf("month");
const endOfCurrentMonth = moment().endOf("month");
const currentMonthSpend = [];

while (startOfCurrentMonth.isSameOrBefore(endOfCurrentMonth)) {
  currentMonthSpend.push({ x: startOfCurrentMonth.format("YYYY-MM-DD"), y: 0 });
  startOfCurrentMonth.add(1, "days");
}

const currentMonthTransactions = [
  {
    date: "2022-10-03",
    amount: -50,
  },
  {
    date: "2022-10-04",
    amount: -100,
  },
  {
    date: "2022-10-05",
    amount: -20,
  },
  {
    date: "2022-10-05",
    amount: -10,
  },
  {
    date: "2022-10-08",
    amount: -40,
  },
];

for (let i = 0; i < currentMonthTransactions.length; i++) {
  let index = currentMonthSpend.findIndex((item) => {
    return item.x === currentMonthTransactions[i].date;
  });
  if (index !== -1) {
    currentMonthSpend[index].y += currentMonthTransactions[i].amount;
  }
}

const result = currentMonthSpend.map((obj, index, self) => {
  if (index == 0) {
    obj.y = 0;
    return obj;
  }
  const prevO = self[index - 1];
  obj.y += prevO.y;
  obj.y = +obj.y.toFixed(2);
  return obj;
});

console.log(result)
<script src="https://cdnjs.cloudflare.com/ajax/libs/moment.js/2.29.4/moment.min.js"></script>
Via Active questions tagged javascript - Stack Overflow https://ift.tt/wGkElhJ

Comments

Popular posts from this blog

Confusion between commands.Bot and discord.Client | Which one should I use?

Whenever you look at YouTube tutorials or code from this website there is a real variation. Some developers use client = discord.Client(intents=intents) while the others use bot = commands.Bot(command_prefix="something", intents=intents) . Now I know slightly about the difference but I get errors from different places from my code when I use either of them and its confusing. Especially since there has a few changes over the years in discord.py it is hard to find the real difference. I tried sticking to discord.Client then I found that there are more features in commands.Bot . Then I found errors when using commands.Bot . An example of this is: When I try to use commands.Bot client = commands.Bot(command_prefix=">",intents=intents) async def load(): for filename in os.listdir("./Cogs"): if filename.endswith(".py"): client.load_extension(f"Cogs.{filename[:-3]}") The above doesnt giveany response from my Cogs ...

How to show number of registered users in Laravel based on usertype?

i'm trying to display data from the database in the admin dashboard i used this: <?php use Illuminate\Support\Facades\DB; $users = DB::table('users')->count(); echo $users; ?> and i have successfully get the correct data from the database but what if i want to display a specific data for example in this user table there is "usertype" that specify if the user is normal user or admin i want to user the same code above but to display a specific usertype i tried this: <?php use Illuminate\Support\Facades\DB; $users = DB::table('users')->count()->WHERE usertype =admin; echo $users; ?> but it didn't work, what am i doing wrong? source https://stackoverflow.com/questions/68199726/how-to-show-number-of-registered-users-in-laravel-based-on-usertype

Why is my reports service not connecting?

I am trying to pull some data from a Postgres database using Node.js and node-postures but I can't figure out why my service isn't connecting. my routes/index.js file: const express = require('express'); const router = express.Router(); const ordersCountController = require('../controllers/ordersCountController'); const ordersController = require('../controllers/ordersController'); const weeklyReportsController = require('../controllers/weeklyReportsController'); router.get('/orders_count', ordersCountController); router.get('/orders', ordersController); router.get('/weekly_reports', weeklyReportsController); module.exports = router; My controllers/weeklyReportsController.js file: const weeklyReportsService = require('../services/weeklyReportsService'); const weeklyReportsController = async (req, res) => { try { const data = await weeklyReportsService; res.json({data}) console...