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Selection from JSON - javascript

I recently started learning JavaScript and faced a task that I can't complete in any way, every time I get the wrong data that I need
There is an object that contains data on banking transactions, I need to make a selection and form a new object using filter, map or reduce:
We assume that the initial balance on the card = 0.
Output the TOP 3 months with the largest number of operations by month.
Formalize it as a task_1(arr) function, where arr is the source array with data
for all months.
Output format:
[
{ year: 2019, month: 11, opsCount: 27 },
{ year: 2019, month: 10, opsCount: 26 },
{ year: 2019, month: 8, opsCount: 24 }
]
Output statistics for the end of the specified month.
monthmonthBalance - own balance by month = The amount of all
deposits minus the amount of all debits
montWithdrawal – total cash withdrawal amount
withdrawalRate – the share of the total amount of debits from the total amount of
deposits per month.
rank – user status calculated by the formula:
Gold if withdrawalRate < 0.15.
Silver if withdrawalRate < 0.3.
Bronze in all other cases.
Formalize it as a task_2(year, month, arr) function, where year, month is the desired one
month, and arr is the original array with all the data by month.
Output format:
{
date: '2019-01-31’,
monthBalance: 3829,
monthWithrawal: 33800,
withdrawalRate: 0.3133
rank: 'Bronze’
}
Calculate statistics from task 2 for all months of the period.
Add a field to each month
totalBalance - cumulative balance = Own balance for the
month + Balance for the cumulative balance for the previous month.
Output format:
[
{
date: '2019-01-31’,
monthBalance: 3829,
totalBalance: 3829,
monthWithrawal: 33800,
withdrawalRate: 0.3133
rank: ’Bronze'
},
...
]
Formalize it as a task_3(arr) function, where arr is the source array with data.
JSON with data:
[
{ "year": 2019, "month": 1, "day": 1, "type": "replenishment", "amount": 79817 },
{ "year": 2019, "month": 1, "day": 3, "type": "payment", "amount": 11334 },
{ "year": 2019, "month": 1, "day": 5, "type": "withdrawal", "amount": 26700 },
{ "year": 2019, "month": 1, "day": 5, "type": "payment", "amount": 15475 },
{ "year": 2019, "month": 1, "day": 6, "type": "payment", "amount": 4818 },
{ "year": 2019, "month": 1, "day": 6, "type": "payment", "amount": 1893 },
{ "year": 2019, "month": 1, "day": 7, "type": "payment", "amount": 3844 },
{ "year": 2019, "month": 1, "day": 7, "type": "withdrawal", "amount": 3100 },
{ "year": 2019, "month": 1, "day": 7, "type": "payment", "amount": 3230 },
{ "year": 2019, "month": 1, "day": 7, "type": "payment", "amount": 2427 },
{ "year": 2019, "month": 1, "day": 9, "type": "replenishment", "amount": 15835 },
{ "year": 2019, "month": 1, "day": 10, "type": "payment", "amount": 9670 },
{ "year": 2019, "month": 1, "day": 11, "type": "payment", "amount": 582 },
{ "year": 2019, "month": 1, "day": 11, "type": "withdrawal", "amount": 1100 },
{ "year": 2019, "month": 1, "day": 11, "type": "replenishment", "amount": 5971 },
{ "year": 2019, "month": 1, "day": 12, "type": "payment", "amount": 173 },
{ "year": 2019, "month": 1, "day": 14, "type": "withdrawal", "amount": 1500 },
{ "year": 2019, "month": 1, "day": 14, "type": "payment", "amount": 3641 },
{ "year": 2019, "month": 1, "day": 16, "type": "payment", "amount": 4669 },
{ "year": 2019, "month": 1, "day": 18, "type": "payment", "amount": 2460 },
{ "year": 2019, "month": 1, "day": 19, "type": "payment", "amount": 1307 },
{ "year": 2019, "month": 1, "day": 20, "type": "withdrawal", "amount": 1400 },
{ "year": 2019, "month": 1, "day": 21, "type": "payment", "amount": 952 },
{ "year": 2019, "month": 1, "day": 21, "type": "payment", "amount": 561 },
{ "year": 2019, "month": 1, "day": 21, "type": "replenishment", "amount": 6236 },
{ "year": 2019, "month": 1, "day": 22, "type": "payment", "amount": 888 },
{ "year": 2019, "month": 1, "day": 22, "type": "payment", "amount": 2306 },
{ "year": 2019, "month": 2, "day": 1, "type": "replenishment", "amount": 84839 },
{ "year": 2019, "month": 2, "day": 1, "type": "withdrawal", "amount": 27700 },
{ "year": 2019, "month": 2, "day": 1, "type": "payment", "amount": 11145 },
{ "year": 2019, "month": 2, "day": 2, "type": "payment", "amount": 4075 },
{ "year": 2019, "month": 2, "day": 4, "type": "withdrawal", "amount": 10900 },
{ "year": 2019, "month": 2, "day": 6, "type": "payment", "amount": 10537 },
{ "year": 2019, "month": 2, "day": 6, "type": "payment", "amount": 6001 },
{ "year": 2019, "month": 2, "day": 7, "type": "withdrawal", "amount": 7300 },
{ "year": 2019, "month": 2, "day": 10, "type": "withdrawal", "amount": 1500 },
{ "year": 2019, "month": 2, "day": 10, "type": "payment", "amount": 3584 },
{ "year": 2019, "month": 2, "day": 11, "type": "payment", "amount": 701 },
{ "year": 2019, "month": 3, "day": 1, "type": "replenishment", "amount": 84771 },
{ "year": 2019, "month": 3, "day": 3, "type": "withdrawal", "amount": 22700 },
{ "year": 2019, "month": 3, "day": 5, "type": "payment", "amount": 12352 },
{ "year": 2019, "month": 3, "day": 8, "type": "payment", "amount": 2795 },
{ "year": 2019, "month": 3, "day": 11, "type": "withdrawal", "amount": 16600 },
{ "year": 2019, "month": 3, "day": 11, "type": "replenishment", "amount": 4141 },
{ "year": 2019, "month": 3, "day": 11, "type": "payment", "amount": 9854 },
{ "year": 2019, "month": 3, "day": 13, "type": "withdrawal", "amount": 1200 },
{ "year": 2019, "month": 3, "day": 14, "type": "payment", "amount": 11573 },
{ "year": 2019, "month": 3, "day": 14, "type": "payment", "amount": 5138 },
{ "year": 2019, "month": 3, "day": 15, "type": "payment", "amount": 731 },
{ "year": 2019, "month": 3, "day": 17, "type": "payment", "amount": 5053 },
{ "year": 2019, "month": 3, "day": 19, "type": "withdrawal", "amount": 400 },
{ "year": 2019, "month": 3, "day": 20, "type": "payment", "amount": 1745 },
{ "year": 2019, "month": 3, "day": 20, "type": "payment", "amount": 602 },
{ "year": 2019, "month": 3, "day": 21, "type": "payment", "amount": 178 },
{ "year": 2019, "month": 3, "day": 22, "type": "payment", "amount": 353 },
{ "year": 2019, "month": 3, "day": 23, "type": "payment", "amount": 837 },
{ "year": 2019, "month": 3, "day": 23, "type": "payment", "amount": 330 },
{ "year": 2019, "month": 3, "day": 23, "type": "payment", "amount": 799 },
{ "year": 2019, "month": 3, "day": 24, "type": "payment", "amount": 294 },
{ "year": 2019, "month": 3, "day": 24, "type": "payment", "amount": 260 },
{ "year": 2019, "month": 3, "day": 25, "type": "withdrawal", "amount": 200 },
{ "year": 2019, "month": 4, "day": 1, "type": "replenishment", "amount": 88656 },
{ "year": 2019, "month": 4, "day": 4, "type": "payment", "amount": 37852 },
{ "year": 2019, "month": 4, "day": 7, "type": "payment", "amount": 9365 },
{ "year": 2019, "month": 4, "day": 8, "type": "payment", "amount": 16701 },
{ "year": 2019, "month": 4, "day": 11, "type": "payment", "amount": 8979 },
{ "year": 2019, "month": 4, "day": 11, "type": "payment", "amount": 1971 },
{ "year": 2019, "month": 4, "day": 13, "type": "payment", "amount": 1261 },
{ "year": 2019, "month": 4, "day": 13, "type": "withdrawal", "amount": 800 },
