## Why does my procedure not work?...

with(RegularChains);
R := PolynomialRing([x, y, z]);
p1 := x^2+5-2*x*z;
p2 := z^3*y+x*y^2;
p3 := -8*z^3+3*y^2;
F := [p1, p2, p3];
MainVariable(p1, PolynomialRing([x, y, z]));
MainVariable(p1, PolynomialRing([z, y, x]));
prem(p1, p2, x);
prem(p2, p1, z);
prem(p3, p2, y);
premcustom := proc(Fparam,Gparam, xparam)
local R, G, F, lcg, lcr, dr, dg:
R := Fparam:
G := Gparam:
F := Fparam:
if degree(G,xparam) = 0 then
print("return 0"):
return 0:
elif degree(F, xparam) < degree(G, xparam) then
print("return R"):
return R:
else
lcg := coeff(G, xparam, degree(G, xparam)):
dg := degree(G, xparam):
while degree(R, xparam) > degree(G, xparam) do
lcr := coeff(R, xparam, degree(R, xparam)):
dr := degree(R, xparam):
R := lcg * R - lcr * G * (x^(dr - dg)):
od:
end if:
return R:
end proc:
coeff(p1, x, degree(p1, x));
coeff(p2, x, degree(p2, x));
prem(p1,p2,x);
prem(p2,p1,z);

premcustom(p1,p2,x);
premcustom(p2,p1,z);

why premcustom looping?

is this coeff(p1, x, degree(p1, x)); wrong ?

should this to get real coefficient in number instead of variable and how?

is there equivalent function as dprem?

with(diffalg):with(diffalg):
FlessThanG := proc(Fparam, Gparam, PRing)
F := Fparam:
G := Gparam:
return True:
else
return False:
end if:
end proc:
dprem := proc(Fparam, Gparam, x, PRing)
local R, theta, thetax, thetaG, F, G;
F := Fparam:
G := Gparam:
R := F:
while FlessThanG(R, G, PRing) or FlessThanG(G, R, PRing) do
R := prem(R, thetaG, theta)
od:
return R:
end proc:
R := differential_ring(ranking = [[x,y,r]], derivations = [t], field_of_constants=[m,l], notation = diff):
p1 := m*x[2] + r*x;
p2 := m*y[2] + r*y - g;
p3 := x^2 + y^2 - l^2;
dprem(p1, p3, x, R);

is x[2] = diff(x,t\$2) in diffalg ?

if not how to write in this way?

but got error

Error, (in DifferentialAlgebra:-Tools:-LeadingDerivative) unknown symbol (approx. error location: [m*x[2 --> ] <-- +r*x])

## How to find recurrence relation for this?...

https://math.stackexchange.com/questions/301068/how-do-you-find-a-corresponding-recurrence-relation-for-some-random-algorithm/301709

according to this link, how to parse or walk through the algorithm in maple to generate recurrence relation formula?

## how to convert a function and differential system ...

how to convert a function to transition matrix?

how to convert a differential system to transition matrix?

## Saveplot function not refresh in for loop call...

I search saveplot and sleep function here

i had kept close filename function and move plot setup default to first line

but thread no sleep in maple 12

then I remove sleep and can save image file

but after I call it in a function and run a for loop for this function

the file is not updated after sleep 3 seconds

how to run a for loop call it and it can refresh

## Lyapunov function ...

Dear all

Is there a nice idea to determine the Lyapunov function of the following system

Lyapunov_function.mw

Some parameters used in the code:

b fixed parameter

a any parameter in R

## How to fill in missing data with statistics?...

If I know the direction of up and down

how to control normal distribution to fill in missing data to the direction I want in maple?

just like fill in missing pixel in bitmap file.

## system of ODEs: stabilizing feedback...

Hi all;

I need to compute the stabilizing feedback for the system of nonlinear ODEs

stabilizing_Feedback.mw

## Which Bernstein has these result?...

Second terms coefficient = 2/3*x when (....)^2

9/16*x^2 when (...)^3

64/125*x^3 when (...)^4

625/1296*x^4

Which Bernstein has these result?

Which limit function of x^n = (n^(n-1))/((n+1)^(n-1))*x^(n-1)?

how to find and calculate?

## Variable disappear after read file and create thre...

Variable disappear after read file and then pass parameter to create thread

## How i can convert this mathematic code to maple...

How i convert the following mathematica code to Maple

f1[t^m_] := Gamma [m + 1] t^(m - a[t]) /Gamma[m + 1 + a[t]];
f1[t] := Gamma [2] t^(1 - a[t]) /Gamma[2 + a[t]];

f1[p_Plus] := Map[f1, p]
f1[c_*f_] := c*f1[f] /; FreeQ[c, t]
f1[c_] := 0 /; FreeQ[c, t]

f1[x^2*t^2 + t + x]

gives

t^(1 - a[t])/Gamma[2 + a[t]] + (2 t^(2 - a[t]) x^2)/Gamma[3 + a[t]]

## How to plot y=0?...

Plot([x^2, subs(x=0, 2*x)], axis[1]=[color=white]);

can not find the y=0 this red line

how to plot y=x^2 and x = 0 on the same graph to show the slope at x=0 ?

## How to derive to limit definition?...

How to derive from n*x^(n-1) to limit definition ?

## How to proof exp(x) is transcendental function wit...

How to proof exp(x) is transcendental function without using calculus?

## How to convert ODE to PDE?...

How to convert diff(f(t),t) + diff(g(t),t)

to diff(t(f,g), f)+ diff(t(f,g), g)

?