Maple 2019 Questions and Posts

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

E-_Original_RSA.pdf

 

If I want to calculate and know the exact time duration of running step 8, do the current algorithm, 

st := time();

elapsed_time := (time() - st)*sec

is good enough? precise enough? or accurate enough? 

Any other recommendations? 

Ahead of the upcoming deadline 14 jan 2020 for switching from Windows 7 to Windows 10,  I am investigating whether Maple 2019 will run on an HP Stream laptop: Celeron CPU N3060 @ 1.6GHz, RAM 2GB, 64 bit.running Windows 10.

My guess is that the above spec is too low to successfully run Maple 2019.  But if anyone has had success running Maple on a similar spec device please let me know.

Melvin

Hello people :) 

As the captian says, im trying to remove an old task i've made.
But i get this:

Error in Get, invalid object [_XML_reply_data_get("reference" =
"_Maplets_reference_12","parameter" =
"value",_XML_content("Task,UserTasks,Nyops",&Entity "#xc3",&Enity
"#xa6","tning"))]

And i have no idea what it is, but it won't erase my task :'D

Thanks a bunch in advance! 

Have a great weekend you all
Best regards Lucas :)

aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa


Hello. Here is my question.

 

#GIVEN:

ST := [`162` = Record(mu = 475, sigma = 41), `70` = Record(mu = 480, sigma = 42),
       `168` = Record(mu = 448, sigma = 103)]

[`162` = Record(mu = 475, sigma = 41), `70` = Record(mu = 480, sigma = 42), `168` = Record(mu = 448, sigma = 103)]

(1)

Games:=[[`162`, `70`], [`70`, `168`], [`168`, `162`]]

[[`162`, `70`], [`70`, `168`], [`168`, `162`]]

(2)

#I need Maple commands to follow the order of Games to auto create STO please

STO:=[`162` = Record(mu = 475, sigma = 41),`70` = Record(mu = 480, sigma = 42),
       `70` = Record(mu = 480, sigma = 42),`168` = Record(mu = 448, sigma = 103),
     `168` = Record(mu = 448, sigma = 103),`162` = Record(mu = 475, sigma = 41)]

`Non-fatal error while reading data from kernel.`

(3)

 


 

Download ORDERED.mw


I'm trying to evaluate an integral, but after several hours, MAPLE 2019 is unable to return an answer.  My CPU and memory are not being taxed, and the integrand appears well behaved.  Please see below. Any advice?

restart

istar := y*sinh(Pi*y)*exp(-alpha*y^2)*LegendreP(-1/2+I*y, 1+u)

y*sinh(Pi*y)*exp(-alpha*y^2)*LegendreP(-1/2+I*y, 1+u)

(1)

Istar := `assuming`([int(istar, y = 0 .. infinity)], [alpha > 0, u > 0])

int(y*sinh(Pi*y)*exp(-alpha*y^2)*LegendreP(-1/2+I*y, 1+u), y = 0 .. infinity)

(2)

alpha := 1; u := 2

2

(3)

plot(istar, y = 0 .. 40)

 

evalf(Istar)

``


 

Download Istar.mw

 

How I can substitute Eqs1-16) into Eq (17)?

Should I use subs rule?

Thanks 

 

 

A few seconds after calling up Help starts zucking araound and the whole computer then freezes. Ctrl-Alt-Delete doesn't work, hard reset required. Very funny. Am I alone?

Hi

I'm trying to export a file using the .mw file. without a lot of success. Can someone help?

For 1 game, the output is between (8) and (9).

For 2 games. the output is after (17).

TEST.mw

 

Hey guys, 

Is there any way to remove these imaginary parts of the numbers ?

I tried using the RealDomain package in beginning of code but it starts showing some Float(undefined) numbers and I don't understand why since none of the terms inside the sqrt are negative.

Thanks in advance.