{ "year": 2019, "month": 4, "day": 15, "type": "payment", "amount": 5553 },
{ "year": 2019, "month": 4, "day": 17, "type": "payment", "amount": 2593 },
{ "year": 2019, "month": 4, "day": 18, "type": "replenishment", "amount": 6915 },
{ "year": 2019, "month": 4, "day": 19, "type": "replenishment", "amount": 17647 },
{ "year": 2019, "month": 4, "day": 21, "type": "payment", "amount": 13814 },
{ "year": 2019, "month": 4, "day": 22, "type": "payment", "amount": 2707 },
{ "year": 2019, "month": 4, "day": 22, "type": "withdrawal", "amount": 1300 },
{ "year": 2019, "month": 4, "day": 22, "type": "withdrawal", "amount": 2900 },
{ "year": 2019, "month": 4, "day": 23, "type": "replenishment", "amount": 10709 },
{ "year": 2019, "month": 4, "day": 23, "type": "payment", "amount": 686 },
{ "year": 2019, "month": 4, "day": 23, "type": "withdrawal", "amount": 5100 },
{ "year": 2019, "month": 4, "day": 23, "type": "payment", "amount": 3830 },
{ "year": 2019, "month": 5, "day": 1, "type": "replenishment", "amount": 59877 },
{ "year": 2019, "month": 5, "day": 2, "type": "payment", "amount": 14095 },
{ "year": 2019, "month": 5, "day": 5, "type": "payment", "amount": 10858 },
{ "year": 2019, "month": 5, "day": 8, "type": "payment", "amount": 9412 },
{ "year": 2019, "month": 5, "day": 11, "type": "replenishment", "amount": 6892 },
{ "year": 2019, "month": 5, "day": 11, "type": "payment", "amount": 17541 },
{ "year": 2019, "month": 5, "day": 11, "type": "payment", "amount": 2666 },
{ "year": 2019, "month": 5, "day": 11, "type": "payment", "amount": 3935 },
{ "year": 2019, "month": 5, "day": 12, "type": "withdrawal", "amount": 2600 },
{ "year": 2019, "month": 5, "day": 14, "type": "payment", "amount": 2096 },
{ "year": 2019, "month": 5, "day": 14, "type": "replenishment", "amount": 2733 },
{ "year": 2019, "month": 5, "day": 15, "type": "replenishment", "amount": 538 },
{ "year": 2019, "month": 5, "day": 15, "type": "payment", "amount": 5324 },
{ "year": 2019, "month": 5, "day": 15, "type": "payment", "amount": 2490 },
{ "year": 2019, "month": 5, "day": 15, "type": "payment", "amount": 3510 },
{ "year": 2019, "month": 5, "day": 17, "type": "withdrawal", "amount": 300 },
{ "year": 2019, "month": 5, "day": 17, "type": "payment", "amount": 133 },
{ "year": 2019, "month": 6, "day": 1, "type": "replenishment", "amount": 89064 },
{ "year": 2019, "month": 6, "day": 2, "type": "payment", "amount": 7613 },
{ "year": 2019, "month": 6, "day": 2, "type": "payment", "amount": 33742 },
{ "year": 2019, "month": 6, "day": 5, "type": "withdrawal", "amount": 7200 },
{ "year": 2019, "month": 6, "day": 6, "type": "payment", "amount": 15125 },
{ "year": 2019, "month": 6, "day": 9, "type": "payment", "amount": 3379 },
{ "year": 2019, "month": 6, "day": 10, "type": "payment", "amount": 1260 },
{ "year": 2019, "month": 6, "day": 12, "type": "payment", "amount": 11066 },
{ "year": 2019, "month": 6, "day": 12, "type": "replenishment", "amount": 7050 },
{ "year": 2019, "month": 6, "day": 12, "type": "payment", "amount": 7531 },
{ "year": 2019, "month": 6, "day": 13, "type": "payment", "amount": 4776 },
{ "year": 2019, "month": 6, "day": 13, "type": "replenishment", "amount": 4456 },
{ "year": 2019, "month": 6, "day": 14, "type": "replenishment", "amount": 7998 },
{ "year": 2019, "month": 6, "day": 16, "type": "payment", "amount": 2437 },
{ "year": 2019, "month": 6, "day": 16, "type": "replenishment", "amount": 11729 },
{ "year": 2019, "month": 6, "day": 18, "type": "payment", "amount": 11216 },
{ "year": 2019, "month": 6, "day": 19, "type": "payment", "amount": 3420 },
{ "year": 2019, "month": 6, "day": 19, "type": "payment", "amount": 1339 },
{ "year": 2019, "month": 6, "day": 20, "type": "payment", "amount": 5578 },
{ "year": 2019, "month": 6, "day": 21, "type": "withdrawal", "amount": 1600 },
{ "year": 2019, "month": 6, "day": 21, "type": "withdrawal", "amount": 400 },
{ "year": 2019, "month": 7, "day": 1, "type": "replenishment", "amount": 51749 },
{ "year": 2019, "month": 7, "day": 2, "type": "payment", "amount": 2875 },
{ "year": 2019, "month": 7, "day": 2, "type": "payment", "amount": 10315 },
{ "year": 2019, "month": 7, "day": 5, "type": "payment", "amount": 18501 },
{ "year": 2019, "month": 7, "day": 5, "type": "payment", "amount": 12728 },
{ "year": 2019, "month": 7, "day": 7, "type": "payment", "amount": 4505 },
{ "year": 2019, "month": 7, "day": 8, "type": "payment", "amount": 2758 },
{ "year": 2019, "month": 7, "day": 8, "type": "payment", "amount": 60 },
{ "year": 2019, "month": 7, "day": 10, "type": "withdrawal", "amount": 1100 },
{ "year": 2019, "month": 7, "day": 12, "type": "withdrawal", "amount": 1000 },
{ "year": 2019, "month": 7, "day": 13, "type": "payment", "amount": 151 },
{ "year": 2019, "month": 8, "day": 1, "type": "replenishment", "amount": 85156 },
{ "year": 2019, "month": 8, "day": 1, "type": "payment", "amount": 33978 },
{ "year": 2019, "month": 8, "day": 2, "type": "payment", "amount": 6548 },
{ "year": 2019, "month": 8, "day": 3, "type": "payment", "amount": 5909 },
{ "year": 2019, "month": 8, "day": 6, "type": "payment", "amount": 2326 },
{ "year": 2019, "month": 8, "day": 6, "type": "payment", "amount": 17798 },
{ "year": 2019, "month": 8, "day": 9, "type": "replenishment", "amount": 10770 },
{ "year": 2019, "month": 8, "day": 10, "type": "withdrawal", "amount": 7400 },
{ "year": 2019, "month": 8, "day": 12, "type": "payment", "amount": 6065 },
{ "year": 2019, "month": 8, "day": 14, "type": "withdrawal", "amount": 900 },
{ "year": 2019, "month": 8, "day": 14, "type": "withdrawal", "amount": 1400 },
{ "year": 2019, "month": 8, "day": 14, "type": "payment", "amount": 4673 },
{ "year": 2019, "month": 8, "day": 15, "type": "payment", "amount": 960 },
{ "year": 2019, "month": 8, "day": 15, "type": "payment", "amount": 1085 },
{ "year": 2019, "month": 8, "day": 17, "type": "payment", "amount": 3723 },
{ "year": 2019, "month": 8, "day": 17, "type": "payment", "amount": 2522 },
{ "year": 2019, "month": 8, "day": 19, "type": "replenishment", "amount": 2496 },
{ "year": 2019, "month": 8, "day": 20, "type": "payment", "amount": 876 },
{ "year": 2019, "month": 8, "day": 20, "type": "payment", "amount": 2504 },
{ "year": 2019, "month": 8, "day": 21, "type": "payment", "amount": 826 },
{ "year": 2019, "month": 8, "day": 22, "type": "payment", "amount": 768 },
{ "year": 2019, "month": 8, "day": 23, "type": "withdrawal", "amount": 700 },
{ "year": 2019, "month": 8, "day": 23, "type": "payment", "amount": 190 },
{ "year": 2019, "month": 8, "day": 24, "type": "payment", "amount": 235 },
{ "year": 2019, "month": 9, "day": 1, "type": "replenishment", "amount": 95512 },
{ "year": 2019, "month": 9, "day": 3, "type": "payment", "amount": 26758 },
{ "year": 2019, "month": 9, "day": 3, "type": "replenishment", "amount": 8377 },
{ "year": 2019, "month": 9, "day": 4, "type": "payment", "amount": 30865 },
{ "year": 2019, "month": 9, "day": 4, "type": "withdrawal", "amount": 12800 },
{ "year": 2019, "month": 9, "day": 7, "type": "payment", "amount": 10518 },
{ "year": 2019, "month": 9, "day": 8, "type": "payment", "amount": 11007 },
