How to interpret Timelien for HighStock - json

I am using the HighStock API of HighChart.
The demo:
http://jsfiddle.net/gh/get/jquery/1.9.1/highslide-software/highcharts.com/tree/master/samples/stock/demo/compare/
Makes a timeline on the x-Axis.
But the data JSON data for the graph has the following keys:
E.g. for AAPL:
?(/* AAPL historical OHLC data from the Google Finance API */
[
/* Dec 2008 */
[1229472000000,12.74],
[1229558400000,12.78],
[1229644800000,12.86],
[1229904000000,12.25],
[1229990400000,12.34],
[1230076800000,12.15],
[1230249600000,12.26],
[1230508800000,12.37],
[1230595200000,12.33],
[1230681600000,12.19],
How do all the 1229.... values relate to Date/Time?? I mean how does
1232582400000
relate to 22. January 2009???
And I have data int he following format in Java:
2015-12-10 15:27
How should I use them in the HighChart API?

The numeric time stamps you see as "1232582400000" is the javascript time stamp. I believe it is UNIX epoch time in milliseconds (multiply epoch time by 1000). You can convert your human-readable time values into javascript time in any number of ways. The basic example if you have year, month, day, hour, and second would be to make your data series use Date.UTC():
[Date.UTC(year, month, day, hour, minute), yValue]
"Unix time (also known as POSIX time or Epoch time) is a system for
describing instants in time, defined as the number of seconds that
have elapsed since 00:00:00 Coordinated Universal Time (UTC),
Thursday, 1 January 1970, not counting leap seconds."
(source)

Related

Date validation with the clock command

Consider the following code run on a Windows 7 system:
% info patchlevel
8.6.4
% clock scan "1995-01-35" -format "%Y-%m-%d"
791856000
% clock format [clock scan "1995-01-35" -format "%Y-%m-%d"] -format "%Y-%m-%d"
1995-02-04
%
I ran into this situation when trying to determine if a string was a valid date, I was expecting the first clock scan to fail as 35 isn't a valid day, but what happens is that I get a date 35 days after the 1st of January.
In my code I'm now comparing the output of the 2nd clock command to the original input and deciding that the string isn't really a valid date if the result is different.
Is there a better way to validate a date and is this the expected behaviour of the clock command, I can't find it described in the manual page for clock?
It is not in-built functionality in Tcl. If the dates/months are exceeding, then it is added to the successive days/months.
In your case, you are giving 35th of month January. The additional 4 days (i.e. 31 + 4 = 35) are added and calculated as month February's 4th day.
In the bizarre case that adding the given number of days yields a date
that does not exist because it falls within the dropped days of the
Julian-to-Gregorian conversion, the date is converted as if it was on
the Julian calendar.
Adding a number of months, or a number of years, is similar; it
converts the given time to a calendar date and time of day. It then
adds the requisite number of months or years, and reconverts the
resulting date and time of day to an absolute time.
If the resulting date is impossible because the month has too few days
(for example, when adding 1 month to 31 January), the last day of the
month is substituted. Thus, adding 1 month to 31 January will result
in 28 February in a common year or 29 February in a leap year.
proc is_valid_date {date {date_format "%Y-%m-%d"}} {
return [string equal [clock format [clock scan $date -format $date_format] -format $date_format] $date]
}
The date format is an optional and defaulted to %Y-%m-%d. If the format is not matching then it will fail. You can handle the exceptions.
Output :
% is_valid_date "1995-02-28"
1
% is_valid_date "1995-01-35"
0
%
We are converting the date to a long and reverting to the date again. If both are not same, then the given input is incorrect.
Reference : clock

calculating YearWeek from Tcl

I'm trying to correctly calculate working Year/Week number from a date field.
I tried to use the clock format command as follows
% clock format [clock scan "2016.01.01" -format "%Y.%m.%d"] -format "%Y-WW%V"
2016-WW53
and while the Week number is correct, the year is not because in this case Jan1 lands in week 53, as it did in 2016. Since the Tcl clock format command specifies the week number and the year separately, I end up with Jan 1, 2016 being shown as 2016-WW53 but this should be shown as 2015-WW53.
Is there a built in function for this or do I need to use an if/then condition to choose the year correctly?
Just use the modifier %G:
clock format [clock scan "2016.01.01" -format "%Y.%m.%d"] -format "%G-WW%V"
Output:
2015-WW53
From the manual:
%G
On output, produces a four-digit year number suitable for use with the week-based ISO8601 calendar; that is, the year number corresponds to the week number produced by %V. On input, accepts such a four-digit year number, possibly with leading whitespace.

