Maple 2019 Questions and Posts

These are Posts and Questions associated with the product, Maple 2019

Maple 2018 and earlier displayed an Array like this

In Maple 2019 I get this

How do I display Arrays in Maple 2019 like Maple 2018?

How Do I set the Command Line Font in Maple 2019?

The default font is strange.  eq is displayed as a a lower case char like '8' followed by 'q'.

I would like to have something like courier 10, etc.

Hi, I am using the GroupTheory package and I wanted to created the following group in Maple:

I stumbled across this link https://www.maplesoft.com/products/maple/features/grouptheory.aspx and then tried to use the following commands to define this group in Maple:

1. First a defined a 12x12 matrix:

ct := <<e | p | q | r | s | t | u | v | w | x | y | z>, <p | q | e | y | u | w | z | r | x | t | v | s>, <q | e | p | v | z | x | s | y | t | w | r | u>, <r | z | t | s | e | y | v | x | p | u | q | w>, <s | w | y | e | r | q | x | u | z | v | t | p>, <t | r | z | x | w | u | e | q | y | p | s | v>, <u | x | v | p | y | e | t | z | s | r | w | q>, <v | u | x | z | q | r | y | w | e | s | p | t>, <w | y | s | t | x | z | p | e | v | q | u | r>, <x | v | u | w | t | s | q | p | r | e | z | y>, <y | s | w | u | p | v | r | t | q | z | e | x>, <z | t | r | q | v | p | w | s | u | y | x | e>>

 

2. Then I tried to define my  group using:

G := Group(ct)

 

However this doesn't work because I get the following error:

Error, (in GroupTheory:-Group) invalid input: arguments to GroupTheory:-Group, [Matrix(12, 12, {(1, 1) = e, (1, 2) = p, (1, 3) = q, (1, 4) = r, (1, 5) = s, (1, 6) = t, (1, 7) = u, (1, 8) = v, (1, 9) = w, (1, 10) = x, (1, 11) = y, (1, 12) = z, (2, 1) = p, (2, 2) = q, (2, 3) = e, (2, 4) = y, (2, 5) = u, (2, 6) = w, (2, 7) = z, (2, 8) = r, (2, 9) = x, (2, 10) = t, (2, 11) = v, (2, 12) = s, (3, 1) = q, (3, 2) = e, (3, 3) = p, (3, 4) = v, (3, 5) = z, (3, 6) = x, (3, 7) = s, (3, 8) = y, (3, 9) = t, (3, 10) = w, (3, 11) = r, (3, 12) = u, (4, 1) = r, (4, 2) = z, (4, 3) = t, (4, 4) = s, (4, 5) = e, (4, 6) = y, (4, 7) = v, (4, 8) = x, (4, 9) = p, (4, 10) = ...  (12, 8) = s, (12, 9) = u, (12, 10) = y, (12, 11) = x, (12, 12) = e})], do not match any of the accepted calling sequences

 

I don't know what's going wrong. It doesn't give a 2D Plot. Thanks in advance.

Temperature over 24hr period

 

y := 0.26e-1*x^3-1.03*x^2+10.2*x+34, 0 <= x and x <= 24

``

``

 

NULL


 

Download temperature24hr.mw

I'm using variable names that have subscripts, not as a table index but literal i.e. R__1 as a unique variable name.  It seems whenever I make assumptions on variables that have subscripts, when I use them the variables that have subscripts are printed twice:

 

Can anyone explain why this happens and how to get around it?

 

Thanks in advance.

alternatingseries.mw
I have a double about this alternating series.
According to maple this series converges:

evalf(sum((-1)^(n+1)*(ln(n)/n+1),n=1..infinity))
                          0.3401310963

However limit ln(n)/n + 1 does not equal to zero, it equals 1. Therefore the series should diverge.

Also while I am on the subject of series and limits, why is limit (-1)^n  as n goes to infinity a range between -1-I and 1 + I.

limit((-1)^(n), n=infinity)
                        -1 - I .. 1 + I

 

 

Hello, I am having a bit of difficulty simplifying some calculations in Maple 2019. In short, in order to verify that the tensors that I am trying to use are indeed inverses of each other, I am simply trying to multiply component wise, for example the tensor component e[2,~2] with the tensor component f[~2,2], since they are essentially inverses of each other, i.e. the matrix defining f is actually the inverse of the matrix e, i.e. f=e^(-1), should give back 1 as an answer. Nonetheless, when I attempt to take this simple multiplication Maple does not reduce it, but rather just gives multiplies the terms with no simplification. Is there anything I can do so that Maple may simplify its calculations? I have already tried the "eval" calling sequence but that didn't do the trick, and I fear that when escalating the calculations I will get a bunch of long expressions rather than concise solutions. Thank you for your help in advance,
 

