## How should I save a procedure and read it into a ...

I have a module with quite a few procedures and it is getting too long and complex. Basicially I write each procedure in a seperate document, them copy and paste it into the module. I want to improve matters as save each proc and read it in to the module

e.g.  Qdim:=proc(A,B).........end proc

save Qdim , "Qdim.?"   have tried .txt ,.mla , .m  They save fine.

in the module have tried

read "Qdim.txt" etc.   I have included Qdim in export but Qdim doesnt work Qdim(A,B) returns Qdim(A,B)

which procuces an error

Error, (in unknown) could not open C:UsersRonanDocumentsMAPLERational TrinonometryQdim.m for reading

## prime notation setup changed in Maple 2017...

Not sure if this is documented explicitly to Maple users, but normally (prior to Maple 2017) interface(typesetting=extended) was all that was required to output display diff(y(x),x) as y'(x)

With Maple 2017 typesetting=extended is default and one must use with(Typesetting)  Settings(typesetprime=true) in order to output the display of diff(y(x),x) as y'(x).

Perhaps this is well documented somewhere, however I was unable to find the change.

## Problems with units in fsolve...

I am new to Maple and I am trying to add units to the "Flow Through an Expansion Valve" Application Demonstration.  I was trying pressure in [PSI], temperature in [degC] and flow rate in [kg/hour] everything else in SI units.  I included with(Units:-Standard) but had no luck with the fsolve function.

Any chance someone could make a version of this demonstration applicaton that includes units?

Thanks

## How to get asymptotic solutions?...

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> restart; with(PDETools), with(plots);
> n := .3; Pr := 7; Da := 0.1e-4; Nb := .1; Nt := .1; tau := 5;
> Eq1 := (1-n)*(diff(f(x, y), $(y, 3)))+(1+x*cot(x))*f(x, y)*(diff(f(x, y), $(y, 2)))-(diff(f(x, y), y))/Da+(diff(f(x, y), y))^2+n*We*(diff(f(x, y), $(y, 2)))*(diff(f(x, y), $(y, 3)))+sin(x)*(theta(x, y)+phi(x, y))/x = x*((diff(f(x, y), y))*(diff(f(x, y), y, x))+(diff(f(x, y), $(y, 2)))*(diff(f(x, y), x))); > Eq2 := (diff(theta(x, y), $(y, 2)))/Pr+Nt*(diff(theta(x, y), y))^2/Pr+Nb*(diff(phi(x, y), y))*(diff(theta(x, y), y))/Pr+(1+x*cot(x))*f(x, y)*(diff(theta(x, y), y)) = x*((diff(f(x, y), y))*(diff(theta(x, y), x))+(diff(theta(x, y), y))*(diff(f(x, y), x)));
> Eq3 := Nb*(diff(phi(x, y), $(y, 2)))/(tau*Pr)+Nt*(diff(theta(x, y), $(y, 2)))/(tau*Pr)+(1+x*cot(x))*f(x, y)*(diff(phi(x, y), y)) = x*((diff(f(x, y), y))*(diff(phi(x, y), x))+(diff(phi(x, y), y))*(diff(f(x, y), x)));
> ValWe := [0, 5, 10];
> bcs := {Nb*(D[2](phi))(x, 0)+Nt*(D[2](theta))(x, 0) = 0, f(0, y) = ((1/12)*y)^2*(6-8*((1/12)*y)+3*((1/12)*y)^2), f(x, 0) = 0, phi(0, y) = -.5*y, phi(x, 12) = 0, theta(0, y) = (1-(1/12)*y)^2, theta(x, 0) = 1, theta(x, 12) = 0, (D[2](f))(x, 0) = Da^(1/2)*(D[2, 2](f))(x, 0)+Da*(D[2, 2, 2](f))(x, 0), (D[2](f))(x, 12) = 0};
> pdsys := {Eq1, Eq2, Eq3}; for i to 3 do We := ValWe[i]; ans[i] := pdsolve(pdsys, bcs, numeric) end do;
> p1 := ans[1]:-plot(theta(x, y), x = 1, color = blue); p2 := ans[2]:-plot(theta(x, y), x = 1, color = green); p3 := ans[3]:-plot(theta(x, y), x = 1, color = black);
> plots[display]({p1, p2, p3});

## make latex() generate y'(x) for diff(y(x),x) ?...

I know the latex() command in Maple have many issues and I have no hope of what I will ask having a solution, but thought to ask any way.