Does the Google Directions API use UTC or Local Time?

I am developing a transit navigation app using the Google Directions API.
The API requires me to submit a departure time (departure_time) for transit queries.
Is it necessary to convert the local time to UTC time for this parameter?
I could not validate it through the API's response, as there is no accurate time returned in it.
That Doc Was In Error
Apparently the Google team writing that doc page made an error and later fixed it.
The number you report 1343605500 is no longer found on that page. Today the number on that page is 1343641500. I suspect you did indeed see that number on that page previously. Googling (ironically enough) for site:https://developers.google.com 1343605500 does list that page as a hit. Apparently the hit is based on a cached copy of the old erroneous page. Even Google cannot escape the reach of Google.
Work in UTC/GMT
Is it necessary to convert the local time to UTC time for this parameter?
Yes.
The API works with GMT/UTC (no time zone offset), which only makes sense when you think about it. Almost always, the best practice for handling date-time is to perform your business logic, serialization, database records, and so on in UTC, then convert to local time only for presentation to the user.
Just looking at the example URL itself suggests it is in UTC. The only possible reference to a local time zone would be the word "Brooklyn" which is certainly not a clear unique identifier for a time zone.
http://maps.googleapis.com/maps/api/directions/json?origin=Brooklyn&destination=Queens&sensor=false&departure_time=1343641500&mode=transit
And of course the doc says the API uses UTC/GMT:
the desired time of departure as seconds since midnight, January 1, 1970 UTC
Poor Writing
The confusion stems from the poor writing in that documentation page. They need to append a crucial "UTC" or "GMT" to that "9:45 am". Mentioning New York and 9:45 in the same breath implies local time, whereas that example is truly 5:45 in the morning local time in Brooklyn.
The below request searches for Transit Directions from Brooklyn, New York to Queens, New York. When requesting transit directions, be sure to specify either a departure_time or arrival_time.
Note that in this example the departure time is specified as July 30, 2012 at 09:45 am. Update the parameter to a point in the future before submitting the request.
Old Versus New Numbers
Old number: 1343605500 (reported in the answer by davidg, and by googling)
New number: 1343641500 (found 2013-12)
Number if they had actually meant 9:45 in New York: 1343655900.
Example Code
I don't do JavaScript. So instead, I present some Java code using the sophisticated Joda-Time 2.3 date-time handling library running in Java 7. I use both the old (erroneous) and new (correct) numbers to show the date-time in both UTC and New York time zones. Furthermore, I calculate the number of seconds since epoch would have been used to get to 9:45 am July 30 2012 in New York, to produce a third number of seconds.
The Google API uses seconds, while Joda-Time uses milliseconds, so I multiply or divide by a thousand.
// © 2013 Basil Bourque. This source code may be used freely forever by anyone taking full responsibility for doing so.
// import org.joda.time.*;
DateTimeZone timeZone_NewYork = DateTimeZone.forID( "America/New_York" );
// On this page:
// https://developers.google.com/maps/documentation/directions/#ExampleRequests
// …look for the following two paragraphs…
// --
// The below request searches for Transit Directions from Brooklyn, New York to Queens, New York. When requesting transit directions, be sure to specify either a departure_time or arrival_time.
// Note that in this example the departure time is specified as July 30, 2012 at 09:45 am. Update the parameter to a point in the future before submitting the request.
// --
// Below that text, find this URL:
// http://maps.googleapis.com/maps/api/directions/json?origin=Brooklyn&destination=Queens&sensor=false&departure_time=1343641500&mode=transit
// Extract that departure time of 1,343,641,500 seconds since the Unix Epoch of beginning of 1970 UTC.
// Apparently in the past that page erroneously used the number 1343605500 where today it uses 1343641500.
// Use the correct number found on that page today, 2013-12-25: 1343641500.
DateTime dateTimeInUtcWithNewNumber = new DateTime ( ( 1343641500L * 1000L ), DateTimeZone.UTC );
DateTime dateTimeInNewYorkWithNewNumber = dateTimeInUtcWithNewNumber.toDateTime( timeZone_NewYork );
System.out.println( "dateTimeInUtcWithNewNumber: " + dateTimeInUtcWithNewNumber );
System.out.println( "dateTimeInNewYorkWithNewNumber: " + dateTimeInNewYorkWithNewNumber );
// Use the old erroneous number previously found on that page: 1343605500.
DateTime dateTimeInUtcWithOldNumber = new DateTime ( ( 1343605500L * 1000L ), DateTimeZone.UTC );
DateTime dateTimeInNewYorkWithOldNumber = dateTimeInUtcWithOldNumber.toDateTime( timeZone_NewYork );
System.out.println( "dateTimeInUtcWithOldNumber: " + dateTimeInUtcWithOldNumber );
System.out.println( "dateTimeInNewYorkWithOldNumber: " + dateTimeInNewYorkWithOldNumber );
// Calculating the number that should have been used if the Google team had actually meant 9:45 AM local time in New York: 1343655900.
DateTime dateTimeInNewYork_2012_07_30_09_45 = new DateTime ( 2012, 7, 30, 9, 45, 0, timeZone_NewYork );
System.out.println( "dateTimeInNewYork_2012_07_30_09_45: " + dateTimeInNewYork_2012_07_30_09_45 );
System.out.println( "dateTimeInNewYork_2012_07_30_09_45 in seconds since Unix epoch: " + ( dateTimeInNewYork_2012_07_30_09_45.getMillis() / 1000L ) );
When run…
dateTimeInUtcWithNewNumber: 2012-07-30T09:45:00.000Z
dateTimeInNewYorkWithNewNumber: 2012-07-30T05:45:00.000-04:00
dateTimeInUtcWithOldNumber: 2012-07-29T23:45:00.000Z
dateTimeInNewYorkWithOldNumber: 2012-07-29T19:45:00.000-04:00
dateTimeInNewYork_2012_07_30_09_45: 2012-07-30T09:45:00.000-04:00
dateTimeInNewYork_2012_07_30_09_45 in seconds since Unix epoch: 1343655900

