Hi MaplePrimes,

I'm trying to explore the polynomial r = n^2+n+39.  where n is an integer

I want restrictions on n such that r will factor into two trinomials.

Here is how far I got - 

prime_poly_39_explore.mw

The 'has' function may be helpful.

Any help is appreciated.

Regards,

Matt

I believe this is a bug:

 
(((Q(a)^3)^(5/4))^(15/7))^(6/8);
subsindets(%, anything^rational, proc(x) if type(x, specfunc(anything, Q)^rational) then 'Q(x)' else 'x' fi end)<>
subsindets(%, specfunc(anything, Q)^rational, Q);

Why am I not able to use my MaplePrimes login credentials to login into MapleCloud?

Hi!

I am very interested in using the "phc.module", which is a module to work with "polynomial homotopy continuation" method. Please, see this paper      

I have downloaded the following files: [copied without permission, deleted by moderator]

Then, I open (as an "ordinary" maple worksheet) the file "phc_savelib.maple" and execute it, but it seems that I can not use their functions and procedures because it returns errors. 

For instance, follwing the attached PDF,  in the phc_savelib.maple file, define the polynomial system:

T := makeSystem([x, y], [], [x^2+y^2-1, x^3+y^3-1])

and try to solve the above system 

sols := solve(T)

but returns the error 

Error, (in fopen) file or directory does not exist
 

Many thanks in advance for your help!

Hi all, I want to evaluate the integral G2. I am using the evalf command, but maple is unable to evaluate it. What am I missing here?

G2 := -.5*(int(Re(-(0.8823529412e-2*(-16.19435640-30.82287308*exp(-.2960360476-(1.*I)*theta)))*exp(.1480180238-(1.*I)*(.5*theta-0.6282080040e-1*ln(-1.*sin(-.3926990818+.5*theta)/sin(.3926990818+.5*theta))))*(-.5*cos(.3926990818+.5*theta)*sin(-.3926990818+.5*theta)+.5*sin(.3926990818+.5*theta)*cos(-.3926990818+.5*theta))/sqrt(-1.*sin(.3926990818+.5*theta)*sin(-.3926990818+.5*theta))-0.1764705882e-1*sqrt(-1.*sin(.3926990818+.5*theta)*sin(-.3926990818+.5*theta))*(1.017602550-3.872635115*exp(-.2960360476-(1.*I)*theta))*exp(.1480180238-(1.*I)*(.5*theta-0.6282080040e-1*ln(-1.*sin(-.3926990818+.5*theta)/sin(.3926990818+.5*theta))))-0.1764705882e-1*sqrt(-1.*sin(.3926990818+.5*theta)*sin(-.3926990818+.5*theta))*(-16.19435640-30.82287308*exp(-.2960360476-(1.*I)*theta))*(-0.6282080040e-1-(0.6282080040e-1*I)*(.5*cos(-.3926990818+.5*theta)/sin(.3926990818+.5*theta)+.5*sin(-.3926990818+.5*theta)*cos(.3926990818+.5*theta)/sin(.3926990818+.5*theta)^2)*sin(.3926990818+.5*theta)/sin(-.3926990818+.5*theta))*exp(.1480180238-(1.*I)*(.5*theta-0.6282080040e-1*ln(-1.*sin(-.3926990818+.5*theta)/sin(.3926990818+.5*theta)))))*(-.5-.5*cos(2.*theta))+.5*Im(-(0.8823529412e-2*(-16.19435640-30.82287308*exp(-.2960360476-(1.*I)*theta)))*exp(.1480180238-(1.*I)*(.5*theta-0.6282080040e-1*ln(-1.*sin(-.3926990818+.5*theta)/sin(.3926990818+.5*theta))))*(-.5*cos(.3926990818+.5*theta)*sin(-.3926990818+.5*theta)+.5*sin(.3926990818+.5*theta)*cos(-.3926990818+.5*theta))/sqrt(-1.*sin(.3926990818+.5*theta)*sin(-.3926990818+.5*theta))-0.1764705882e-1*sqrt(-1.*sin(.3926990818+.5*theta)*sin(-.3926990818+.5*theta))*(1.017602550-3.872635115*exp(-.2960360476-(1.*I)*theta))*exp(.1480180238-(1.*I)*(.5*theta-0.6282080040e-1*ln(-1.*sin(-.3926990818+.5*theta)/sin(.3926990818+.5*theta))))-0.1764705882e-1*sqrt(-1.*sin(.3926990818+.5*theta)*sin(-.3926990818+.5*theta))*(-16.19435640-30.82287308*exp(-.2960360476-(1.*I)*theta))*(-0.6282080040e-1-(0.6282080040e-1*I)*(.5*cos(-.3926990818+.5*theta)/sin(.3926990818+.5*theta)+.5*sin(-.3926990818+.5*theta)*cos(.3926990818+.5*theta)/sin(.3926990818+.5*theta)^2)*sin(.3926990818+.5*theta)/sin(-.3926990818+.5*theta))*exp(.1480180238-(1.*I)*(.5*theta-0.6282080040e-1*ln(-1.*sin(-.3926990818+.5*theta)/sin(.3926990818+.5*theta)))))*sin(2.*theta), theta = 0. .. .7853981635))