{ "year": 2019, "month": 9, "day": 10, "type": "payment", "amount": 5613 },
{ "year": 2019, "month": 9, "day": 10, "type": "withdrawal", "amount": 1700 },
{ "year": 2019, "month": 9, "day": 12, "type": "payment", "amount": 2237 },
{ "year": 2019, "month": 9, "day": 14, "type": "payment", "amount": 885 },
{ "year": 2019, "month": 9, "day": 14, "type": "payment", "amount": 977 },
{ "year": 2019, "month": 9, "day": 15, "type": "payment", "amount": 766 },
{ "year": 2019, "month": 9, "day": 17, "type": "payment", "amount": 360 },
{ "year": 2019, "month": 9, "day": 18, "type": "payment", "amount": 116 },
{ "year": 2019, "month": 9, "day": 18, "type": "withdrawal", "amount": 200 },
{ "year": 2019, "month": 9, "day": 19, "type": "payment", "amount": 115 },
{ "year": 2019, "month": 9, "day": 20, "type": "payment", "amount": 50 },
{ "year": 2019, "month": 9, "day": 21, "type": "payment", "amount": 32 },
{ "year": 2019, "month": 10, "day": 1, "type": "replenishment", "amount": 90475 },
{ "year": 2019, "month": 10, "day": 1, "type": "replenishment", "amount": 8845 },
{ "year": 2019, "month": 10, "day": 2, "type": "payment", "amount": 7121 },
{ "year": 2019, "month": 10, "day": 3, "type": "payment", "amount": 27955 },
{ "year": 2019, "month": 10, "day": 3, "type": "payment", "amount": 23079 },
{ "year": 2019, "month": 10, "day": 4, "type": "payment", "amount": 5948 },
{ "year": 2019, "month": 10, "day": 7, "type": "withdrawal", "amount": 4400 },
{ "year": 2019, "month": 10, "day": 8, "type": "payment", "amount": 9677 },
{ "year": 2019, "month": 10, "day": 9, "type": "payment", "amount": 3912 },
{ "year": 2019, "month": 10, "day": 9, "type": "replenishment", "amount": 3870 },
{ "year": 2019, "month": 10, "day": 9, "type": "payment", "amount": 6949 },
{ "year": 2019, "month": 10, "day": 10, "type": "withdrawal", "amount": 3400 },
{ "year": 2019, "month": 10, "day": 10, "type": "replenishment", "amount": 7471 },
{ "year": 2019, "month": 10, "day": 10, "type": "payment", "amount": 5962 },
{ "year": 2019, "month": 10, "day": 10, "type": "payment", "amount": 4990 },
{ "year": 2019, "month": 10, "day": 10, "type": "withdrawal", "amount": 3000 },
{ "year": 2019, "month": 10, "day": 11, "type": "withdrawal", "amount": 200 },
{ "year": 2019, "month": 10, "day": 12, "type": "withdrawal", "amount": 1300 },
{ "year": 2019, "month": 10, "day": 13, "type": "payment", "amount": 986 },
{ "year": 2019, "month": 10, "day": 14, "type": "replenishment", "amount": 4225 },
{ "year": 2019, "month": 10, "day": 15, "type": "withdrawal", "amount": 900 },
{ "year": 2019, "month": 10, "day": 17, "type": "payment", "amount": 864 },
{ "year": 2019, "month": 10, "day": 17, "type": "withdrawal", "amount": 1000 },
{ "year": 2019, "month": 10, "day": 18, "type": "payment", "amount": 801 },
{ "year": 2019, "month": 10, "day": 19, "type": "withdrawal", "amount": 300 },
{ "year": 2019, "month": 10, "day": 20, "type": "payment", "amount": 530 },
{ "year": 2019, "month": 11, "day": 1, "type": "replenishment", "amount": 80285 },
{ "year": 2019, "month": 11, "day": 3, "type": "payment", "amount": 38155 },
{ "year": 2019, "month": 11, "day": 6, "type": "payment", "amount": 10260 },
{ "year": 2019, "month": 11, "day": 9, "type": "payment", "amount": 11013 },
{ "year": 2019, "month": 11, "day": 10, "type": "payment", "amount": 1232 },
{ "year": 2019, "month": 11, "day": 12, "type": "withdrawal", "amount": 5100 },
{ "year": 2019, "month": 11, "day": 12, "type": "payment", "amount": 1192 },
{ "year": 2019, "month": 11, "day": 13, "type": "withdrawal", "amount": 4500 },
{ "year": 2019, "month": 11, "day": 14, "type": "replenishment", "amount": 4304 },
{ "year": 2019, "month": 11, "day": 15, "type": "withdrawal", "amount": 700 },
{ "year": 2019, "month": 11, "day": 15, "type": "replenishment", "amount": 15857 },
{ "year": 2019, "month": 11, "day": 17, "type": "payment", "amount": 9134 },
{ "year": 2019, "month": 11, "day": 19, "type": "payment", "amount": 8090 },
{ "year": 2019, "month": 11, "day": 20, "type": "payment", "amount": 2117 },
{ "year": 2019, "month": 11, "day": 20, "type": "withdrawal", "amount": 2700 },
{ "year": 2019, "month": 11, "day": 21, "type": "withdrawal", "amount": 2200 },
{ "year": 2019, "month": 11, "day": 21, "type": "payment", "amount": 258 },
{ "year": 2019, "month": 11, "day": 21, "type": "withdrawal", "amount": 1200 },
{ "year": 2019, "month": 11, "day": 21, "type": "payment", "amount": 1966 },
{ "year": 2019, "month": 11, "day": 21, "type": "withdrawal", "amount": 200 },
{ "year": 2019, "month": 11, "day": 21, "type": "payment", "amount": 493 },
{ "year": 2019, "month": 11, "day": 21, "type": "payment", "amount": 396 },
{ "year": 2019, "month": 11, "day": 21, "type": "withdrawal", "amount": 200 },
{ "year": 2019, "month": 11, "day": 21, "type": "payment", "amount": 134 },
{ "year": 2019, "month": 11, "day": 22, "type": "replenishment", "amount": 4815 },
{ "year": 2019, "month": 11, "day": 22, "type": "withdrawal", "amount": 500 },
{ "year": 2019, "month": 11, "day": 23, "type": "payment", "amount": 1793 },
{ "year": 2019, "month": 12, "day": 1, "type": "replenishment", "amount": 93524 },
{ "year": 2019, "month": 12, "day": 2, "type": "payment", "amount": 44289 },
{ "year": 2019, "month": 12, "day": 2, "type": "payment", "amount": 7724 },
{ "year": 2019, "month": 12, "day": 4, "type": "payment", "amount": 9420 },
{ "year": 2019, "month": 12, "day": 4, "type": "withdrawal", "amount": 3200 },
{ "year": 2019, "month": 12, "day": 4, "type": "payment", "amount": 651 },
{ "year": 2019, "month": 12, "day": 6, "type": "payment", "amount": 9259 },
{ "year": 2019, "month": 12, "day": 6, "type": "withdrawal", "amount": 5700 },
{ "year": 2019, "month": 12, "day": 7, "type": "payment", "amount": 1298 },
{ "year": 2019, "month": 12, "day": 9, "type": "payment", "amount": 3108 },
{ "year": 2019, "month": 12, "day": 11, "type": "withdrawal", "amount": 4300 },
{ "year": 2019, "month": 12, "day": 13, "type": "withdrawal", "amount": 200 },
{ "year": 2019, "month": 12, "day": 13, "type": "replenishment", "amount": 9096 },
{ "year": 2019, "month": 12, "day": 14, "type": "payment", "amount": 7205 },
{ "year": 2019, "month": 12, "day": 16, "type": "payment", "amount": 658 },
{ "year": 2019, "month": 12, "day": 17, "type": "replenishment", "amount": 9654 }
]
First, for the task_1, I get an object that contains values by the key "month":
var arr1 = ops.map(function(item){
return item.month
})
Then I find the sum of the unique values in the resulting array:
quantity var = {};
for (var i = 0; i <arr1.length; i++){
quantity [arr1[i]] = 1 + (quantity [arr1[i]]|/ 0);
}
and I get the counts object in the following form:
counts
{1: 27, 2: 11, 3: 23, 4: 20, 5: 17, 6: 21, 7: 11, 8: 24, 9: 19, 10: 26, 11: 27, 12: 16}
After that, I sort to find the 3 maximum values:
function findMax 3(obj){
var res = [-1,-1,-1];
for (let key in obj){
res[3] = obj[key];
res.sort(function(a,b){return b-a});
}
res.pop();
return res;
}
console.log(findMax3(counts));
In the console I get the following:
[27, 27, 26]
but at the same time, I no longer know the index of the months to which these values relate
Thank you for your answers!

