Questions about Mathematica's date and time functions.

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7
votes
1answer
159 views

Determining FinancialData for Countries

How do I determine the FinancialData for Australia. For instance the one for USA follows as: FinancialData["NYSE", "Members"] ...
7
votes
3answers
370 views

Find all the last weekends in a year

In order to obtain the weekends of a year you'd use something like this: ...
7
votes
2answers
152 views

DatePlus and DateList are inconsistent with numerical handling of the final element

If you run this code you will see that DatePlus and DateList are inconsistent in the format of the lowest order element of the ...
6
votes
6answers
776 views

Sort list by day names (Monday, Tuesday, etc)

I have some dates in a list, and I want to plot how many of those dates are Monday, Tuesday, etc. I'm using this: data = {...} Tally[DayOfWeek /@ data] and I ...
6
votes
4answers
305 views

How to combine Date and Time objects into DateTime object?

Considering a DateObject d and TimeObject t: ...
6
votes
2answers
719 views

Finding the intersection of two date lists

I've got two lists that look like this ...
6
votes
3answers
370 views

Importing and manipulating strings - time data

I have a list of time durations, which are strings of the form: "hh:mm:ss". Here's a sample for you to play with: ...
6
votes
2answers
250 views

DateList Segmentation of data

I've been trying to separate large segments of DateList formatted data (years worth at a time) into individual days using the Split function. The data has the form: ...
6
votes
4answers
452 views

How to Merge Date and Time?

Given the following time series data where row is date and column is time intervals. ...
6
votes
3answers
284 views

Determining the dates of days

I'm trying to use WeatherData[] to give me (not sure how) the temperature, humidity, wind-speed, cloud cover... at a certain location. I only want the information ...
6
votes
3answers
156 views

EasterSunday replacement in Mathematica 10

The Calendar package, now obsolete, had functionality for "special dates", in particular EasterSunday[]. The documentation says it's been subsumed into Wolfram ...
6
votes
2answers
149 views

How to speed up Min of DateObjects?

I'm in version 10.0.1 using a Dataset to do some plots and things. For one of the plots I need to get the minimum date of a some filtered set of the ...
6
votes
1answer
278 views

Can I automatically stop operation that is too slow?

I need to write code like this: Do operation 1, but if it takes more that 5 seconds then stop it and do operation 2. Is it possible to do this somehow without manual interruption?
6
votes
5answers
418 views

Handling holidays in financial time series

I have two lists: list1and list2, which are financial time series with only 2 variables—date and price. The problem is: these ...
6
votes
1answer
157 views

How to make several DateListPlot have the same scale?

I want to plot some weather data series. Unfortunately the series were collected in different episodes, from which some overlap. I would like to plot them as different plots in a column, but with ...
6
votes
1answer
725 views

Simple countdown timer in Mathematica

I dug around a bit and did not find a simple and clear implementation of countdown stopwatch in Mathematica. I am looking for a function that takes as an input a certain integer and then counts down ...
6
votes
2answers
99 views

Speed up AbsoluteTime with string input

I have millions of strings representing dates in the form: "05-Mar-2004 10:15:00". I would like to convert these to absolute times. For example: ...
6
votes
2answers
147 views

Plot time along the y-axis?

How can I plot times along the Y-axis, (with dates along the X-axis) e.g. ...
6
votes
4answers
700 views

Change string date/time to be understandable for mathematica

I'm trying to convert a string of a data and time to be understandable for mathematica (I want to make time related plots). However, I can get my head around how to do this. For example: ...
6
votes
1answer
327 views

Wait / sleep miliseconds

Is there any way to make Mathematica stop for some miliseconds? I know about the Pause[] but it seems it only works with seconds.
6
votes
2answers
874 views

Select elements of list within a date range

I have a list which consists of elements each of which has a date in DateList format, a number and a flag (Y/N). e.g. ...
6
votes
1answer
135 views

DateList does not output the correct time, but Date does

Bug fixed in 10.0.0+2014080602 I noticed a strange thing when trying the new astronomical data functions in Mathematica 10 on my Raspberry Pi. The Sunrise and ...
6
votes
1answer
132 views
6
votes
1answer
218 views

Throttle EventHandler KeyReleased

What might be the most elegant way to throttle the a,s functions triggered by an ...
5
votes
4answers
214 views

DateListPlot: Highs and Lows

I have this data: ...
5
votes
2answers
258 views

Time Zone Conversion

I use Mathematica to administer my share depots. The depots contain shares of many different time zones. I update the depot values several times a day. My problem is that Sidney, Australia, (it might ...
5
votes
3answers
276 views

Converting between AbsoluteTime and Unix time

By trial and error, I've found that the following gives the current Unix time: AbsoluteTime[] - UPOCH where UPOCH can be defined in any of the following ways: ...
5
votes
2answers
563 views

From a list of dates, get a list of the last date available in each month

I wondered if anyone has another or even a more direct way of finding the last dates of each month available from a list of successive dates? I currently do the following (note: nothing special about ...
5
votes
2answers
157 views

How can AbsoluteTimes be split by date faster?

