a_simsim

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14 years, 288 days

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These are questions asked by a_simsim

Dear Community,

I have two measured series - time series actually, stored in Excel:

  • gas flow (ordered in ascending date order),
  • pressure measurements (unordered, more or less randomly distributed dates),

I would like to:

  • import the two series into Maple,
  • convert them to time series,
  • merge them in a way, that the unordered pressure dates are plugged into the ordered gas flow dates, so I finally get a single, ordered date sequence of ascending order.
  • pressure and gas flow rates should remain separated of course, i.e. not merged (they should appear in two separate vectors, or matrix columns, whatever)
  • if pressure dates and gas flow dates are the same, they should naturally be in the same row, i.e. belong to the same date.

No problems with the import, but I'm lost with the time series handling. I tried to figure it out from the help, but frankly the description is rather difficult, and I also haven't found appropriate examples. Is it possible to do it with Maple's time series feature at all, or something other is more practical? Files and my initial trial are attached.

tx in advance

best regards

Andras

Time_Series_Data.xlsx

TimeSeriesTest.mw

Dear Community,

Is there an explicit command to remove rows or columns from a DataFrame? I've only found the Append command. What's the easiest way to do it?

Tx in advance,

best regards

Andras

Dear Community,

I have a complicated function with two independent variables, namely QD( tD,  rD ). I would like to explore its behavior in a semilog plot in the range of tD = 1.0 .. 1000.0 with changing rDs, where I would like to change the values of rD with a slider of the Explore command. I've developed the attached code, yet it gives me an error message, "unexpected option... " Could you pls. have a look at it what do I do wrong?

Tx for the kind help in advance

best regards

Andras

 Explore_VEHQD.mw

Dear Community,

 

I have difficulties evaluating a rather complicated infinite integral (see attachment). The result should be something like 12.319. Any idea how to go get this?

Tx for the kind help in advance,

best regards

Andras

Infinite_Integral_2.mw

Dear Community,

I would like to calculate a rather sophisticated function (see it in the attachmenet) Once I try to evaluate it at certain values I get the error message:

"Error (in pD) illegal use of an object as a name" 

What object Maple means? I guess its a minor mistake, yet I'm lost here, and the online help says "There is no help page available for this error"

Tx for the kind help in advance,

Andras

 

Bessel_plot.mw 

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