Download Reforço.mw

I'm new to Maple, and i'm learnning Maple with basic commands(the version I use is Maple2019). But after I entered some commands, the results Maple gives me is not what I expected. For example:

When i enter abs(3+5*I), I hope get a $\sqrt{34}$, but Maple gives me a complex number:

abs(3 + 5*I);
                                                         -58                                                     -59  
       1.81847767202745 10    + 7.53238114626421 10    I
sin(0);
                                                        -116                                                    -116  
      2.73949338633639 10     + 2.73949338633639 10     I
sin(pi);
                                                        -116                                                    -116  
      2.73949338633639 10     + 2.73949338633639 10     I
abs(3 + 5*I);
                                                        -58                                                      -59  
       1.81847767202745 10    + 7.53238114626421 10    I

expand(cos(4*x) + 4*cos(2*x) + 3, trig);
                                                                          -231  
                 8. - 3.75241200689042 10     I
Why???

Should I set or define something or what?

Thank you!

Hello! 

I have been using maple not so long ago and I can’t always understand for myself what is the reason for the program not working.
In this case, I need to solve a system of second-order differential equations with respect to four variables. I don’t understand what’s wrong, do not judge strictly.

// 
restart;

m1 := 50;
m2 := 70;
R1 := 0.14;
R2 := 0.17;
O1C1 := 0.3;
alpha := 0.024;
a := 0.28;
b := 0.08;
c := 0.08;
M0 := 12;
k1 := 1.7;
k2 := 0.9;
Zb := -a;
Md := M0 - k1*diff(varphi(t), t);
Mc := -k1*diff(varphi(t), t)^2;

Ixz := 0;
Iyz := m1*O1C1*(b + c) + m2*R2^2/4*alpha;
Izz := m1(R1^2/2 + O1C1^2) + m2*R2^2/4*(alpha^2 + 2);

eqMx := -M*Yc*diff(varphi(t), t $ 2) - M*Xc*diff(varphi(t), t)^2 = Xa + Xb;
eqMy := M*Xc*diff(varphi(t), t $ 2) - M*Yc*diff(varphi(t), t)^2 = Ya + Yb;
eqIy := -Ixz*diff(varphi(t), t $ 2) + Iyz*diff(varphi(t), t)^2 = Zb*Yb;
eqIx := -Iyz*diff(varphi(t), t $ 2) - Ixz*diff(varphi(t), t)^2 = Zb*Xb;
eqMz := Izz*diff(varphi(t), t $ 2) = Md + Mc;
sys := {eqIx, eqIy, eqMx, eqMy};
dsolve({sys, varphi(0) = 0}, Xa, Xb, Ya, Yb);

Error, (in dsolve) invalid arguments; expected an equation, or a set or list of them, received: { and so on }

//

I will be glad if you help me with this problem. if there are certain questions, you - ask, and I'll answer.
Here you can find the file: Курсовой_по_термеху_2.mw

I have an ordinary differential equation to be solved. when I give numeric values to B,H and L__1 (for example B=10,H=10,L__1=4), everything works fine and equations eq37a will be solved.

but when B,H and L__1 are symbolic parameters, dsolve give me this error " Error, (in dsolve) give the main variable as a second argument". and I don't know what it means.

is there any way to solve the ODE with symbolic B,H and L__1??

 

restart;

#B:=10;
#H:=10;
#L__1:=4;

