Questions about Mathematica's date and time functions.

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1
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1answer
67 views

DayRound Rounding Values:No difference between “Preceding” and “Following”?

On Mathematica 10.0.1 both DayRound[{1980, 2, 29}, "EndOfMonth", "Preceding"] and ...
4
votes
2answers
133 views

How to sum values in the list that belongs to same week

I need to sum values that belongs to same week. For example, I have the list x with one column and n rows. Format: ...
5
votes
1answer
86 views

“ComputedDate”'s interpretation of “next”

Today Interpreter["ComputedDate"] /@ {"next Monday", "next Tuesday", "next Wednesday"} What explains this behavior? Can ...
1
vote
0answers
120 views

How to create a complex variable from dated list values

Can anyone help me to construct a variable "PI" from values of variable x. Variable x represents a group of two time series rj and ri on equal dates(joined two dated lists with states).Variable x have ...
6
votes
2answers
151 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 ...
2
votes
1answer
179 views

A possible bug with regard to DateObjects in Version 10?

Bug introduced in 10.0 and fixed in 10.1 Bug related to the Suggestion Bar Bug While getting used to the new data type Date Object in Version 10 I noted that ...
1
vote
2answers
134 views

How to select states with equal times

Can anyone show me how to select the states that have equal times-dates. For example, i have two time series. First that have 10 observations, say from 2014/10/1 to 2014/10/10, and second that have 7 ...
6
votes
4answers
733 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: ...
2
votes
1answer
276 views

DateListPlot with multiple data sets and incongruous timelines?

I am using Mathematica to analyze some sales data for my company. (A copy of the available data is here.) We are trying to analyze the sales trends for each month by item. DateListPlot works well ...
6
votes
1answer
159 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 ...
9
votes
5answers
506 views

Calendar view outline

How to compute the outline of a calendar month like this D3 example. (D3 is a functional language built on JavaScript developed at Stanford and used by New York Times to deploy interactive graphics.)...
6
votes
1answer
229 views

Throttle EventHandler KeyReleased

What might be the most elegant way to throttle the a,s functions triggered by an EventHandler...
0
votes
1answer
190 views

How to get an Excel-like surface plot with ListContourPlot3D

I'm trying to create an Excel like surface plot from an import of data from an Excel workbook. I get the data without issue. It is a set of percentages in bin ranges over a series of dates. I'd ...
1
vote
0answers
67 views

Make a table of changes in US coinage

I thought of an innovative use of Mathematica/Alpha that I think Stephen Wolfram would really love, but I can't figure out how to get it to work. The idea is to make a table that would chart the ...
9
votes
2answers
392 views

interpolating function over dates

I've got a bunch of readings at various dates and times. I'd like to be able to interpolate and then integrate over, say days. I can do this by converting my date/time to ...
8
votes
3answers
372 views

Timeline plotting: horizontal bars of time intervals

This text file logs the time that a process (identified by a number) changes state ("Brown", "Blue" etc.") ...
2
votes
1answer
148 views

Correct handling of milliseconds in a date time string

DateString[{2014, 5, 7, 13, 47, 44.760}, {"Year", "-", "Month", "-", "Day", " ", "Hour", ":", "Minute", ":", "Second", ".", "Millisecond"}] Returns 2014-05-...
8
votes
5answers
233 views

How to do DateDifference on table items containing dates

I have a Table with data in form {{date}, value}: ...
7
votes
3answers
229 views

Different results with DateRange and LeapYearsQ in Mathematica 9 and 10

With Mathematica 9.0 for Mac OS X x86 (64-bit) (January 24, 2013) one could use DateRange[{2000}, {2010}, "Year"] to achive ...
6
votes
1answer
135 views
8
votes
1answer
202 views

Bug in DateListPlot in Mathematica 10

Mentioned this already in an answer to a related question. DateListPlot in Mathematica 10 has a horrible bug: If two points have the same time coordinate, only one is plotted; the others are ignored. ...
9
votes
3answers
495 views

Does Mathematica have Month Range and Day range?

