Questions tagged [date-and-time]
Questions about Mathematica's date and time functions.
530
questions
3
votes
3
answers
27
views
Cases syntax when expression sought is a Quantity
From the following list I wish to extract those cases for which the magnitude of a quantity is greater than zero for which I would like to then create a DateListPlot.
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- 1,734
1
vote
2
answers
64
views
How to format TimeObject with 12-hour AM/PM format?
Interpreter["Time"] does the opposite of what I want, convert a date or time in AM/PM format to 24-hour, but is there any way to display ...
- 341
0
votes
1
answer
72
views
How to take a satellite image in Mathematica at different times?
I want to see the satellite image of the same area at different times. But by entering the following code, also shows the same picture with changing times.
...
- 159
1
vote
1
answer
66
views
7
votes
1
answer
126
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How to adjust PlotHighlighting of version 13.3 to use custom labeling function?
Consider the following dummy data.
...
- 9,043
6
votes
2
answers
227
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Create Datetime and add milliseconds
I want to create a datetime with milliseconds in the form:
"2023.07.22 12:34:56.123";
To which I can add a certain amount of milliseconds (e.g. with the <...
- 2,945
1
vote
1
answer
60
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Interpolation of date-time data to fill in missing data for data sources with different time resolution
I have 2 data sources with different data acquisition rates. My first data source is a temperature measurement over time with a resolution of 1 s. My second source ...
- 490
9
votes
4
answers
602
views
Check if a string is a date
I have a list of strings,
{"BD4675365", "Corp", "Managers", "Syndicate", "2021-03-08", "8434926"}
and I ...
- 1,937
6
votes
1
answer
340
views
Shouldn't Infinite Past be smaller than all other dates?
Max of Infinite past and a finite time gives Infinite past.
Max[DateObject[{-\[Infinity],1,1},"Day"],DateObject[{2023,7,1},"Day"]]
DateObject[{...
- 9,043
1
vote
0
answers
46
views
Printout precision [closed]
For debugging, I print out the SessionTime. In the Notebook it looks like:
...
- 1,141
5
votes
4
answers
238
views
Working directly on DateObjects
This relates to an earlier question I asked some years ago, From a list of dates, get a list of the last date available in each month.
In this case, I have a list of business dates (no weekends or ...
- 14.3k
2
votes
1
answer
51
views
Multiplication counting to illustrate HornerForm
HornerForm[] converts a polynomial with integer exponents into an equivalent polynomial that requires fewer total multiplications. (It also has the benefit of ...
- 39.6k
3
votes
1
answer
53
views
Export and Import DateObjects
I have a number of long lists of DateObjects paired with values.
An example data element looks like this:
It takes several hours of processing time to generate ...
- 14.3k
1
vote
1
answer
66
views
Adding error bars on x axis in DateListPlot
Is it possible to add error bars in the x direction in a DateListPlot? It seems that a naive application of Around in this case ...
- 6,525
4
votes
2
answers
143
views
Pair monthly data with daily data
I need to pair 30-year treasury yield data (only available monthly) to S&P500 data of the same dates.
Treasury data WolframAlpha accesses from the St. Louis Federal Reserve comes down with dates ...
- 14.3k
0
votes
0
answers
48
views
Force time series to drop the date part and keep only the time one
Mathematica's TimeSeries takes as an input the values and the time.
If I have a TimeObject with timestamps (without the date, ...
- 56
1
vote
1
answer
68
views
Coloring Points in a DateListPlot
I want to plot a time series so that positive values appear in red and negative values in green.
I have tried all kind of variants of the following, which just plots everything in the last color ...
- 379
1
vote
1
answer
72
views
How to change the background color of DateObject?
Recently I encountered a situation where I would like to distinguish between different DateObjects for a visual appearance for presentation.
For now, I am using
<...
- 9,043
1
vote
0
answers
38
views
DateFormat for ISO8601 string with TimeZone?
What is the DateFormat to convert ISO8601 string with timezone to DateObject?
For exmaple,
...
- 15k
2
votes
2
answers
89
views
Holiday names from HolidayCalendar?
HolidayCalendar doc outputs aholiday dates as DateObject list based on a date range.
Is there a method or Entity to map to names,...
- 15k
1
vote
1
answer
191
views
Is there any hope to get the result faster if we use a supercomputer for the given problem?
If an operation in Mathematica (say, computing the determinant of a $88\times88$ parametric matrix) takes much time to be computed on a personal computer (core i7), say a week, then, is there any hope ...
- 1,159
0
votes
2
answers
135
views
Solving a system of equations takes too long [closed]
I was trying to solve a system of 4 equations with Mathematica but it took too long (running for hours) without any output. I have tried many ways without any success. I need your help. Thank you in ...
- 21
3
votes
3
answers
130
views
6
votes
1
answer
138
views
How can I tell the WL auto-magic date interpreter to use a day-first interpretation if there is ambiguity?
I know you can use DateObject[{"05-08-2022", {"Day", "Month", "Year" }}] to tell WL the date format explicitly, but a rigid ...
- 21.6k
2
votes
2
answers
55
views
DayMatchQ Alternative day name specification
Not clear from DayMatchQ doc page but doesn't seem to work for say alternatives the way MatchQ does, eg
...