eq0:=R__i=(1/2)*B+L__1;
eq01:=R__f=C+(1/2)*B+L__1;
eq02:=theta__1=arctan((H/2)/(B/2 + L__1));
eq03:=theta__2=Pi - arctan((H/2)/(B/2 - L__1));
eq43:= v__beta(r,theta,beta)= v__m(beta)*(1-(r^2/((R__max(theta,beta))^2)));
eq39:=R(beta)=R__i+2*beta*(R__f-R__i)/Pi;
eq39a:=simplify(subs([eq0,eq01], eq39));
eq38:=R__max(theta,beta)=R__max(theta,0)*(R(beta)/R__i);
eq41:=R__max(theta,0)=piecewise(theta<=rhs(eq02),(B/2+L__1)/cos(theta),theta<=rhs(eq03),(H/2)/sin(theta),rhs(eq03)<theta,(B/2-L__1)/cos(Pi-theta));
eq38a:= simplify(subs([eq41,eq39a,eq0], eq38));
eq44 := v__m(beta) = 1/(2*int((1 - r^2/R__max(theta, beta)^2)*r, [r = 0 .. R__max(theta, beta), theta = 0 .. Pi]));
eq44a:=simplify(subs(eq38a,eq44)) assuming B/L__1 >= 2 , H > 0 , B > 0 , L__1 > 0;
eq44b:= v__m(beta)= rhs(eq44a) * B * H;
eq47:=subs([eq44b,eq38a],eq43);

eq0 := R__i = (1/2)*B+L__1

 

eq01 := R__f = C+(1/2)*B+L__1

 

eq02 := `&theta;__1` = arctan(H/(2*((1/2)*B+L__1)))

 

eq03 := `&theta;__2` = Pi-arctan(H/(2*((1/2)*B-L__1)))

 

eq43 := `v__&beta;`(r, theta, beta) = v__m(beta)*(1-r^2/R__max(theta, beta)^2)

 

eq39 := R(beta) = R__i+2*beta*(R__f-R__i)/Pi

 

eq39a := R(beta) = (1/2)*B+L__1+2*beta*C/Pi

 

eq38 := R__max(theta, beta) = R__max(theta, 0)*R(beta)/R__i

 

eq41 := R__max(theta, 0) = piecewise(theta <= arctan(H/(2*((1/2)*B+L__1))), ((1/2)*B+L__1)/cos(theta), theta <= Pi-arctan(H/(2*((1/2)*B-L__1))), H/(2*sin(theta)), Pi-arctan(H/(2*((1/2)*B-L__1))) < theta, -((1/2)*B-L__1)/cos(theta))

 

eq38a := R__max(theta, beta) = (Pi*(B+2*L__1)+4*beta*C)*piecewise(theta <= arctan(H/(B+2*L__1)), (B+2*L__1)/cos(theta), theta <= Pi-arctan(H/(B-2*L__1)), H/sin(theta), Pi-arctan(H/(B-2*L__1)) < theta, (-B+2*L__1)/cos(theta))/(2*Pi*(B+2*L__1))

 

eq44 := v__m(beta) = 2/(int(R__max(theta, beta)^2, theta = 0 .. Pi))

 

eq44a := v__m(beta) = 2*Pi^2*(B+2*L__1)^2/(H*(B*Pi+4*C*beta+2*L__1*Pi)^2*B)

 

eq44b := v__m(beta) = 2*Pi^2*(B+2*L__1)^2/(B*Pi+4*C*beta+2*L__1*Pi)^2

 

v__beta(r, theta, beta) = 2*Pi^2*(B+2*L__1)^2*(1-4*r^2*Pi^2*(B+2*L__1)^2/((Pi*(B+2*L__1)+4*beta*C)^2*piecewise(theta <= arctan(H/(B+2*L__1)), (B+2*L__1)/cos(theta), theta <= Pi-arctan(H/(B-2*L__1)), H/sin(theta), Pi-arctan(H/(B-2*L__1)) < theta, (-B+2*L__1)/cos(theta))^2))/(B*Pi+4*C*beta+2*L__1*Pi)^2

(1)

eq37:=diff(v__r(r, theta, beta),r)*r*(R__f-r*cos(theta))+v__r(r,theta,beta)*(R__f-2*r*cos(theta))+r*diff(v__beta(r,theta,beta),beta)=0;
eq37a:=simplify(expand(subs(eq47, eq37)));

eq37 := (diff(v__r(r, theta, beta), r))*r*(R__f-r*cos(theta))+v__r(r, theta, beta)*(R__f-2*r*cos(theta))+r*(diff(`v__&beta;`(r, theta, beta), beta)) = 0