To solve these problems here is the hint "GroupBy using reduce"
As for task1
function task_1(arr) {
// Dictionary of Month to Object.
const groupedByMonth = arr.reduce(function (acc, currentValue) {
let groupKey = currentValue.month;
if (!acc[groupKey]) {
acc[groupKey] = {
year: currentValue.year,
month: currentValue.month,
opsCount: 0
};
}
acc[groupKey].opsCount += 1; // ++
return acc;
}, {});
// Sort by opsCount
function opsSort(a, b) { return b.opsCount - a.opsCount };
return Object
.values(groupedByMonth) // Array of Values
.sort(opsSort)
.slice(0, 3) // Top 3
}
Once you understand how task 1 is solved, task 2 becomes a bit simpler
Solution for Task 2
function getEndOfMonth(year, month) {
const date = new Date(year, month, 0);
let monthStr = "";
if (month < 10) {
monthStr += "0";
}
monthStr += month;
return year + "-" + monthStr + "-" + date.getDate();
}
function getRank(rate) {
if (rate < 0.15)
return 'Gold';
if (rate < 0.3)
return 'Gold';
return 'Bronze';
}
function task_2(arr) {
const groupedByMonth = arr.reduce(function (acc, currentValue) {
let groupKey = currentValue.month;
if (!acc[groupKey]) {
acc[groupKey] = {
date: getEndOfMonth(currentValue.year, currentValue.month),
monthWithrawal: 0,
totalDebits: 0,
totalDeposits: 0
};
}
// Based on type calculate value.
if (currentValue.type === "replenishment") {
acc[groupKey].totalDeposits += currentValue.amount;
} else if (currentValue.type === "payment") {
acc[groupKey].totalDebits += currentValue.amount;
} else if (currentValue.type === "withdrawal") {
acc[groupKey].monthWithrawal += currentValue.amount;
}
return acc;
}, {});
return Object
.values(groupedByMonth) // Array of Values
.map(function (ele) {
const withdrawalRate = ele.monthWithrawal / ele.totalDeposits;
return {
date: ele.date,
monthBalance: ele.totalDeposits - ele.totalDebits - ele.monthWithrawal,
monthWithrawal: ele.monthWithrawal,
withdrawalRate,
rank: getRank(withdrawalRate)
};
});
}
if you have solved task 2, task 3 is just adding reduce/map to task2's solution.
function task_3(arr) {
// Assuming that task_2 function is defined.
const task2 = task_2(arr);
// Can be Solved using reduce.
return task2
.map(function (currentValue, index, array) {
const tmp = currentValue;
tmp.totalBalance = tmp.monthBalance;
if (index > 0) { // Not the first element.
tmp.totalBalance += array[index - 1].totalBalance;
}
return tmp;
})
}