Is there a way to make maple generate the latex for all the derivatives to use ' instead of d/dx ?

for example, given this

ode:=diff(y(x),x)=x;
latex(ode,output=string);


The Latex generated (which is correct) is

{\frac {\rm d}{{\rm d}x}}y \left( x \right) =x

but sometines I find it more readable if the latex was

y'(x)=x

which is more common in textbooks and other places. The problem also is that I am using worksheet so can't use  y'(x) as input.

But even switching to document mode, and writing it 2D math as input, the Latex output still does not match the input

So if there is a solution to this, would it require changing the latex() command itself? or can it be done at user level?

I'd like all orders of derivatives anywhere in the equation to come out as y'' etc.. so diff(y(x),x\$3) should generate the latex y'''(x) and so on.

Is there a trick to do this?

Maple 2017.2

## How do you access the number that an expression ev...

I am trying to solve a system of equations (I'm using MapleTA< but I'm pretty sure that this applies to any Maple product).  I have successfully solved the system, and obtain a set of solutions, which has name Soln.  I can access the element Soln[1], which is an expression:

vn2 = 12/7

Now, I just want that 12/7, as a decimal.  I try evalf(Soln[1]), but again I end up with vn2 = 12/7.  How do I get the decimal number out, without it being an expression?

## a mathematical question about a continuous functio...

on the basis of Fundamental theorem of calculus, the function " f " has Antiderivative F , whichi F is continuous and differentiabe in the range of integration, i have a question ? if function f has an Antiderivative F, should it be also continuous and differentiabe in that range? in the picture below it says "when f is continuous", can f be discontinuous? how it can be ? any examples?

## Is there something like convert/elsymfun for polyn...

Using convert(f,elsymfun) when f is a symmetric polynomial will write it in terms of elementary symmetric polynomials. For example, x^2+y^2 would become (x+y)^2-2x*y. For this command not to return an error, f must be symmetric, equivalently of type symmfunc(all indeterminants in expression).

I'd like to use this in a broader sense, when there are extra variables hanging around. For example, suppose f is a polynomial in a,b,c,x,y,z, and symmetric in x,y,z, so that type(f,symmfunc(x,y,z)) returns true. Then it is still possible to write this in terms of the elementary symmetric polynomials on x,y,z (with coefficients taken being rational polynomials in a,b,c).

For example, a+x^2+y^2 can be written as a+(x+y)^2-2x*y.

Is there a command available for this? Or is there a roundabout way to make Maple forget temporarily that a,b,c are indeterminants, before putting them back in after?

Thanks

## How to obtain random decimal numbers...

Is there a simple command to generate decimal numbers in a given range?

For example, I wish to obtain a randomly generated number between, say ... -0.5 and 0.5.

## Changing coordinates for matrix plot...

I'm plotting matrices using the proc in the attached file.

How do I move the rows in the plot closer to each other?
The first picture show the rows plotted in the values [13,14...19].
I want them to be plotted in values like [13,13.5,14,14.5...].

Second picture shows how I would like it to be. Created it in paint, from a different matrix.Matrix_plot.mw

## schmitt trigger...

hi..

I dont know why ''Y'' in this code does not calculate?

Also in Determinant  should exist term ''Omega''!!!

however this term not apear!!

thanksZrO2.mw

 >
 > with(LinearAlgebra):
 > with(LinearAlgebra):
 > with(VectorCalculus):
 > E_c:=200e9:
 > rho_m:=2702:
 > rho_c:=5700:h:=1:Digits:=200:

## "unable to convert to an explicit first-order syst...

hi... I have a problem with dsolve.

"unable to convert to an explicit first-order system"

thanks

## How to calculate the projection onto a surface?...

I'm trying project a plane onto a surface. Is there a direct command to do this?. There is a command to project a surface onto a plane but i need the oposite. Thanks!