How to calculate number of hours after night start

Question

I have current hour and I want to count how many hours have passed since the start of the night. For example night started at 19:00 and current hour is 4:00, how can I calculate this (especially it must work in both cases e.g. 23:00 and 4:00)? I only have this:

now = new Date(),
now = now.getHours();
night_start = 19;

http://stackoverflow.com/questions/4944750/how-to-subtract-date-time-in-javascript — Pieter21, Aug 02 '14 at 14:09
`var diff = night_start >= now ? ((24-night_start) + now) : now - night_start` — adeneo, Aug 02 '14 at 14:16

score 0 · Accepted Answer · answered Aug 02 '14 at 14:15

0

You can doit like this

now = new Date(),
now = now.getHours();
night_start = 19;

var hours = ((now - night_start)<0?24:0)+( (now - night_start));

answered Aug 02 '14 at 14:15

Khalid

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How to calculate number of hours after night start

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