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Hello,

I want to calculate the IDs product :

Hi

When I export my MapleSim 5 results to a CSV file, I get only 6 digits, I'm looking for effects in the 1/1000 ppm or ppb region, I'm lost here

The global Settings window allows me to adapt epsilon abs and rel, thats nice, but nothing on the data export side.

I find it logical and usefull to have a settings on the export tab to decide on precision, and or selection of time series (usefull if one does not want all data, but just the last 100 values of a loooong run ;)

hi

i have written the followin code that achieve Y from determinant of matric aa. but when i change digit my result changes. i dont know why? 

> restart;
> with(LinearAlgebra);
> Digits := 100;
>
> NULL;
> upsilon := .38;
> rho := 0.122e4;
> l := 0.176e-4;
> h := 2*0.176e-4;
> L := 20*h;
> NULL;
> E := 0.144e10;
> lambda := E*upsilon/((1+upsilon)*(1-2*upsilon));

Dear all,

I have encoutered a funny problem with Optimization package. I minimize some long stuff (lets call it A) and get an answer, e.g.

[.116553990209052046e-19, [n = 4.24568325257496060, rhocut = 1.66125593854788400, m = 2.00000021862965971, rho = .956914761577446150]]

then i just do

evalf(subs(n = 4.24568325257496060, rhocut = 1.66125593854788400, m = 2.00000021862965971, rho = .956914761577446150, A));

and i get

 It seems I can't add a response to this message, so I added some detail to it.

Hello Maple wizards,

I am working with thousands of fairly large (at least 11K nonzero entries) strictly lower triangular Arrays containing positive and negative floating point numbers, including float(1,infinity). The Arrays are the same size and each one can be processed independently, so I hope to avoid a space explosion by having each Array overwrite the previous one -- lhs(entry) and all that. I do see a steady leakage not recovered by gc, but that's not tonight's question.

Hello,

It is obvious why my command

interface(precision=3) 

is not working?. I get 10 decimals(commands below and output in attached file).

I hope it is easy to fix.

Kindest regardsSSSzzzz

Jean-Jacques

restart:
f1 :=  (w1, w2,n) -> add(add(
 `if` (1/2 <= w1+j*w2+((1/n)*(1-w1-w2))*k and
j*w2 +((1/n)*(1-w1-w2))*k < 1/2 ,
(1/((n+1)*(n+2)))*factorial(k+j...

Hi guys,

I've a bad 6x6 matrix, which contains both very big (10^14) and very small (~10) numbers, so that the inversion with digits=15 is pretty bad (if I multiply the inverse by the original one I've offdiagonal elements of the order of 10^6!!!).

I was trying to calculate the Eigenvalues, but something strange happens. With Digits=15

Eigenvalues=  Vector(6, {(1) = -0.2101e-1, (2) = .83693, (3) = 114.86139, (4) = 19791.80546, (5) = 134594000.00000, (6) = 624049000000000.})

with(Optimization); nx := maximize(abs(.5547114632*x^2+1.130478381*x+.9883691714-exp(x)), x = -1 .. 1, location)

nx := 0.4568872387e-1, {[{x = 1.002012310}, 0.4568872387e-1]}

but 1.002 isn't in -1..1

Hello all,

I have encountered a curious bug in the EigenConditionNumbers
procedure. In particular for a pencil pencil (A,B) with B singular,
and precision higher than hardware precision.

The following code for Digits=40 produces a Float(undefined) rather
than a Float(infinity) for the infinite eigenvalue, but an alpha and
beta that will produce an infinite eigenvalue.

Digits:=trunc(evalhf(Digits));
A:=Matrix([[1,0],[0,2]]);
B:=Matrix([[1,0],[0,0]]);

Hello everyone.

When doing calculations in Maple, is it possible to have Maple use some number of significant figures (as set by the Digits=n command) while only showing a specified number in the output? What I would like is a command like the displayprecision one, just with significant figures instead, so I could avoid round-off error, but still only have the relevant number of digits shown.

Thanks in advance.

The MRB constant is defined at http://mathworld.wolfram.com/MRBConstant.html.

In September of 1999, I,Marvin Ray Burns, computed the first 5,000 digits of the MRB Constant on a Pentium II IBM Aptiva 350 (CPU type 66MHz Intel i486DX2) Computer with 64 MB of ram.  

As I have recently learned, the environment variable 'Digits' controls the working precision and is therefore crucial for avoiding significant impacts of round-off error effects on floating point computations.

Moreover I discovered, that even when I set Digits to say 20, Explore is not affected.

Is there a way to control the working precision of the floating-point computations carried out by the Explore option?