I'm trying to solve this to set of equations :

EQ1:=-1958143.922*k*wr+2468.8339*k^3*wr-0.9481118254e16*k^2-114000.8376*k^4:

EQ2 :=-1186578.220*R*k^2*wr-312683.0293*k^5-288960.9621*k^3*R:

using a loop for different value of R in the range this range (wr=0..10,k=0..10)

eqns:={EQ1,EQ2}:
for i from 1 by 1 to 101 do R:=(i-1):S:=fsolve(eqns,{k, wr},{wr=0..10,k=0..10}):v(i):=(subs(S,(wr)));w(i):=(subs(S,(k)))end do:

but i get this instead :

Error, invalid input: subs received fsolve({-312683.0293*k^5, -1958143.922*k*wr+2468.8339*k^3*wr-0.9481118254e16*k^2-114000.8376*k^4}, {k, wr}, {k = 0 .. 10, wr = 0 .. 10}), which is not valid for its 1st argument

is there another way to solves this equations more easly .

Download SHAFEEG2.mwSHAFEEG2.mw

sdf.pdf,sdf.mw

Maple does not simplify the expression A*[sin(x)]^2+A*[cos(x)]^2=A, where A is any expression.

How can I make it do so? 

Thanks,

Maple 17 64-bit on Windows 8

Hi!

Let F(z) (with z complex) a given function. I want to compute F^n(z0), i.e. the composition of F with itself n-times, where z0 is a given point (complex).

Is correct the following procedure to compute F^k(z0)?

App := proc (k, z0) local z1, z2, j; z1 := z0; z2 := NULL; for j to k do z2 := F(z1); z1 := z2 end do; return z2 end proc

Many thanks in advance for your comments.

Hello!! Please help me,I need to solve a system of linear algebraic equations by running, and I solved the built-in command solve

restart;
with(plots):
f:=unapply(-x^2+1,x);
mu[1]:=unapply(1/(t^2+1),t);
mu[2]:=unapply(1/(t-5),t); 
g:=unapply(t^3-7*x,[t,x]);
l:=2; T:=3;
n:=10: m:=n: 
h:=evalf(l/n); 
tau:=evalf(T/m);
for k from 0 to n do 
x[k]:=h*k:
end do: 
for j from 0 to m do 
t[j]:=tau*j: 
end do:
ss:=evalf({seq(seq((y[k,j+1]-y[k,j])/tau=(y[k-1,j]-2*y[k,j]+y[k+1,j])/h^2+g(t[j],x[k]),k=1..n-1),j=0..m-1),seq(y[0,j]=mu[1](t[j]),j=1..m),seq(y[k,0]=f(x[k]),k=0..n),seq(y[n,j]=mu[2](t[j]),j=1..m)});
#s:=evalf(solve(ss,{seq(seq(y[k,j],k=0..n),j=0..m)}));

Good evening!!! I have a task to implement the task of Cauchy by the method of Milne, wrote the code, but did not understand it until the end, help to understand? what's wrong?
First calculate four "initial" values by the method of Runge-Kutta methods, then use the method of Milne, the Fact that two times running, perhaps extra?

