# Tagged Questions

Questions about Mathematica's date and time functions.

94 views

### TimelinePlot with Interval in Associations

Bug introduced in 10.2 This is related to a previous question I asked about TimelinePlot and multiple associations (Behavior of TimelinePlot with multiple ...
76 views

### How to extract the time t of an interpolated function created by NDSolve? [duplicate]

I'm working with the function NDSolve. I give it the time of integration, the time I want it to evaluate my differential equations. Sometimes, it crashes before the end of its attribuated time ; For ...
46 views

### How to adjust the FrameTicks length in DateListPlot?

suppose I have the data for DateListPlot: ...
324 views

### How to combine Date and Time objects into DateTime object?

Considering a DateObject d and TimeObject t: ...
191 views

### How to make a cumulative time plot?

So I'm working with this data set where there is just one input(a date and time) per line in a .csv file. I've let Mathematica understand the input using "DateStringFormat". The time looks like Year-...
429 views

### How much time should one give Mathematica for an integral evaluation?

Sometimes when I do integrals in Mathematica (M), it keeps thinking and thinking and I have no idea what is going on inside M. For how long should one wait or how does one know whether M has not got ...
237 views

Bug introduced in 10.1 and fixed in 10.3 TimeLinePlot was introduced in 10.1 I have some data from wikipedia. ...
495 views

### Converting timestamps into a decimal in minutes

I am importing a list of timestamps (hour:minutes:seconds) from a series of text files. I have the list: ...
117 views

### Handy dates conversion

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

### My simulation is not never finishing and it is taking so much time?

I am running simple code which involves calculation of two first order differential equations.It is taking so much time and i am unable to get the results as the simulation is never finishing. ...
386 views

### How could I transform the YYYYDDD date string/Integer to YYYYMMDD date string?

suppose I have lots of YYYYDDD date Integers which look like(for example): ...
214 views

### DateListPlot: Highs and Lows

I have this data: ...
216 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 ...
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: ...
118 views

### How to convert absolute time to local time?

I tried this code: ...
211 views

### SetOptions for CoordinatesToolOptions for DateListPlot?

Bug introduced in 10.0 and persisting through 10.2.0 or later DateListPlot does not respect my Options setting for ...
135 views

### Mean duration between two specific data points

I have dataset such as: ...
72 views

### Why are the labels twitching vertically in TimelinePlot?

Why are labels jumping up and down here: ...
77 views

### Convert Dates to values on an X axis

I have a bunch of dates and values which I put into the DateListPlot to get a graph. However I would also like to put this information into the Fit or LeastSquares to estimate what the value would be ...
190 views

### How to calculate time period?

I have the starting and ending dates and times. And I need to calculate the night time in this period (from 10 pm (22) to 6 am (6)). Example: starting date and time is {2015, 1, 4, 3, 10} ending date ...
94 views

### Improving semantic interpretation of dates

SemanticInterpretation and Interpreter are promising but imperfect, eg extracting dates and calendar expressions from semi-...
250 views

### Behavior of TimelinePlot with multiple datasets of associations

Bug introduced in 10.1 and fixed in 10.3 The following TimelinePlot behaves as I would expect: ...
127 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 ...
113 views

### Make a time IntervalSlider

I want to make a time interval slider with an initial setting of (10:00:00 Mar. 8 2015, 12:30:00 Mar. 8 2015) and which varies from 00:00:00 Mar. 8 2015 to 22:30:00 Mar. 8 2015 with a granularity of ...
2k views

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 +...
139 views

### How to restart a Clock

The code below is to demonstrate color afterimages. The user chooses a color, fixates the changing number at the center until it reach 30 (seconds), then manually switches to white to observer the ...
68 views

### DateValue returns inconsistent types

More of a 'why' than a 'how' question... DateValue[{2014,4,12},"DayName"] returns Saturday, a symbol rather than the string "Saturday". Every other result that ...
56 views

### DateObject from AbsoluteTime broken

In the middle of a session (10.0.2 / Win64 / 2.7Gb working set - peak was over 7Gb) the form/definition for DateObject from an integer has disappeared. ...
94 views

### DatePlus and DayPlus perform much worse than my user-defined-function

I was debugging a function speed, and discovered that the time bottleneck was in DatePlus. I tried to change to DayPlus and get ...
52 views

### How to change time zone for all outputs? [closed]

How to change the time zone in Mathematica for all functions returning a date or time?
52 views

### Change date format in nested lists

I have a list of index symbols and data as follows: ...
209 views

### Delete rows based on specific periods

I have data (.xlsx format): two columns - data in first column imported as DateObject (dates with specific time), data in second column are numbers (113388.28, 865165.98 etc.). I want to delete the "...
291 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: <...
149 views

### AbsoluteTime parse two different date formats

I have a series of dates that regularly change format (24 hrs/12 hrs). Is there an easy way to parse this data? ...
264 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 ...
200 views

### NDSolve: basic settings for PDEs

I am trying to learn how to solve PDEs in Mathematica in order to deal with relatively simple problems without needing to formulate weak formulations in FreeFem++, which is rather time consuming for ...
178 views

### How to plot multiple yearly data in one graph

There is a dataset: for each year a single data for 6 seas. I would like to have a graph to visualize paralel changes. This is what I attempted to reproduce http://www.eea.europa.eu/data-and-maps/...
64 views

### Is Daylight Savings Time accounted for when using AbsoluteTime[]? [closed]

I have been running rather long computations lately and timing them using AbsoluteTime[] by calling it at the start and end of the computation. ...
286 views

### Min, Max are slow on TimeObjects

fixed in 10.1 (windows) There's something wrong with how Min and Max are implemented for ...
38 views

### Expose TimeObject fractions of a second and user-defined formatting

The default TimeObject formats (doc page), don't display fractions of seconds: ...
159 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 ...
80 views

### How to convert a string representing date into a DateList expression?

How to convert a string representing date into a DateList expression? For example, how to turn "1/2/2000" into {2000,1,2} assuming American style, and {2000, 2, 1} assuming European style, ...
138 views

### Is it possible to specify GMT as default in OpenSQLConnection or JDBC?

I'm connecting to a PostgreSQL database, with tables containing TIMESTAMPs with timezone, using ...
71 views

### How can I set up a cell style that is ascending dates? [closed]

Outline style notebooks have cell counters that are simply ascending numbers, but what if I want to apply a function to them and have descending dates like this: So that they auto format and the ...
277 views

### How do I remove the quotation marks from each element of a list containing dates that I have import from excel?

I've been stuck in this problem for 1 week. I just want to make a graph (Log-Return vs time (in year, month, day)). The code is: ...
160 views

### Get the complement date range

Suppose that I have a date range list drlist = {{"2015-01-01", "2015-01-05"}, {"2015-01-07", "2015-01-07"}, {"2015-01-12", "2015-01-23"}} ...
79 views

### Why does TimeSeriesShift is just adding a fixed number of days?

I'd like to shift all contents of a TimeSeries object by one month. By shifting Feb. 1st I would expect to receive Mar. 1st. However it's not the case for Mathematica: ...
244 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} ...
184 views

### Trace two DateListPlots?

I currently have two DateListPlots in the same graph, with two different y-axes. I downloaded the package "TwoAxisDateListPlot" to accomplish this with ease. Now I want to be able to trace both of the ...
167 views

### Plotting CSV files with UTC Universal Time

So I have many CSV files in format like this: 2014-12-11T16:13:13.038337Z , 3.90092 2014-12-11T16:14:13.456558Z , 3.89734 2014-12-11T16:15:12.444318Z , 3.90092 I imported a CSV file ...