It is known that CharacterRange["a", "z"] gives list of characters from a to z. Does Mathematica have something similar for weekdays and months of the year? ...
1
vote
0answers
40 views

Updating values in a Dataset [duplicate]

I'm starting to work with datasets. They seem like a useful addition to Mathematica. However, there's one fairly major stumbling block I can't get over. How do I update data in a dataset? I have a ...
3
votes
0answers
175 views

Memory problem in Mathematica 10

I'm having a problem with memory. I'm doing nonliner fits of several data lists to a system of differential equations. When I evaluate the "Do" cycle the memory grows with the iteration step up to my ...
4
votes
3answers
183 views

How to get a list of days from July 4th to Oct 4th over a range of years

I'd like to create a list with days from the 4th of July to the 4th of October starting in July 1970 to the current date. I tried to use DateRange, but I'm a bit ...
0
votes
1answer
98 views

Export date with specified format

My problem is that I want use PGFplot in $\LaTeX$ to draw my graphs, which x axis is a date. Therefore the output file has to have one column "UTC time" (YYYY-MM-DD hh:mm:ss) and the second one is the ...
1
vote
2answers
62 views

TimeConstrained for Table?

Let's say that I have a function f[i] that takes quite a while to evaluate (evaluation time is different for different i) and I'd like to have as many values of <...
3
votes
2answers
128 views

Slow work of TimeSeriesWindow

I have financial data (list of time-values pairs). There are more than 13000 elements. ...
4
votes
1answer
159 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 ...
-1
votes
1answer
163 views

Plot CPU time vs iteration? [duplicate]

I would like to generate a plot of CPU time vs number of iterations. For example, if I were to calculate the solution of a system of differential equations in state-space form using the summation of e^...
4
votes
1answer
373 views

BarChart that lines up with dates in DateListPlot

I am trying to create a chart similar to the view offered by TradingChart, but with custom data not relating to finance. ...
7
votes
3answers
502 views

Friday the 13th related tables

This code ...
6
votes
1answer
286 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?
1
vote
2answers
231 views

Extract data from DateListPlot, limited by PlotRange

Extracting the points from a line in a ListPlot in this answer uses points = Cases[Normal@plot, Line[pts_] :> pts, Infinity]; This works in DateListPlot (...
3
votes
3answers
84 views

Alternatives to DateQ of Calendar Package

This answer notes that Calendar package has a function DateQ but the documentation suggests that the input is limited to a fixed ...
-6
votes
1answer
97 views

how to mean of day,month value

data={{{2006, 1, 1, 0, 0, 0.}, 326.492, {2006, 1, 1, 3, 0, 0.}, 323.08, {2006, 1, 1, 6, 0, 0.}, 314.223, {2006, 1, 1, 9, 0, 0.}, 314.361, {2006, 1, 1, 12, 0, 0.}, 322.048, {2006, 1, 1, 15, 0, ...
0
votes
1answer
99 views

Text with date, how to convert?

I use this script to recognise a date in a textfile and write the result in another file. ...
0
votes
2answers
149 views

How to partition three years of data into daily samples

I'm trying to find mean of temperature data list. The temperature data list has 3 hours steps which means I have 365*8=2920 temperature measurements per year. My data are temperatures of 13 years. ...
6
votes
1answer
136 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 <...
0
votes
2answers
321 views

Convert epoch seconds to date [duplicate]

I have got the following datetime from an API: 1395401384298 I am guessing it is in epoch miliseconds time (it should be one day in 2014) How can i convert it into a more readable String? I have been ...
2
votes
0answers
528 views

Speeding up Nonlinearmodelfit by constraining parameters?

I have a complicated parametric PDE that can be fitted to some data with NonlinearModelFit, but takes several hours to estimate the best values of the four free parameters. Currently, the code ...
2
votes
2answers
157 views

Counting Events in a moving date range

I want to count the number of times events take place in a date range. The counting is done over a window of e.g. 28 days where the goal is to have between 11 and 13 events in the time window. The ...
6
votes
1answer
336 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.
2
votes
2answers
187 views

I'm trying to filter a date range by day of month and day of week - what am I doing wrong?

I am trying to generate a list of dates that match two criteria: they have to all be the first of the month, and they have to be a particular day of the week, Sunday in my case. The code I have ...
1
vote
1answer
254 views

Splitting dates into groups in half year steps

list = DayRange[{1999, 1, 1}, {2014, 2, 6}] I want to split this list into sublists one and a half year long, moving a half year forward every time. That would ...
4
votes
4answers
282 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 ...
6
votes
4answers
453 views

How to Merge Date and Time?

Given the following time series data where row is date and column is time intervals. ...
1
vote
1answer
62 views

How to get the time when a notebook is saved and closed

I want to get the time when a notebook is created and the time when the notebook is saved and closed, that is to say, the whole time when a notebook exist. What should I do? Thank you!
13
votes
2answers
377 views

ScheduledTask with scoped variables. Working with timed evaluation

I guess I have to try harder and focus more but timed evaluation always frustrates me. I will show the issue on simple example of delayed trigger. ...