## Parameters with values in the Maple textplot...

Dear Maple experts, I want to write text in a specific location within a Maple plot like p<c. To do that, I use 'plots:-textplot' as follows:

plots:-textplot([[0.1, 0.80, p < c, color = black]], font = [times, 11], rotation = 'horizontal');

The issue is that in my code, 'p' and 'c' are parameters with specific values. Therefore,  in my plot, their values appear instead of p<c. Even if I use 'p<c' or "p<c" it does not work.

Would you please guide me on how to solve the issue?

## Translate Mathematica-Expression to Maple-Code...

I have tried to translate the Mathematica-Code of OEIS (A219954):

with MmaTranslator. In the translator occurs an error message with the IF-Statement ...

I will be happy to have this in Maple. I am interested in the digitCount in the above Code.

Sequence is:

 Thanks for help :)

## Need to Solve System of ODE Using RK-4...

Hello Everyone;

I need help to solve the following system using rk-4 method

restart;
NULL;
NULL;
C := 1.0;
gK := 36.0;
gNa := 120.0;
gL := 0.3;
VK := -77.0;
VNa := 50.0;
VL := -54.0;
III := 20;
alpha_n := 0.01*(v(t) + 55.0)/(1 - exp(-1.0/10.0*v(t) - 11.0/2.0));
beta_n := 0.125*exp((-v(t))/80.0 + (-1)*13.0/16.0);
alpha_m := 0.1*(v(t) + 40.0)/(1 - exp(-1.0/10.0*v(t) - 4.0));
beta_m := 4.0*exp(-1.0/18.0*v(t) - 65.0/18.0);
alpha_h := 0.07*exp((-1)*(v(t) + 65.0)/20.0);
beta_h := 1/(1.0 + exp((-v(t) + 35.0)/10.0));

dsys1 := {diff(h(t), t) = alpha_h*(1 - h(t)) - beta_h*h(t), diff(m(t), t) = alpha_m*(1 - m(t)) - beta_m*m(t), diff(n(t), t) = alpha_n*(1 - n(t)) - beta_n(t), diff(v(t), t) = III - gK*n(t)^4*(v(t) - VK) - gNa*m(t)^3*h(t)*(v(t) - VNa) - gL*(v(t) - VL), h(0) = 0.9996937394, m(0) = 0.02890553447, n(0) = 0.2445865495, v(0) = -70};

## Point plot for system of nonlinear equations...

Dear Maple experts,

I have a system of several nonlinear equaitons. My code can solve it for a given parameter. But when I want to plot it, it takes too much time with no results. So, I decided to plot it for several given points. I get the answer for the points individually, but I don't know how to apply this to 'plot' command. Would you please help?

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Besdies, it seems for some points there is no feasible solution. So, there is no need to have plot for them.

I attach the code. Thank you so much!

## Analytical Solution of Nonlinear ODE ...

Hello Everyone;

Can anybody help me to solve the analytical solution of the following ODE?
AAS := C*diff(y(t), t) + (-B0*y(t)^3 - B1*y(t)^2 - B2*y(t) - B3);y[0] := 1

C,B0,B1,B2 are constants.

## Plot line symbols disappear in legend ...

Dear Maple experts,

I am running a Maple code with several lines/ curves in a plot.

For two of the curves, I use style=pointline. But in the legend the symbols on the lines are not shown. Can you advise how we can make them appear?

I have attached the file. Thank you so much!

## Need to Solve Nonlinear ODE...

Hello Everyone;

I need to solve the following nonlinear ODE

C*diff(y(x), x) + (-B0*y(x)^3 - B1*y(x)^2 - B2*y(x) - B3) = 0, y(0)=B4

where B0,B1,B2,B3 and B4 are constants. I am trying in Maple 2021, but receiving solution in the form of integral. Is that any other ways that I will be able exact solution. Maple sheet is atatched. I am waiting for your kind respose.

Thanks

Question1.mw

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 Methods for first order ODEs:
 --- Trying classification methods ---
 trying 1st order linear
 trying Bernoulli
 trying separable
 <- separable successful
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 Methods for first order ODEs:
 --- Trying classification methods ---
 trying 1st order linear
 trying Bernoulli
 trying separable
 <- separable successful
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## System of two equations and evaluate...

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 > WhyNot3 := proc (alpha, delta) if not [alpha, delta]::(list(numeric)) then return ('procname')(args) end if; FirmModelHmax(alpha, .2, delta)[3] end proc: pltHmax1 := plot(   [seq(WhyNot3(alpha, delta),delta=0.1..0.5,0.2)]     , alpha=0..2/(2 + 0.2*(1 - sqrt((c - s)/(v - s))))        , linestyle=[dot,dashdot,dash]       , legend=[seq('delta'=delta,delta=0.1..0.5,0.2)]       , legendstyle=[location=left]       , labels=["alpha","Firm profit"]       , labeldirections =["horizontal", "vertical"]     , legendstyle=[location=bottom] ): display(pltHmax1)
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## Unable To Type In Maple, No Cursor...

