## How is this question answered?...

what are the examples of calculating devices and packages?

## unable to evaluate function to numeric values in t...

 > restart:
 > m:=2; k:=75.11; L:=3; a=k-m*L; b:=k+m*L-1;

 > z:=(k*m)/snr;

 > z1:=z^((b+1)/2);

 > x:=z1/(0.693*GAMMA(m*L)*GAMMA(k));

 > me:=MeijerG([[1-a/2,1+a/2,1+(b+1)/2,1+(b+1)/2],[]],[[1+(b+1)/2],[(b+1)/2]],(1/z));

 > cap:=x*me;

 > with(plots):

Warning, the name changecoords has been redefined

 > plot(cap,snr=1..20);

Warning, unable to evaluate the function to numeric values in the region; see the plotting command's help page to ensure the calling sequence is correct

Error, empty plot

 >
 >
 >

Just a begineer in maple and dont know how to rectify this error.

any help..???

## finite summation evaluation...

Need to evaluate above summation in maple. For simplicity infinity can be replaced by some constant say 1000.

The value of parameters used are:

alpha=73.11

beta=76.11

E=4.75

help....

## GAMMA and gamma...

Hello everyone.

need to know what is the difference between use of GAMMA and gamma in maple.

thanks.

## How to Correctly Define Elements of a Matrix Using...

I'm used to Mathcad, and I am very new to Maple. Something I cannot figure out right now is how to define multiple elments of a matrix using a function.

Input Data

Define system dimensions as n:=2;

i:=1..n;

j:=1..n;

lambda:=Matrix(n);

Lambda:=Matrix(n);

upsilon:=vector(n);

Minor side note: I originaly had upsilon defined using the syntax "Vector[row](ncomp)", but this was giving me an 'exponentiation' operation error, so I changed it to what it is now (basically a list/array, which I guess has different type definitions that no longer cause the error?).

lambda[1,2]:=471.0433;

lambda[2,1]:=883.7530;

upsilon[1]:=58.69;

upsilon[2]:=18.07;

The Problem I'm Having

Now I just want to define Lambda using a function to define all elements (like I would in Mathcad).

Lambda[i,j]:= (upsilon[j]/upsilon[i]) * exp (-lambda[i,j]/2853);

which gives me an extremely long error message:

Error, invalid input: exp expects its 1st argument, x, to be of type algebraic, but received Matrix(2, 2, {(1, 1) = -0.3504976272e-3, (1, 2) = -.16509955895845776, (2, 1) = -.30975332953088164, (2, 2) = -0.3504976272e-3}, datatype = float[8]

As far as I can tell (keep in mind that this is my very first Maple project) that it doesn't like lambda as a matrix? But shouldn't it just evaluate to the element? and why is (2,2) and (1,1) giving values, because it should intialize to zero, so exp(0) = 1 in these cases??

I tried to simplify further by just trying

Lambda[i,j]:=(upsilon[j]/upsilon[i]);

but then it just gives me 1, and when I look into Lambda all the elements are now 1 when only the diagnol elements should be 1 (the rest some fractional amount)??

I am at a complete loss. I thought about doing something like For i = 1 to n etc. but then it just looks like coding, which defeats the purpose of trying to make a calculation sheet documenting the procedure...

Any help and/or insights into what I am doing wrong here would be most welcomed :)

P.S. I've just noticed that there is an upload option :/ Wilson_Equation.mw.

## How to solve this problem in Maple？...

I want to get numerical solution of the Eqs.ode(see the folowlling ode and ibc）in Maple.However,when i run the following procedure,it prompts an error "Error, (in dsolve/numeric/bvp) cannot determine a suitable initial profile, please specify an approximate initial solution". How to solve the issue? Please help me.

restart:
n := 1.4; phi := 1; beta := .6931; psi := 1

> restart;
> n := 1.4; phi := 1; beta := .6931; psi := 1;

> s := proc (x) options operator, arrow; evalf(1+(phi*exp(beta*psi)*h(x))^n) end proc;

> Y := proc (x) options operator, arrow; evalf(f-(1/2-(1/2)/n)*ln(s(x))+2*ln(1-(1-s(x))^(-1+1/n))) end proc;

> ode := diff(h(x), `\$`(x, 2))+(diff(Y(x), x))*(diff(h(x), x)+1) = 0;

> ibc := h(0) = 0, ((D(h))(10)+1)*s(10)^(-(1-1/n)*(1/2))*(1-(1-1/s(10))^(1-1/n))^2 = 0;

> p := dsolve({ibc, ode}, numeric);
Error, (in dsolve/numeric/bvp) cannot determine a suitable initial profile, please specify an approximate initial solution
>

I'm not being notified anymore about responses to answers or comments to MaplePrimes. I'm assuming that I'm not the only one (?). This has happened before.

