## How to solve transcendental equation exactly?...

I mean the root of the equation

GAMMA(n-1/n)*GAMMA(1/n)/(n*GAMMA(n)) = 1

belonging to RealRange(Open(1),4). It should be noticed there are solutions outside this interval. Here is my try.

 (1)

 (2)

Also

 (3)

There is a substitute

 (4)

 (5)

There is a shade of hope that GAMMA(n-1/n)*GAMMA(1/n)/(n*GAMMA(n))  can be simplified.

PS. An SCR was submitted by me.

## Product simplification fails...

The following product

(product(mu^x[i]/factorial(x[i]), i = 1 .. n))

does not simplify to the most obvious form whatever I try

mu^(sum(x[i], i = 1 .. n))/(product(factorial(x[i]), i = 1 .. n))

What can it be?

## Iterator[CartesianProduct], option rank...

It seems to be a bug here:

restart;
with(Iterator):
M := CartesianProduct([1,2],[a,b],[c,d,e], rank=3):
n:=0:  for v in M do n:=n+1: print(n,v); end do:

1, [2   b   c]
2, [2   b   d]
Error, (in unknown) improper op or subscript selector

# for rank=9  ==>  [list, b, e]     ??

## time series troubles...

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.

best regards

Andras

Time_Series_Data.xlsx

TimeSeriesTest.mw

## maple 2016 JAVA crash....

Hello,

I'm stuck with maple 2016 as it crashes after a few minutes use.

it did work for a few weeks. It appears that its java crashing,

ive been given no error code or anything. uninstalling java and reinstaling did work.

im running the proper bit version. (64) rollio

tried backrolling windows, didnt work.

tried running it as Administrator no luck, ran it on backward compatibility windows 8 and 7.

ive run out of ideas the last option seems to be a clean windows install.

any help would be greatly appreciated.

the laptop in question (HP notebook 15-ba005no)

runs windows 10 (64bit)

8gigs of ram

cpu AMD E2-7110 1.8 GHz

128 GB SSD

dkdwarf.

## removing rows, or columns from a DataFrame...

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?

best regards

Andras

## Finite Difference Method for PDE...

Dear all

I have a PDE and its analytical solution. I want to find the numerical solution by Finite Difference Method.

I duscratize the PDE and boundary condition and Could not able to solve them togethe.

Here is the file FEM-Nu.mw

## How to find the Taylor expansion...

of the implicit function sin(x+y)+sin(x) = y at x = Pi , y=0 of order 15? Here is one of the difficulties

restart; eval(implicitdiff(sin(x+y)+sin(x) = y, y, x\$15), [x = Pi, y = 0]);
Error, (in expand/bigprod) Maple was unable to allocate enough memory to complete this computation. Please see ?alloc

hi

thanks

dsove2.mw

 >
 >
 >
 (1)
 >
 >
 >
 >
 >
 >

## Asymptotics of certain subsets number...

Let us denote the cardinality of the subsets of {1,..,n} without two consequent numbers
(e.g. {..,4,5,..} is not allowed) by A[n]. What is the asymptotics of A[n] as n approaches infinity?
The same question for the case of three consequent numbers.
Here is my math experiment.
restart; L := combinat:-powerset({seq(i, i = 1 .. 11)}):#n = 11
nops(%);
2048
M := selectremove(c-> min([seq(c[k+1]-c[k], k = 1 .. nops(c)-1)]) = 1, L)[2]:
nops(M);
233
The other results are [11, 233], [15, 1597], [20, 17711], [21, 28657], [22, 46368].
These points are very close to some straight line in logarithmic scale as
plot([[11, 233], [15, 1597], [20, 17711], [21, 28657], [22, 46368]], axis[2] = [mode = log]);
shows. However, the ones do not exactly belong to a straight line:
evalf(ln(46368)-ln(28657), 15);
0.4812118247230
evalf(ln(28657)-ln(17711), 15);
0.48121182594077
eval(exp(.4812118247230*n), n = 15);
1364.000725  .
These results suggest that A[n] is asymptotically equal to exp(c*n) with c about 0.481.
I have not succeeded to find out the nature of the constant c.

question_on_asymptotics.mw

## logarithmic derivative...

Hello people in mapleprimes,

I want to ask you about how to make a function of function which makes a logarithmic derivative of a function.

For example, x^3 is mapped as h(x^3)=3h(x), h(x+y)=(x/(x+y))*h(x)+(y/(x+y))*h(y),

h(g(x)*k(x))=h(g(x))+h(k(x)).

I hope someone give me a hing to create h.

Best wishes.

taro

## Maple 2016 installation hangs on silent installati...

environment
- Windows 10 LTSB 64-bit
- Intel Haswell/Skylake

sequence:
1. install Windows unattended
2. install scheduletask for software installation (runs with systemaccount on windows starts and available network)
3. task runs a cmdfile(1) that map a networkshare and runs another cmdfile(2) on the networkshare
4. cmdfile(2) runs softwareinstallation one by one, every install is a seperate cmdfile
5. cmfile(maple.cmd) starts maple installation with the following cmdline
-->
START "Maple 2016" /WAIT "N:\Math\Maple\Maple2016Windowsx86Installer.exe" --mode unattended --desktopshortcut 0 --shortcutname "Maple 2016" --configureMatlab 0 --matlabpath "" --licenseType network --serverName "licserver.company.domain" --portnumber 27000
<--

Note: licenseserver and port are configured correctly, tested with manual installation of Maple

effects:
- installer starts and install some files (found unter C:\ProgramFiles\Maple 2016)
- installer persists in memory
- no startmenuentry for maple found
- no installler logfile in maple directory found
- install not finished

- try it with --optionfile ... -> hangs
- try copying all files to local harddisk and run it from there -> hangs
- try it running with a local administrator (using psexec) -> hangs

- if im logged in and run the installer cmdline manually with adminconsole or with systemaccount (psexec -i -s -d cmd) the installation runs perfect, but this is not what i need to install hundreds of machines

## difficulty with the Explore command...

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

## Why wouldn't subs work?...

Hello people in maple primes

I have a question, which is about the matrix shown in http://www.mapleprimes.com/questions/217852-HOW-I-Convert-Root-Of-In-To-Another-Common-Form

Why can't C below be shown with beta?

A := Matrix(3, 3, [[-a, a, 0], [0, 0, -sqrt(l*b*c*(j+k))/(j+k)], [2*j*sqrt(l*b*c*(j+k))/((j+k)*l), 2*k*sqrt(l*b*c*(j+k))/((j+k)*l), -c]]);
B:=subs(l*b*c*(j+k)=alpha,A);
C:=subs(j*alpha^(1/2) = beta,B);
e:=subs(alpha^(1/2) = gamma,B);

Best wishes.

taro

## difficulties evaluating an infinite integral...

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

 First 28 29 30 31 32 33 34 Last Page 30 of 43
﻿