Task 1
const task_1 = (arr, top = 3) => {
const ops = arr.reduce((acc, {year, month}) => {
const accByMonth = acc.find((obj) => (obj.month === month));
if (accByMonth) {
accByMonth.opsCount +=1;
} else {
acc.push({ year, month, opsCount: 1 })
}
return acc;
}, []);
const sortedOps = ops.sort(
(obj1, obj2) => (obj2.opsCount - obj1.opsCount)
);
return sortedOps.slice(0, top);
}
console.log(task_1(data));
//[
// { year: 2019, month: 1, opsCount: 27 },
// { year: 2019, month: 11, opsCount: 27 },
// { year: 2019, month: 10, opsCount: 26 }
//]
Task 2
const getTotalByType = (arr, type) => arr
.filter((obj) => obj.type === type)
.reduce((sum, { amount }) => sum + amount, 0);
const getRank = (ratio) =>{
const ranks = [[0.15, 'Gold'], [0.3, 'Silver'], [Infinity, 'Bronze']]
return ranks.find(([ rankRatio ]) => ratio < rankRatio)[1];
}
const task_2 = (year, month, arr) => {
const filteredData = arr.filter((obj) => (obj.year === year) && (obj.month === month));
const maxDay = Math.max(...filteredData.map(({ day }) => day));
const date = new Date(year, month - 1, maxDay).toISOString().split('T')[0];
const monthReplenishment = getTotalByType(filteredData, 'replenishment');
const monthPayment = getTotalByType(filteredData, 'payment');
const monthWithdrawal = getTotalByType(filteredData, 'withdrawal');
const monthBalance = monthReplenishment - monthPayment - monthWithdrawal;
const withdrawalRate = parseFloat((monthWithdrawal / monthReplenishment).toFixed(4));
const rank = getRank(withdrawalRate);
return {
date,
monthBalance,
monthWithdrawal,
withdrawalRate,
rank,
}
};
console.log(task_2(2019, 7, data));
//{
// date: '2019-07-13',
// monthBalance: -2244,
// monthWithdrawal: 2100,
// withdrawalRate: 0.0406,
// rank: 'Gold'
//}
Task 3
const getPeriods = (arr) => arr.
reduce((acc, {year, month}) => {
const isPeriodInAcc = acc.some(
(obj) => (obj.month === month) && (obj.year === year)
);
if (!isPeriodInAcc) {
acc.push({ year, month })
}
return acc;
}, [])
const task_3 = (arr, initialBalance = 0) => {
const periods = getPeriods(arr);
let totalBalance = initialBalance;
return periods.map(({ year, month }) => {
const opsByPeriod = task_2(year, month, arr);
totalBalance += opsByPeriod.monthBalance;
return {...opsByPeriod, totalBalance}
});
}
console.log(task_3(data));
//[
// {
// date: '2019-01-22',
// monthBalance: 3829,
// monthWithdrawal: 33800,
// withdrawalRate: 0.3134,
// rank: 'Bronze',
// totalBalance: 3829
// },
// ...
// {...},
//]

