## 192 Reputation

17 years, 39 days

## How and why did Maple do this Sum correc...

Maple 2019

1. How did Maple come up with this answer?

I've tried all the packages in SumTools and none of them give an answer except Hypergeometric.

2. Is there a way to trace the steps Maple is using so I can try and answer this myself?

3. Why did it sum the series when I didn't even ask - I deliberately used the inert form (no arguments though - I like what it did).

Thank you.

______________________________________________________________________________

H1a := Sum(GAMMA(2*b - 1 + 2*n)*GAMMA(2*n - s)*(b - 1/2 + 2*n)/(GAMMA(2*b + 2*n + s)*GAMMA(2*n + 1)), n = 0 .. infinity);

H1b:=convert(H1a,Hypergeom);

The answer H1b it came up with is

GAMMA(-s)*2^(1 + 2*b)*GAMMA(b)/(8*GAMMA(b + s)*2^(2*b));

which seems to be correct.

## Maple Crash wipes out initialization and...

Maple 2019

Hi:

Every once-in-a-while Maple crashes due to a bug in numerical integration that I reported ages ago, but was never fixed (or if it was, I was never told). Anyway, this time, in addition to crashing, it wiped out my worksheet, and froze the machine. When I recovered, Maple had lost all memory of my preferences, recent files, etc - it was as if I had a clean installation.

I restored the link to the usual style file I use, but it still refuses to give me back the style I want - that is - the classical worksheet. Every command I enter now requires F5 or I will get 2D input which I hate. Does anyone know where the preferences, probably an .INI file, are kept, so I can restore it from an older version of Maple.

Thank you

## Inverse Laplace Transform sort of works ...

Maple 2019

Here are 4 statements that attempt to use invlaplace on the exponential function. Two work, two don't.

Does anyone know why the two that don't work do that?

Thank you.

__________________________

with(inttrans);
[addtable, fourier, fouriercos, fouriersin, hankel, hilbert,   invfourier, invhilbert, invlaplace, invmellin, laplace, mellin,   savetable]
invlaplace(exp(-s),s,t);
Dirac(t - 1)
invlaplace(exp(s),s,t);
invlaplace(exp(s), s, t)
invlaplace(exp(s),s,t) assuming s<0,s::real;
invlaplace(exp(s), s, t)

invlaplace(exp(-s),s,t) assuming s<0,s::real;
Dirac(t - 1)
What is going on here?

## Maple 2016 fails after latest Windows 10...

Maple 2016

Maple 2016 worked fine on July 27.

On July 28 Microsoft insisted on applying a patch to Windows 10 (they called it a "significant upgrade"). After that, Maple 2016 no longer works - it loads, presents the default worksheet, allows you to load a previous worksheet, but as soon as you go to do anything, it quits.

Any suggestions, other than downgrading to the previous version of Windows 10, which I have already done, (and turned off MS windows update services)?

## How to retain an executed worksheet...

Maple

I've got a worksheet in which I have invested many hours of CPU execution time and if the computer goes down, or Maple fails for some reason, I'll lose it all.

If this happens I would like to be able to continue the calculation from where I left off.

By saving the worksheet periodically, I can save all the commands, but not the results, so if I have to restart, I'll have to wait many hours before the worksheet catches up to where it left off.

In ancient versions of Maple, you used to be able to save an executed worksheet including results (I sort of remember that you wrote a file with the extension ".M")  but the new help pages say that is now different from what it used to be. Obviously I can "save" individual symbols to a file, but for a complicated worksheet  that gets complicated.

I've read about "maplet" files, but that doesn't seem to fill the bill either.

So, is there any simple way to save a worksheet so you can continue seamlessly from where you left off after a crash, with all the previous results intact?

 1 2 3 4 5 6 7 Page 1 of 7
﻿