- 15k
0
votes
1
answer
70
views
List structure for plotting multiple y-values (with gaps on certain dates) using DateListPlot
I would like to set up a list like this
data = {{Date1,y1,y2,y3,y4,y5,y6},{Date2,y1,y2,y3,y4,y5,y6},...}
and then use DateListPlot to create various plots, e.g. y1 ...
5
votes
1
answer
90
views
Reduce granularity and remove options from a DateObject
I have a DateObject with lots of granularity and additional specifications, such as the following e.g.:
...
0
votes
0
answers
56
views
Can I use Timeseries of a Data to plot the ARCHProcess?
So,
I have a list
s={Timeseries1,Timeseries2,Timeseris3}
I want to Plot a graph just like :Mathematica
I tried to do this but I didn't understand some parts of the ...
7
votes
2
answers
157
views
What's the reverse of DateValue[..., "YearExact"]?
DateValue[..., "YearExact"] can be used to get a date as an non-integer year. This can be useful for some quick, not necessarily too precise calculations ...
- 18.6k
1
vote
1
answer
191
views
AbsoluteTime::ambig: Warning: the interpretation of the string 11-12-2020 as a date is ambiguous
TScci30clean = TimeSeries[cci30clean[[2 ;;]]]
I dont understand why this shows an error ,i have changed the date format twice in excel sheet that im working on ...
0
votes
0
answers
53
views
Why is the DateInterval not handling disjoint periods correctly?
Consider the following as an example:
...
- 9,043
3
votes
1
answer
72
views
How do I import a file only when it is modified?
I am trying to create a Dynamic code that will Import the contents of file only if it has been modified. I tried the following ...
- 9,043
6
votes
1
answer
114
views
Changing callout sizes in TimelinePlot
I have a large, complex TimelinePlot in which the callout bubbles are too large, as shown here:
I'm happy with the font size and layout, but the bounding panes should be reduced (vertically) by a ...
- 39.6k
1
vote
1
answer
68
views
Federal Reserve Interest Rate Data has years with differing number of weeks
I need to compute annual mean interest rates from public data. FRED mortgage rate data (available here: https://fred.stlouisfed.org/series/MORTGAGE30US) when downloaded as an Excel file, Imports as ...
- 790
2
votes
1
answer
123
views
How to import CSV file with mixed data, including string Mathematica expressions and numbers
I am importing a CSV file that looks like this (Extract of data as viewed in Notepad):
...
- 73
0
votes
1
answer
68
views
4
votes
2
answers
85
views
Format Time Reported by AbsoluteTiming
I am trying to format the timing reported by AbsoluteTiming so that it states the hours minutes and seconds of the result. However, probably because ...
- 1,951
0
votes
0
answers
44
views
DateFormat to display DateObject sub-second data?
Is there a DateFormat or other option to display milliseconds?
DateObject["2022-04-18T14:02:10.326"]
Sub-second ...
- 15k
3
votes
1
answer
145
views
Changing weekend definition
How to change the definition of 'Weekend' to get 'True' from every Friday from 22:00:01 to Sunday 23:00:00. Example:
...
- 1,019
1
vote
2
answers
205
views
Convert clock time to seconds [duplicate]
I have a long list with time values in the format Hours:minutes:Seconds.
How can I convert the time back to seconds?
For example (for seconds it also have a decimal fraction)
...
- 297
1
vote
1
answer
46
views
`DateList` hour format
I cannot find it in the documentation, what is the default form of hour in the DateList when the form {y,m,d,h,m,s} is used. I ...
- 3,703
4
votes
2
answers
110
views
DateHistogram with DateReduction -> editing x axis
I have a list of dates spanning over multiple years (i.e.):
...
- 43
0
votes
2
answers
78
views
DateListPlot if condition is fulfilled
This must be very simple but I could not find an appropriate answer. I have imported a huge .xlsx file with three columns: country name, date and a value and I would like to DateListPlot the values ...
5
votes
2
answers
176
views
Marking day versus night in DateListPlot
I would like to mark the periods of day versus night on a DateListPlot (and associated plots) by light gray regions for the night. Here's a minimal example that ...
- 39.6k
13
votes
9
answers
2k
views
How to split a number
I have a number representing date (yyyymmdd):
19001231
I want to convert this number to
{1900,12,31}
How to do this? There ...
- 405
7
votes
3
answers
244
views
Tick marks for datelistplot
I have this data and I want to plot it with six dates on the x-axis. The first tick should be the first data points date minus two days and the last tick should be the last data points date plus two ...
- 81
1
vote
1
answer
92
views
a possible bug in IntervalUnion when applied to DateInterval
Bug introduced in 13.0 or earlier and persisting through 13.2.0 or later.
It seems IntervalUnion may lead to unexpected results when applied to ...
- 4,317
5
votes
2
answers
137
views
4
votes
3
answers
191
views
Finding the index of certain strings in a list
I'm actually using a dataset of much greater dimensions and length but I simplified my problem of string patterns in order to ask this question.
...
- 1,156
11
votes
1
answer
314
views
Incorrect behavior of TimeObject in version 13
I used to use TimeObject in my code and pass it the string coming from a database system as follows and it used to convert it to the correct time.
...
- 9,043