I am currently unable to type in maple 2021, there is no cursor, nothing shows up when I type etc. I am also unable to save files. I went into document mode, nothing. Some of the dialogs don't show up. Where does maple save documents and how do I change that setting? That might be my problem. Furthermore, there are no tabs visable, like I can't access any documents I open.

## Differentiate three regions with implicitplot and/...

Dear Maple Expeets, In the attached Maple file, I have three procedures that are run smoothly. I am trying to compare outputs from each procedure to see which one if larger than the others. For changes on two parameters (alpha and delta), I used implicitplot and inequal commands to identify each region by a specific color. But the outcome is not reasonable. Would you please help with this? Thanks in advance!

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the final plot does not look reasonable. Would you please guide me?

## Two dimensional simple random walk to factorize...

by: Maple 2021

aRandStep2D := proc(X0, Y0, dx, dy)
local X, Y, P, R;
P := Array(1 .. 2);
R := rand(1 .. 8)();
if R = 1 then X := X0 - dx; Y := Y0 + dy; end if;
if R = 2 then X := X0; Y := Y0 + dy; end if;
if R = 3 then X := X0 + dx; Y := Y0 + dy; end if;
if R = 4 then X := X0 - dx; Y := Y0; end if;
if R = 5 then X := X0 + dx; Y := Y0; end if;
if R = 6 then X := X0 - dx; Y := Y0 - dy; end if;
if R = 7 then X := X0; Y := Y0 - dy; end if;
if R = 8 then X := X0 + dx; Y := Y0 - dy; end if;
P[1] := X; P[2] := Y;
return P;
end proc

SetStart := proc(b)
local alpha, R, P;
P := Array(1 .. 2);
alpha := rand(1 .. b)();
P[1] := alpha*b;
P[2] := alpha*b;
return P;
end proc

RandomFactTpq := proc(N, pb, dx, dy)
local alpha, X, Y, f, P, counter, B, n, T;
P := Array(1 .. 2);
counter := 0; f := 1;
B := floor(evalf(sqrt(N))); #Set maximal searching steps
T := floor(evalf(sqrt(N))); #For SetStart's use
P := SetStart(T);
X := P[1]; Y := P[2];
while f = 1 and counter < B do  #loop
n := pb - X - Y;
f := gcd(N, n);
if f > 1then break; end if;
P := aRandStep2D(X, Y, dx, dy); #A random move
X := P[1]; Y := P[2];
if X < 1 or Y < 1 or N - pb - 1 < X or X <= Y then
P := SetStart(T);       # Restart when out of borders
X := P[1]; Y := P[2];
end if;
counter := counter + 1;    #Counting the searched steps
end do;
if  f>1  then print(Find at point (X, Y), found divisor = f, searching steps = counter);
else print(This*time*finds*no*result, test*again!); end if;
end proc

## Numerical solution, Produce a graph with various v...

How can I produce a graph with various values for parameters? I also attached a sample of my Maple code.

`restart`

```with(plots); with(plottools); with(DEtools);```

`eqn1 := diff(V(t), t) = pi*p - (alpha + mu)*V(t), V(0) = ic1`

`eqn2 := diff(S(t), t) = alpha*V(t) + (1 - p)*pi - beta*S(t)*In(t)/N - mu*S(t), S(0) = ic2`

`eqn3 := diff(In(t), t) = beta*S(t)*In(t)/N - (mu + delta + gamma)*In(t), In(0) = ic3`

`eqn4 := diff(R(t), t) = gamma*In(t) - mu*R(t), R(0) = ic4`

```pi := 487845; p := 0.948; alpha := 0.054; beta := 0.955; mu := 0.005; delta := 0.03; localgamma := 0.935; ic1 := 484465; ic2 := 31999760; ic3 := 26305; ics4 := 12470; dsol := dsolve([eqn1, eqn2, eqn3, eqn4], numeric);```

`odeplot(dsol, [[t, V(t), color = plum], [t, S(t), color = blue], [t, In(t), color = cyan], [t, R(t), color = green]], t = 0 .. 1000, view = [0 .. 1000, 0 .. 300000000], thickness = 3)`

Let's say I want to produce a graph for eqn1 with various values of parameter p: p = 0.2, p = 0.5, p = 0.7, p = 0.8. How should I produce it?

## Plot the value of determinant vs omega...

I have created a several matrices for my analysis. I want to plot the determinant value of matrix vs the omega. The matrix that should be plotted is named as FINAL. I am not able to do that due to large value of matrix determinant. How to simplify the matrix and get  plot.

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