Calculate date of birth from age at specific date [MySQL or Perl]

Apologies if this is a really simple question but I am interested in trying to reach an accurate answer and not just a "rounded" up answer.
My problem is: I know somebody is 27.12 on the 18th of March 2008 (random example). How can I calculate, to the nearest approximation, his date of birth. Age is always provided as a real number to two decimal points.
The solutions through simple fractional calculation are 1981-02-03 and the day before, due to rounding. As eumiro said, the resolution of 1/100 year is not precise enough, so it might still be off a day or two with the real date.
use DateTime qw();
use POSIX qw(modf);
my $date = DateTime->new(year => 2008, month => 3, day => 18); # 2008-03-18
my $age = 27.12; # 27.12
my ($days, $years) = modf $age; # (0.12, 27)
$days *= 365.25; # 43.83
# approx. number of days in a year, is accurate enough for this purpose
$date->clone->subtract(years => $years, days => $days); # 1981-02-03
$date->clone->subtract(years => $years, days => 1 + $days); # 1981-02-02
eumiro's answer does the trick; the following, using the Time::Piece module (bundled with Perl since 5.10) is perhaps more maintainable.
use strict;
use warnings;
use 5.010;
use Time::Piece;
use Time::Seconds;
my ($date, $age) = ('2008-03-18', 27.12);
my $birthday = Time::Piece->strptime($date, '%Y-%m-%d') - $age*ONE_YEAR;
say $birthday->ymd();
This will get you within a few days of the actual birthday, due to the lack of accuracy (1/100 year) in the age.
use strict;
use Time::Local;
my $now = timelocal(0, 0, 12, 18, 3-1, 2008);
my $birthday = $now - 27.12 * 365.25 * 86400;
print scalar localtime $birthday;
returns Mon Feb 2 22:04:48 1981.
Your precision is 0.01 year, which is roughly 3 days, so you even cannot cover all birthdays.
My method does not cover leap years very well, but you cannot really calculate exactly with them. Imagine the 01-March-2008. What date was "1 year and 1 day" before this date? 28-February-2007 or the not existing 29-February-2007?
A method that permits greater accuracy simply takes advantage of existing MySQL Date/Time functions. If working inside the MySQL, you can calculate the age with great precision by converting each of two dates to seconds in the TO_SECONDS() conversion and then manipulating the results to the desired precision. In these cases, the dates are in 'yyyy-mm-dd hh:mm:ss' formats and a year is assumed to have mean length of 365.242 days.
ROUND((TO_SECONDS(AnyDateTime) - TO_SECONDS(DateOfBirth))/(365.242*60*60*24),3) as age,
e.g.:
ROUND((TOSECONDS('2013-01-01 00:00:00') - TO_SECONDS('1942-10-16')/(365.242*60*60*24),3) as AGE --> 70.214
Alternatively you can use the DATEDIFF() conversion which provides the answer in days:
ROUND(DATEDIFF('2013-01-01 00:00:00','1942-10-16')/365.242,3) AS age --> 70.214