## how to solve this?...

Hy all.

I want to solve this equation, with„dd” as numerical result. What do I do wrong? Thanks. Nico

restart;
TTot := 70;
TC := 17;
GM := .26;
QMax := 870;
V := 3600*GM*QMax*TTot;
eq := V = int(QMax*exp((-t+TC)/dd)*(1+(t-TC)/TC)^(TC/dd), t = 0 .. TTot);
fsolve(eq, dd);

## Implicit Differentiation...

sin(xy) = x + y

subs( y(x)=y, solve( diff(subs( y=y(x), (1) ),x), diff(y(x),x) ) );

-1

subs( x(xy)=x, solve( diff(subs( x=x(xy), (1) ),xy), diff(x(xy),xy) ) );

cos(xy)

1- y cos(xy)

--------------

x cos(xy) - 1

And is there a way that this program can tutor me on how to get this answer intead of spitting out the answer

the diff tutor only allows for a one sided equation to be entered.

## Operational Matrices...

Hi All. Hope all is well.

Assume that we have partitioned [0,a], into N equidistant subintervals and in each subinterval we have M sets of polynomials of arbitrary form[say bij(t)](a.e Taylor series, or Bernstein series,…)

for Example with N=4, M=3 and by Taylor series we have:

now we want to approximate a function, asy f(t), in this interval with following form:

If we have:

(Tau is a constant number)
then: How can  we find L and Z matrices using maple? Is it any way? (or other softwares?)

Regards

Ph.D Candidate

Applied Mathematics Department

## break vertical axis of the graph...

How to make a vertical axis of the plot break?

## gridlines and inlined worksheets

by: Maple , MapleNet , MaplePrimes

For some time I have been running into the problem where uploaded worksheets that are inlined into a Mapleprimes post get gridlines shown, even when they are not specified or shown in the original worksheet. This is a problem because quite often the gridlines make an inlined plot unattractive.

I believe that Mapleprimes uses some version of MapleNet as a mechanism for inlining uploaded worksheets.

It seems that the Standard GUI and/or MapleNet have special handling for gridlines in the sense that they actually distinguish between PLOT structures generated without the `gridlines` option versus those created with `gridlines=false`.  I believe that this has something to do with the persistence of various plot qualities in an output region which (perhaps for historical reasons?)  allow re-execution of a plot input command to produce a plot output rendering that remembers whether gridlines are visible.

If the second plot below does indeed get rendered here in Primes without gridlines visible then one workaround is evident: adding `gridlines=false` instead of omitting the option.

 > plot(sin(x),x=-Pi..Pi);

 > plot(sin(x),x=-Pi..Pi,gridlines=false);

 >

I'll submit a bug report against MapleNet.

acer

## Firefox Question Viewing

by: MaplePrimes

Dear friends.

This is to alert you to a minor problem with your website. I use a variety of operating systems and browsers to access your site. With Firefox 22 and Firefox 26 and OpenSuse 12.2 when I click on a question with a lot of commentary like "Perl vs. Maple (MPF)" from a couple of days ago or "collect x/2-y/2 1/2" the question appears to load for a while but then an empty page appears, containing only the string "2014" and nothing else. Maybe you want to look into this.

Best regards,

Marko Riedel

## Erratic changing of input mode...

Has anyone else seen the following behavior in Maple 16 and/or 17? In worksheet mode, with 2-D math notation, after hitting <enter> to execute a line several times, the software switches, without warning and unrepeatably, to a mode where only the arrows work -and that is to scroll the sheet. This means the <enter> command is no longer recognized.

My only solution has been to click on the line with the mouse, for which it returns to input mode. This behavior started in version 16 and I switched back to 15. However, I prefer features of 17 such as the different subscript options, that I would like to stay in 17.

I note this behavior occurs on both my Windows based machines and have seen it on students' Mac based machines. We use a common site licence at our institution and I wonder if that might be the problem.

In short - it is a pain.

(Yes, I did try to look for other posters with a similar problem, but failed. )