I have data where the date is stored as an AbsoluteTime. Here's a dummy dataset: ...
5
votes
2answers
99 views

How can DateObject handle calender weeks

I have dates given for a TimeLinePlot. These dates are in {year,week} format. DateObject ...
5
votes
3answers
182 views

DateList's aggressive interpretation of TimeML duration codes

DateList "aggressively" interprets strings, such as "p72h": DateList["p72h"] gives ...
5
votes
3answers
89 views

How to ignore year in DateListPlot

I just upgraded to Mathematica 10, and I am trying to get the hang of the new TimeSeries data objects, which are preventing my old strategy of overlaying data from ...
5
votes
1answer
127 views

Why DateDifference returns machine number?

Is there any specific reason why DateDifference cannot give an exact number in this case? ...
5
votes
4answers
167 views

Getting AbsoluteTiming to display in hours, minutes, and seconds

I'm doing some extended length calculations and was wondering how I could get AbsoluteTiming to display in hours, minutes, and seconds. I googled and found nothing, ...
5
votes
2answers
149 views

How to convert date string with fractional seconds to DateObject

I have a date/time string from a data file in the form "2014/01/09 07:24:36:001". I would like to convert it to a DateObject. I ...
5
votes
1answer
112 views

Handy dates conversion

I feel like something very basic is missing me, $dateformat = {"Year", "Month", "Day", "Hour"}; date = DateString[$dateformat] DateString["Date"] ...
5
votes
1answer
191 views

Problems with TimelinePlot

I'm trying to play with the example in this recent blog post, but I'm having a few basic issues with TimelinePlot: Labels are getting cut off: How can I get ...
5
votes
1answer
45 views

How to modify wrong time zone in a Date object?

How can one modify the wrong time zone in a DateObject, without a conversion? Can one manipulate the TimeZone directly without having the numerical value of the time changing?
5
votes
2answers
172 views

Is it safe to change the value of $TimeZone?

I'd like to configure some of my notebooks to assume all calculations using dates, times and locations (notably AstronomicalData , but others too) take place at the ...
5
votes
1answer
84 views

“ComputedDate”'s interpretation of “next”

Today Interpreter["ComputedDate"] /@ {"next Monday", "next Tuesday", "next Wednesday"} What explains this behavior? Can ...
5
votes
1answer
108 views

DatePlus changes in V10.2, can I return to previous behaviour?

Now in V10.2, DatePlus has changed it behaviour in a undocumented way. Now, DatePlus[n] (with n as ...
5
votes
1answer
66 views

DateObject for current date skips a day when crossing the date line with TimeZone

The DateObject was introduced in version 10 of Mathematica. One can call it to fetch the current local date and time: ...
5
votes
1answer
121 views

How to remove the TimeZone from a TimeObject

TimeObject constructor adds TimeZone even when it's not meaningful or appropriate. In this example, Mathematica imputes ...
5
votes
1answer
107 views

ChineseLunar calendar system mystery

I tried to make a custom holiday calendar for the Korean Stock Exchange. And I found that the built-in "ChineseLunar" calendar system gives me an awkward result. The code is ...
4
votes
4answers
405 views

How to convert Dates with format 2016/03/1 to become {2016,3,1}

I have a problem to convert tide data with the form as follows. 2016/03/23,08:00,0.89,* 2016/03/23,09:00,1.41,* 2016/03/23,10:00,1.67,* 2016/03/23,11:00,1.44,* 2016/03/23,12:00,0.82,* ...
4
votes
4answers
240 views

Extract Specific Dates from DateList

Hopefully this is an easy question but I couldn't find an easy answer anyway. Surely there is some simple way to splice this... I want to take a large datelist in the format of {{2014,12,31}, value} ...
4
votes
2answers
2k views

No weekends please

I need to get the DateValues of the last 30 days (starting from yesterday, not today!) excluding saturdays and sundays. I want that the dates are german time (GMT ...
4
votes
4answers
279 views

Finding the location of the last day of the month in a list of dates

My question differs from earlier questions about getting the eom dates from a list; I want to get the position of those dates so I can get the corresponding values from other lists. My problem seems ...
4
votes
1answer
154 views

Poor (network) performance of Interpreter[“Time”]

I was surprised to see that Interpreter requires external WR resources as this is not documented, at least not here. On a 3Ghz iMac, took ~half a minute to ...
4
votes
2answers
83 views

How to override DisplayForm of (mixed) time Quantity

What's the best approach to overriding DisplayForm for specific types of Quantity eg time especially w/ mixed units? Current is ...