Calculate date from numeric value

The number 71867806 represents the present day, with the smallest unit of days.
Sorry guy's, caching owned me, it's actually milliseconds!
How can I
calculate the currente date from it?
(or) convert it into an Unix timestamp?
Solution shouldn't use language depending features.
Thanks!
This depends on:
What unit this number represents (days, seconds, milliseconds, ticks?)
When the starting date was
In general I would discourage you from trying to reinvent the wheel here, since you will have to handle every single exception in regards to dates yourself.
If it's truly an integer number of days, and the number you've given is for today (April 21, 2010, for me as I'm reading this), then the "zero day" (the epoch) was obviously enough 71867806 days ago. I can't quite imagine why somebody would pick that though -- it works out to roughly 196,763 years ago (~194,753 BC, if you prefer). That seems like a strange enough time to pick that I'm going to guess that there's more to this than what you've told us (perhaps more than you know about).
It seems to me the first thing to do is verify that the number does increase by one every 24 hours. If at all possible keep track of the exact time when it does increment.
First, you have only one point, and that's not quite enough. Get the number for "tomorrow" and see if that's 71867806+1. If it is, then you can safely bet that +1 means +1 day. If it's something like tomorrow-today = 24, then odds are +1 means +1 hour, and the logic to display days only shows you the "day" part. If it's something else check to see if it's near (24*60, which would be minutes), (24*60*60, which would be seconds), or (24*60*60*1000, which would be milliseconds).
Once you have an idea of what kind of units you are using, you can estimate how many years ago the "start" date of 0 was. See if that aligns with any of the common calendar systems located at http://en.wikipedia.org/wiki/List_of_calendars. Odds are that the calendar you are using isn't a truly new creation, but a reimplementation of an existing calendar. If it seems very far back, it might be an Julian Date, which has day 0 equivalent to BCE 4713 January 01 12:00:00.0 UT Monday. Julian Dates and Modified Julian dates are often used in astronomy calculations.
The next major goal is to find Jan 1, 1970 00:00:00. If you can find the number that represents that date, then you simply subtract it from this foreign calendar system and convert the remainder from the discovered units to milliseconds. That will give you UNIX time which you can then use with the standard UNIX utilities to convert to a time in any time zone you like.
In the end, you might not be able to be 100% certain that your conversion is exactly the same as the hand implemented system, but if you can test your assumptions about the calendar by plugging in numbers and seeing if they display as you predicted. Use this technique to create a battery of tests which will help you determine how this system handles leap years, etc. Remember, it might not handle them at all!
What time is: 71,867,806 miliseconds from midnight?
There are:
- 86,400,000 ms/day
- 3,600,000 ms/hour
- 60,000 ms/minute
- 1,000 ms/second
Remove and tally these units until you have the time, as follows:
How many days? None because 71,867,806 is less than 86,400,000
How many hours? Maximum times 3,600,000 can be removed is 19 times
71,867,806 - (3,600,000 * 19) = 3,467,806 ms left.
How many minutes? Maximum times 60,000 can be removed is 57 times.
3,467,806 - (60,000 * 57) = 47,806 ms left
How many seconds? Maximum times 1,000 can be removed is 47 times.
47,806 - (1,000 * 47) = 806
So the time is: 19:57:47.806
It is indeed a fairly long time ago if the smallest number is in days. However, assuming you're sure about it I could suggest the following shell command which would be obviously not valid for dates before 1st Jan. 1970:
date -d "#$(echo '(71867806-71853086)*3600*24'|bc)" +%D
or without bc:
date -d "#$(((71867806 - 71853086) * 3600 * 24))" +%D
Sorry again for the messy question, i got the solution now. In js it looks like that:
var dayZero = new Date(new Date().getTime() - 71867806 * 1000);