Christoffel_symbols_of_de_Sitter_metric_research.mw

restart;
with(LinearAlgebra);
G := Matrix([[beta1^2, 0, -beta2^2, 0], [0, beta1*(b^2 - beta1^2), 0, beta2*(b^2 + beta2^2)], [beta1^2*cosh(beta1*l), beta1^2*sinh(beta1*l), -beta2^2*cos(beta2*l), -beta2^2*sin(beta2*l)], [beta1*sinh(beta1*l)*(b^2 - beta1^2), beta1*cosh(beta1*l)*(b^2 - beta1^2), -beta2*sin(beta2*l)*(b^2 - beta2^2), beta2*cos(beta2*l)*(b^2 + beta2^2)]]);
NULL;
NULL;
S := Determinant(G);
S := simplify(S);
S1 := S/(beta1^2*beta2^2);
F := Pi*d^2/4;
Q := F*d^2/8;
u := E/(2*(1 + v));
lambda := sqrt(w^2/c^2);
j := v*d*lambda/sqrt(8);
y1 := 1 - j^2 + sqrt((j^2 - 1)^2 + 4*j^2*u/(c^2*p))/(2*j^2*u/(c^2*lambda^2*p));
y2 := 1 - j^2 - sqrt((j^2 - 1)^2 + 4*j^2*u/(c^2*p))/(2*j^2*u/(c^2*lambda^2*p));
b := 2*(1 + v)*(8/(v^2*d^2) - w^2/c^2);
beta1 := sqrt(y1);
beta2 := sqrt(-y2);
S;
d := 24.8;
c := 5100;
v := 0.34;
l := 2000;
E := 2.1*10^5;
p := 7700;
S;
plot(S, w = 0*2*Pi .. 100000*2*Pi);

# Here I get an error

Error, (in plot) incorrect first argument (-HFloat(2.757556062608314e294)-HFloat(2.757556062608314e294)*I)*(HFloat(2.757556062608314e294)-HFloat(2.757556062608314e294)*I+(HFloat(2.918216722364015e-174)+HFloat(7.045198389075166e-174)*I)*(HFloat(1.2899139595562734e220)+HFloat(1.2899139595562734e220)*I+(HFloat(2.345679734289597e162)+HFloat(9.71612358926469e161)*I)*(.3015529528-0.1030372934e-6*w^2)^2)+(HFloat(2.739493386336394e-116)+HFloat(2.739493386336394e-116)*I)*(HFloat(1.5009648027561687e-231)-HFloat(2.757556062608314e294)*I+(-HFloat(5.478986772672788e-116)+HFloat(5.478986772672788e-116)*I)*(.3015529528-0.103 ... HFloat(2.739493386336394e-116)*I)*(.3015529528-0.1030372934e-6*w^2)^4)

w1 := fsolve(S, w = 0*2*Pi .. 100000*2*Pi);

# Here I get an error 

Error, (in fsolve) Digits cannot exceed 38654705646
 

Is it italic when copied and pasted?  Is it bold when copied from maple 8?  I just ahve not been able to work it out.

The only way that I can think of doing it is by multiplying by a tetrad.  Even then it does not work well see my worksheet:  The Dirac Equation in Robertson-Walker spacetime.

 Recently I often drew some graphs in Graph Theory  by Maple. I tried to use DrawGraph, but  I found that evey edge only meets straight line  style in this package.

For example: 

restart:
with(GraphTheory):
with(SpecialGraphs):
a:=CycleGraph(8):
DrawGraph(a)

 

How do I draw some edges with curve syle in graph? like following:

 

 

 

Thanks!

 

 

 


 

Function Misrepresented

y^2-x = 1"(->)"[[y = (x+1)^(1/2)], [y = -(x+1)^(1/2)]]NULL

NULL

 

Expected output for y

 

y = `&+-`(sqrt(1+x))

 

Yes it's the same meaning but i would like less to look at.


 

Download funct_misrep.mw

Hi! 

 

I'm having a weird issue. :( 

DEplot command worked when I initially ran the executed it, but then when I executed the entire worksheet, it didn't plot. Instead I just get this output. 

 

This is the entire worksheet so far without the output. 

 

If someone could please help me, I would greatly appreciate it!!!!!

 


restart;
with(DEtools);

eq1 := diff(y(x), x) = 3*x*y(x);

dsolve(eq1, y(x));

ini1 := y(0) = 3;

dsolve({eq1, ini1}, y(x));

ini2 := y(1) = -3;

dsolve({eq1, ini2}, y(x));

eq2 := y(x)*diff(y(x), x) = -x;

dsolve(eq2, y(x));

dsolve({eq2, ini1}, y(x));

restart;
with(plots);

eq := diff(y(x), x) = 3*x*y(x);

ini := y(0) = 5;


dsolve({eq, ini}, y(x));




sol := rhs(%);

plot(sol, x = -2 .. 2, y = 0 .. 10);
DEplot(eq, y(x), x = -2 .. 2, y = 0 .. 10, [[ini]]);





 

Hi,

The VectorCalculus package offers a convenient way to compute multivariate integral over a non-square geometry. See help("VectorCalculus/int"). Here is an example taken from this help page:

 

with(VectorCalculus):

int( x*y, [x,y] = Triangle( <0,0>, <1,0>, <0,1> ) );

 

The question is: is there a way to draw the area “Triangle( <0,0>, <1,0>, <0,1> )” in order to quickly check that it matches the expected region of integration that one needs?

I am trying to plot the solution of the DE in the interval [0.3,4]

5 6 7 8 9 10 11 Last Page 7 of 30