Related

I made a line change via axios.path, but after changes in db.json I constantly need to reload the page. How can I avoid this and make the data update automatically?
const submitEdits = (item) => {
axios.patch(`http://localhost:3004/item/${item.id}`, { text: editingText })
setIdItem(null);
setEditingText('')
}
My db.json
{
"item": [
{
"text": "123123123",
"id": 0,
"data": {
"year": 2012,
"day": 25,
"month": 1
}
},
{
"text": "Поступил в институт",
"id": 1,
"data": {
"year": 2007,
"day": 12,
"month": 4
}
},
{
"id": 2,
"text": "123",
"data": {
"year": 2022,
"day": 16,
"month": 5
}
}
]
}

I am using destructuring to create a start and end time:
const {
startYear: year,
startMonth: month,
startDay: day,
startHour: hour,
startMinute: minute
} = event.start_date_details;
const {
endHour: hour,
endMinute: minute
} = event.end_date_details;
Any ideas?
Events json:
"events": [
{
"id": 518,
"global_id": "wordpress.rguc.co.uk?id=518",
"global_id_lineage": [
"wordpress.rguc.co.uk?id=518"
],
"author": "1",
"status": "publish",
"date": "2017-12-14 12:11:42",
"date_utc": "2017-12-14 12:11:42",
"modified": "2018-01-11 10:04:49",
"modified_utc": "2018-01-11 10:04:49",
"url": "http://wordpress.rguc.co.uk/event/another-one/",
"rest_url": "http://wordpress.rguc.co.uk/wp-json/tribe/events/v1/events/518",
"title": "another one",
"description": "",
"excerpt": "",
"image": false,
"all_day": true,
"start_date": "2018-01-31 00:00:00",
"start_date_details": {
"year": "2018",
"month": "01",
"day": "31",
"hour": "00",
"minutes": "00",
"seconds": "00"
},
"end_date": "2018-01-31 23:59:59",
"end_date_details": {
"year": "2018",
"month": "01",
"day": "31",
"hour": "23",
"minutes": "59",
"seconds": "59"
},
"utc_start_date": "2018-01-31 00:00:00",
"utc_start_date_details": {
"year": "2018",
"month": "01",
"day": "31",
"hour": "00",
"minutes": "00",
"seconds": "00"
},
"utc_end_date": "2018-01-31 23:59:59",
"utc_end_date_details": {
"year": "2018",
"month": "01",
"day": "31",
"hour": "23",
"minutes": "59",
"seconds": "59"
},

The syntax for destructuring (BTW destructing is the wrong term) is different. You need to specify keys you match before colon and variables you declare after colon.
Maybe you wanted:
const {
year: startYear,
month: startMonth,
day: startDay,
hour: startHour,
minutes: startMinute
} = event.start_date_details;
const {
hour: endHour,
minutes: endMinute
} = event.end_date_details;

You're destructuring both event.start_date_details.startHour and event.end_date_details.endHour to const hour. Change it to
const {
start_date_details: {
year: startYear,
month: startMonth,
day: startDay,
hour: startHour,
minutes: startMinute
},
end_date_details: {
hour: endHour,
minutes: endMinute
}
} = event;
so that you have the variable startHour, startMinute, endHour, and endMinute instead mapped from event.(start/end)_date_details.(hour/minutes).
See MDN's Destructuring Assignment - Assigning to new variable names.

Take the array of objects below "toursByHotels" — I want to take this data and get the sum of tours for each object that has the same name (the hotel's name, ie. Marriott, etc).
Is there an easier way in d3 than having to create 5 new arrays with the same names, then sum the tours of those?
var toursByHotel = [
{
"name": "Marriott",
"month": 1,
"tours": 10
},
{
"name": "Marriott",
"month": 2,
"tours": 15
},
{
"name": "Marriott",
"month": 3,
"tours": 8
},
{
"name": "Marriott",
"month": 4,
"tours": 12
},
{
"name": "Marriott",
"month": 5,
"tours": 18
},
{
"name": "Marriott",
"month": 6,
"tours": 25
},
{
"name": "Marriott",
"month": 7,
"tours": 40
},
{
"name": "Marriott",
"month": 8,
"tours": 33
},
{
"name": "Marriott",
"month": 9,
"tours": 25
},
{
"name": "Marriott",
"month": 10,
"tours": 21
},
{
"name": "Marriott",
"month": 11,
"tours": 18
},
{
"name": "Marriott",
"month": 12,
"tours": 14
},
{
"name": "Springhill",
"month": 1,
"tours": 10
},
{
"name": "Springhill",
"month": 2,
"tours": 15
},
{
"name": "Springhill",
"month": 3,
"tours": 8
},
{
"name": "Springhill",
"month": 4,
"tours": 12
},
{
"name": "Springhill",
"month": 5,
"tours": 18
},
{
"name": "Springhill",
"month": 6,
"tours": 25
},
{
"name": "Springhill",
"month": 7,
"tours": 40
},
{
"name": "Springhill",
"month": 8,
"tours": 33
},
{
"name": "Springhill",
"month": 9,
"tours": 25
},
{
"name": "Springhill",
"month": 10,
"tours": 21
},
{
"name": "Springhill",
"month": 11,
"tours": 18
},
{
"name": "Springhill",
"month": 12,
"tours": 14
},
{
"name": "Residence",
"month": 1,
"tours": 10
},
{
"name": "Residence",
"month": 2,
"tours": 15
},
{
"name": "Residence",
"month": 3,
"tours": 8
},
{
"name": "Residence",
"month": 4,
"tours": 12
},
{
"name": "Residence",
"month": 5,
"tours": 18
},
{
"name": "Residence",
"month": 6,
"tours": 25
},
{
"name": "Residence",
"month": 7,
"tours": 40
},
{
"name": "Residence",
"month": 8,
"tours": 33
},
{
"name": "Residence",
"month": 9,
"tours": 25
},
{
"name": "Residence",
"month": 10,
"tours": 21
},
{
"name": "Residence",
"month": 11,
"tours": 18
},
{
"name": "Residence",
"month": 12,
"tours": 14
},
{
"name": "Courtyard",
"month": 1,
"tours": 10
},
{
"name": "Courtyard",
"month": 2,
"tours": 15
},
{
"name": "Courtyard",
"month": 3,
"tours": 8
},
{
"name": "Courtyard",
"month": 4,
"tours": 12
},
{
"name": "Courtyard",
"month": 5,
"tours": 18
},
{
"name": "Courtyard",
"month": 6,
"tours": 25
},
{
"name": "Courtyard",
"month": 7,
"tours": 40
},
{
"name": "Courtyard",
"month": 8,
"tours": 33
},
{
"name": "Courtyard",
"month": 9,
"tours": 25
},
{
"name": "Courtyard",
"month": 10,
"tours": 21
},
{
"name": "Courtyard",
"month": 11,
"tours": 18
},
{
"name": "Courtyard",
"month": 12,
"tours": 14
},
{
"name": "Renaissance",
"month": 1,
"tours": 10
},
{
"name": "Renaissance",
"month": 2,
"tours": 15
},
{
"name": "Renaissance",
"month": 3,
"tours": 8
},
{
"name": "Renaissance",
"month": 4,
"tours": 12
},
{
"name": "Renaissance",
"month": 5,
"tours": 18
},
{
"name": "Renaissance",
"month": 6,
"tours": 25
},
{
"name": "Renaissance",
"month": 7,
"tours": 40
},
{
"name": "Renaissance",
"month": 8,
"tours": 33
},
{
"name": "Renaissance",
"month": 9,
"tours": 25
},
{
"name": "Renaissance",
"month": 10,
"tours": 21
},
{
"name": "Renaissance",
"month": 11,
"tours": 18
},
{
"name": "Renaissance",
"month": 12,
"tours": 14
}
];

