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3
votes
2answers
115 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 ...
0
votes
1answer
82 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. ...
1
vote
3answers
156 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 ...
1
vote
0answers
60 views

How to restart a Clock

The code below is to demonstrate color afterimages. The user chooses a color, fixates the changing numbers at the center until they reach 30 (seconds), then manually switches to white to observer the ...
4
votes
3answers
153 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: ...
0
votes
0answers
46 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 ...
1
vote
0answers
49 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. ...
1
vote
1answer
51 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: ...
0
votes
0answers
34 views

how to determine how much time it will take to run a cell exression?

I am trying to find integration of a large matrix. It is taking too much time to do it. because of matrix elements contains trigonomteric expression. 4 days gone, it is still running. I want to know ...
5
votes
4answers
289 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: ...
4
votes
1answer
129 views

Throttle EventHandler KeyReleased

What might be the most elegant way to throttle the a,s functions triggered by an ...
3
votes
0answers
158 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 ...
1
vote
2answers
57 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 ...
-1
votes
1answer
106 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 ...
5
votes
1answer
254 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?
2
votes
0answers
361 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 ...
5
votes
1answer
237 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.
1
vote
1answer
61 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!
2
votes
2answers
366 views

How to create a combined bar plot with time format?

I'm not sure how to add time format to bar plots. I'd like to be able to make one bar plot for one data set and another for another data set and then combine them, but I don't know how to offset each ...
9
votes
2answers
2k views

Measuring execution time of code

How one can measure the execution time (time that is spent for code to finish) of a program in Mathematica? I understand that there are general timing functions (Timing, AbsoluteTiming, TimeUsed, ...
8
votes
2answers
670 views

UNIX time to DateList

I have data that is timestamped with UNIX time, which is the number of seconds since January 1, 1970 UTC. Unfortunately, it seems that most of the date and time functions in Mathematica are based on ...
10
votes
1answer
222 views

TimeConstrained dynamic change of maximum time

I would like to run a time consuming function: TimeConstrained[f[x],maxseconds] and be able to change maxseconds during running (increasing or decreasing max ...
13
votes
4answers
377 views

Does Mathematica support importing ISO 8601 date strings?

Does Mathematica have a built-in function to convert ISO 8601 formatted date strings (e.g. 2012-01-04T00:00:00) to a date list? ISO 8601 strings come in a variety ...