restart;
with(plots):
a:=0; b:=1; eps:=evalf(10^(-3)):
f:=unapply(2*x*(x^2+y),x,y);
G:=simplify(dsolve({diff(y(x),x)=f(x,y(x)),y(a)=1}));                    
N:=15: h:=(b-a)/N:
for i from 0 to N do 
x[i]:=a+i*h: 
end do:
y[0]:=1;
s[0]:=1;
for i from 0 to 2 do 
t[1]:=evalf(h*f(x[i],y[i])):
t[2]:=evalf(h*f(x[i]+h/2,y[i]+t[1]/2)): 
t[3]:=evalf(h*f(x[i]+h/2,y[i]+t[2]/2)):
t[4]:=evalf(h*f(x[i]+h,y[i]+t[3])):
y[i+1]:=evalf(y[i]+(t[1]+2*t[2]+2*t[3]+t[4])/6):
q[1]:=evalf(h*f(x[i],s[i])):
q[2]:=evalf(h*f(x[i]+h/2,s[i]+q[1]/2)): 
q[3]:=evalf(h*f(x[i]+h/2,s[i]+q[2]/2)):
q[4]:=evalf(h*f(x[i]+h,s[i]+q[3])):
s[i+1]:=evalf(s[i]+(q[1]+2*q[2]+2*q[3]+q[4])/6):
end do;
for i from 3 to N-1 do 
y[i+1]:=evalf(y[i-3]+((4*h)/3)*(2*f(x[i],y[i])-f(x[i-1],y[i-1])+2*f(x[i-2],y[i-2]))):
s[i+1]:=evalf(s[i-1]+(h/3)*(f(x[i+1],y[i+1])+4*f(x[i],s[i])+f(x[i-1],s[i-1]))):
d[i+1]:=abs(y[i+1]-s[i+1])/29:
if abs(d[i+1]) < eps then y[i]:=y[i]:
else y[i]:=s[i];
end if: end do;
s1:=plot(rhs(G),x=a..b,color=yellow):
s2:=pointplot({seq([x[k],y[k]],k=0..N)}): 
display(s1,s2);

I want to write a procedure called Resistance which calculates and displays the equivalent resistance to three resistors R1, R2 and R3

If the resistances are connected in series then Rser = R1 + R2 + R3

If the resistances are connected in parallel then (R1 * R2 * R3) / (R1 * R2 + R1 * R3 + R2 * R3) and after that, I must write an algorithm which I will test this resistance but it does not work please help me
 

Download RESISTANCE.mw

Good day.

I have a problem with the numerical approximation of incomplete elliptic integrals of the first kind in the case when the argument and the modulus are complex numbers. 

Let's consider an incomplete elliptic integral of the first kind EllipticF((a+I*b)*x, c+I*d), where a,b,c,d are arbitrary real numbers and x is very large number. Here is the code:

restart;
R0 := EllipticF((a+I*b)*x, c+I*d);
with(MultiSeries, series):
R1 := series(R0, x = infinity, 2);
a := .5; b := 1.75; c := 10; d := 12.5; x := 10^6;
evalf(R0); evalf(R1);

Below you can see that answers are different

.1680611942+.2058775337*I
-0.4563467782e-1-.3592094173*I+O(1/1000000000000000000)

While the same code for an incomplete elliptic integral of the second kind gives the correct approximation:

restart;
R00 := EllipticE((a+I*b)*x, c+I*d);
R11 := series(R00, x = infinity, 2);
a := .5; b := 1.75; c := 10; d := 12.5; x := 10^6;
evalf(R00); evalf(R11);
-1.687498740*10^7+2.374999011*10^7*I
-1.687501260*10^7+2.375000989*10^7*I+O(1/1000000)

What is the difference?
 

I want to visualize data provided by the Maximize command. The output I get is of the following form (example):

 [.358700275060090779, [p[0] = .192413186080606, p[1] = 0.906594292940704e-1, p[2] = 0.677108912885780e-1, p[3] = 0.609551830556988e-1, p[4] = 0.589744573790909e-1, p[5] = 0.585737058072817e-1, p[6] = 0.589744573787748e-1, p[7] = 0.609551830550955e-1, p[8] = 0.677108912877626e-1, p[9] = 0.906594292931833e-1, p[10] = .192413186079858]]
I want to plot the sequence p[0], ..., p[10] with the command LineChart (for example).

My question is: How to automatically "clean up" output as above so I can feed it to LineChart?