You can use reduce and return object where each key is hotel name and value is sum of tours. DEMO
data = data.reduce(function(obj, e) {
obj[e.name] = (obj[e.name] || 0) + e.tours;
return obj;
}, {});
console.log(data)
If you want to get sum and percentage for each hotel you can do it like this DEMO
var result = {}
var total = data.reduce((a, b) => {return a + b.tours }, 0);
data.forEach(function(e) {
if(!this[e.name]) {
this[e.name] = {sum: e.tours, percentage: 0}
result[e.name] = this[e.name];
}
this[e.name].sum += e.tours;
this[e.name].percentage = (this[e.name].sum / total)*100;
}, {});
console.log(result)

Using reduce would be the best way to do this:
Working Example
// lets keep track of the total here:
var total = 0;
var totals = a.reduce(function(curr, next) {
curr[next.name] = (curr[next.name] || 0) + next.tours;
// increment total here:
total += next.tours;
return curr;
}, {});
for (var hotel in totals) {
var obj = {};
obj.name = totals[hotel];
obj.percentage = (totals[hotel] / total) * 100 + '%';
totals[hotel] = obj;
}
MDN docs on .reduce

I have a JSON like below
var data = [
{ "year": 2013, "month": 10, "week": 41, "changes": 1590 },
{ "year": 2013, "month": 10, "week": 42, "changes": 0 },
{ "year": 2013, "month": 10, "week": 43, "changes": 2008 },
{ "year": 2013, "month": 10, "week": 44, "changes": 3900 },
{ "year": 2014, "month": 10, "week": 41, "changes": 1052 },
{ "year": 2014, "month": 10, "week": 42, "changes": 0 },
{ "year": 2014, "month": 10, "week": 43, "changes": 10122 },
{ "year": 2014, "month": 10, "week": 44, "changes": 1461 },
{ "year": 2015, "month": 10, "week": 41, "changes": 682 },
{ "year": 2015, "month": 10, "week": 42, "changes": 0 },
{ "year": 2015, "month": 10, "week": 43, "changes": 244 },
{ "year": 2015, "month": 10, "week": 44, "changes": 21 }
];
and i want to generate this JSON some thing like that
var firstYear = "2013";
var secondYear = "2014";
var thildYear = "2015";
var sampleData = [
{ "week": 41, "firstYear": 1590, "secondYear": 1052, "thildYear": 682 },
{ "week": 42, "firstYear": 0, "secondYear": 0, "thildYear": 0 },
{ "week": 43, "firstYear": 2008, "secondYear": 10122, "thildYear": 244 },
{ "week": 44, "firstYear": 858, "secondYear": 1461, "thildYear": 21 }
];
i write a code but it does't work
var jsonObjdata = [];
var yearExist = "";
var weekExist = "";
var SampleRequestBody = {};
$.each(data, function (key, value) {
if (value.year != yearExist) {
SampleRequestBody.week = value.week;
SampleRequestBody.firstYear = value.changes;
yearExist = value.year;
}
else if (value.year == yearExist && value.week == weekExist + 1) {
SampleRequestBody.secondYear = value.changes;
}
else if (value.year == yearExist && value.week == weekExist + 1) {
SampleRequestBody.thildYear = value.changes;
jsonObjdata.push(SampleRequestBody);
}
});
Can you please help me ?