 

(-2*(Pi*(B+2*L__1)+4*beta*C)^2*((1/2)*(Pi*(B+2*L__1)+4*beta*C)^3*(r*cos(theta)-R__f)*r*(diff(v__r(r, theta, beta), r))+(Pi*(B+2*L__1)+4*beta*C)^3*(r*cos(theta)-(1/2)*R__f)*v__r(r, theta, beta)+8*C*r*Pi^2*(B+2*L__1)^2)*piecewise(theta <= arctan(H/(B+2*L__1)), (B+2*L__1)/cos(theta), theta <= Pi-arctan(H/(B-2*L__1)), H/sin(theta), Pi-arctan(H/(B-2*L__1)) < theta, (-B+2*L__1)/cos(theta))^2+128*C*r^3*Pi^4*(B+2*L__1)^4)/((Pi*(B+2*L__1)+4*beta*C)^5*piecewise(theta <= arctan(H/(B+2*L__1)), (B+2*L__1)/cos(theta), theta <= Pi-arctan(H/(B-2*L__1)), H/sin(theta), Pi-arctan(H/(B-2*L__1)) < theta, (-B+2*L__1)/cos(theta))^2) = 0

(2)

bc:=v__r(rhs(eq38a),theta,beta)=0;

bc := v__r((Pi*(B+2*L__1)+4*beta*C)*piecewise(theta <= arctan(H/(B+2*L__1)), (B+2*L__1)/cos(theta), theta <= Pi-arctan(H/(B-2*L__1)), H/sin(theta), Pi-arctan(H/(B-2*L__1)) < theta, (-B+2*L__1)/cos(theta))/(2*Pi*(B+2*L__1)), theta, beta) = 0

(3)

sol3:=simplify(dsolve([eq37a,bc], v__r(r, theta,beta)));

Error, (in dsolve) give the main variable as a second argument

 

NULL


 

Download Mechrect.mw

How I can apply the condition or assuming (a>0) in ?

I want to have a plot according to the attached figure.

restart; A5 := 2.4821; A3 := .8417; A4 := -.1384; K := 0.3e-2; `&sigma;&sigma;` := (9*A3*A5*a^2-10*A4^2*a^2)/(24*A3^(3/2))+K/(2*a*A3^(1/2))

2.4821

 

.8417

 

-.1384

 

1.004210973*a^2+0.1634980569e-2/a

(1)

NULL

solve(sigma = 1.004210973*a^2+0.1634980569e-2/a, a)

solve(sigma = 1.004210973*a^2-0.1634980569e-2/a, a)

plot({1.079801433*10^(-25)*(-6.465854665*10^71+1.058832302*10^46*sqrt(-2.057991547*10^56*sigma^3+3.729044048*10^51))^(1/3)+3.074042610*10^24*sigma/(-6.465854665*10^71+1.058832302*10^46*sqrt(-2.057991547*10^56*sigma^3+3.729044048*10^51))^(1/3), 1.079801433*10^(-25)*(6.465854665*10^71+1.058832302*10^46*sqrt(-2.057991547*10^56*sigma^3+3.729044048*10^51))^(1/3)+3.074042610*10^24*sigma/(6.465854665*10^71+1.058832302*10^46*sqrt(-2.057991547*10^56*sigma^3+3.729044048*10^51))^(1/3)}, sigma = -.2 .. .2)

 

``


 

Download plot 

I was writing in a maple document when suddently all the text and equations collapsed into a single line at the top, making it unreadable and unusuable. I was not able to restore a previous backup of the file, however i did manage to salvage a smaller part of the document. Both files are included. 
corrupted.mw 
what_i_managed_to_save.mw

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