Here is another take at it using array.prototype.reduce:
var weeks = [], flatData;
flatData = data.reduce(function(outData, obj) {
var tmp = {}, prop = 'year' + obj.year;
if ((idx = weeks.indexOf(obj.week)) >= 0) {
outData[idx][prop] = obj.changes;
} else {
weeks.push(obj.week);
tmp['week'] = obj.week;
tmp[prop] = obj.changes;
outData.push(tmp);
}
return outData;
}, []);
It will return you an object array like this:
week year2013 year2014 year2015
---- -------- -------- --------
41 1590 1052 682
42 0 0 0
43 2008 10122 244
44 3900 1461 21
Demo Fiddle: http://jsfiddle.net/abhitalks/kLg5f1wk/
(check console)
Demo Snippet:
(check console)
var data = [
{ "year": 2013, "month": 10, "week": 41, "changes": 1590 },
{ "year": 2013, "month": 10, "week": 42, "changes": 0 },
{ "year": 2013, "month": 10, "week": 43, "changes": 2008 },
{ "year": 2013, "month": 10, "week": 44, "changes": 3900 },
{ "year": 2014, "month": 10, "week": 41, "changes": 1052 },
{ "year": 2014, "month": 10, "week": 42, "changes": 0 },
{ "year": 2014, "month": 10, "week": 43, "changes": 10122 },
{ "year": 2014, "month": 10, "week": 44, "changes": 1461 },
{ "year": 2015, "month": 10, "week": 41, "changes": 682 },
{ "year": 2015, "month": 10, "week": 42, "changes": 0 },
{ "year": 2015, "month": 10, "week": 43, "changes": 244 },
{ "year": 2015, "month": 10, "week": 44, "changes": 21 }
], weeks = [], flatData;
flatData = data.reduce(function(outData, obj) {
var tmp = {}, prop = 'year' + obj.year;
if ((idx = weeks.indexOf(obj.week)) >= 0) {
outData[idx][prop] = obj.changes;
} else {
weeks.push(obj.week);
tmp['week'] = obj.week;
tmp[prop] = obj.changes;
outData.push(tmp);
}
return outData;
}, []);
console.table(flatData);

I suggest to use Array.prototype.forEach and Array.prototype.map for creating a temporary object and the later result array.
var data = [{ "year": 2013, "month": 10, "week": 41, "changes": 1590 }, { "year": 2013, "month": 10, "week": 42, "changes": 0 }, { "year": 2013, "month": 10, "week": 43, "changes": 2008 }, { "year": 2013, "month": 10, "week": 44, "changes": 3900 }, { "year": 2014, "month": 10, "week": 41, "changes": 1052 }, { "year": 2014, "month": 10, "week": 42, "changes": 0 }, { "year": 2014, "month": 10, "week": 43, "changes": 10122 }, { "year": 2014, "month": 10, "week": 44, "changes": 1461 }, { "year": 2015, "month": 10, "week": 41, "changes": 682 }, { "year": 2015, "month": 10, "week": 42, "changes": 0 }, { "year": 2015, "month": 10, "week": 43, "changes": 244 }, { "year": 2015, "month": 10, "week": 44, "changes": 21 }],
groups = { '2013': 'firstYear', '2014': 'secondYear', '2015': 'thirdYear' },
temp = {},
result;
data.forEach(function (a) {
temp[a.week] = temp[a.week] || { week: a.week };
temp[a.week][groups[a.year]] = a.changes;
});
result = Object.keys(temp).map(function (k) { return temp[k]; });
document.write('<pre>' + JSON.stringify(result, 0, 4) + '</pre>');

Instead of debugging your code I think a more "algorithmic" approach would be better. Consider this :
function processWeek(week) {
var weekItem = { week: week };
data.forEach(function(item) {
if (item.week == week) switch (item.year) {
case firstYear : weekItem.firstYear = item.changes; break;
case secondYear : weekItem.secondYear = item.changes; break;
case thildYear : weekItem.thildYear = item.changes; break;
default : alert('this will never happen'); break;
}
})
return weekItem;
}
for (var week=41;week<45;week++) {
sampleData.push(processWeek(week));
}
The above produces the desired result -> http://jsfiddle.net/by22q6h8/
The idea is to narrow down the construct of new items to simple steps :
create the item
isolate weeks we are after
determine which changes go to which new attribute.

I'm parsing a json from a website and trying to get some data from it. However, it is giving me undefined values when iterating through a collection of objects. If it's a badly formatted json, unfortunately, I can't change it.
[
{
"startYear": 2014,
"startMonth": 6,
"startDay": 31,
"endYear": 2014,
"endMonth": 7,
"endDay": 29,
"selectedDate": "2014_7_8",
"departureStation": "Manila",
"arrivalStation": "Boracay (Caticlan)",
"departureStationCode": "(MNL)",
"arrivalStationCode": "(MPH)",
"departureLabel": "DEPARTURE",
"arrivalLabel": "RETURN",
"dateMarketHash": {
"date_0_2014_6_31": {
"containerId": "date_0_2014_6_31",
"fromLabel": "From",
"currency": "PHP",
"price": null,
"formattedDate": "Thu, Jul 31, 2014",
"year": "2014",
"month": "6",
"day": "31",
"points": null,
"pointsSuffix": "",
"pointsLabelAppend": ""
},
"date_0_2014_7_1": {
"containerId": "date_0_2014_7_1",
"fromLabel": "From",
"currency": "PHP",
"price": 1929,
"formattedDate": "Fri, Aug 01, 2014",
"year": "2014",
"month": "7",
"day": "1",
"points": 0,
"pointsSuffix": "",
"pointsLabelAppend": ""
}
}
},
{
"startYear": 2014,
"startMonth": 7,
"startDay": 24,
"endYear": 2014,
"endMonth": 8,
"endDay": 23,
"selectedDate": "2014_8_8",
"departureStation": "Boracay (Caticlan)",
"arrivalStation": "Manila",
"departureStationCode": "(MPH)",
"arrivalStationCode": "(MNL)",
"departureLabel": "DEPARTURE",
"arrivalLabel": "RETURN",
"dateMarketHash": {
"date_1_2014_7_24": {
"containerId": "date_1_2014_7_24",
"fromLabel": "From",
"currency": "PHP",
"price": 3079,
"formattedDate": "Sun, Aug 24, 2014",
"year": "2014",
"month": "7",
"day": "24",
"points": 0,
"pointsSuffix": "",
"pointsLabelAppend": ""
},
"date_1_2014_7_25": {
"containerId": "date_1_2014_7_25",
"fromLabel": "From",
"currency": "PHP",
"price": 3079,
"formattedDate": "Mon, Aug 25, 2014",
"year": "2014",
"month": "7",
"day": "25",
"points": 0,
"pointsSuffix": "",
"pointsLabelAppend": ""
}
}
}
]
my code:
// Printing the value of 'day' from each 'dateMarketHash'
for (i = 0; i<json.length; i++)
{
var current = json[i].dateMarketHash;
for(var key in current){
if (current.hasOwnProperty(key)) {
document.write(current.key.day); // Cannot read property 'day' of undefined
}
}
}

No, it is the fact that you are reading "key" and not the variable. You need to use bracket notation, not dot notation.
document.write(current[key].day);
And you should not be using document.write.