535 Reputation

10 Badges

10 years, 173 days

Social Networks and Content at

Seldom to ask question after retired math hobby Just waiting for beauty who born in 1994 And waited for her email to What is the difference in ownership among different universe?

MaplePrimes Activity

These are questions asked by ComputerUser

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:
 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)):
end if:
return R:
end proc:
coeff(p1, x, degree(p1, x));
coeff(p2, x, degree(p2, x));

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?
FlessThanG := proc(Fparam, Gparam, PRing)
F := Fparam:
G := Gparam:
if leader(F,PRing) < leader(G,PRing) or (leader(F,PRing) = leader(G,PRing) and degree(F, leader(F,PRing)) < degree(G, leader(G,PRing))) then
 return True:
 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:
thetax := leader(G, PRing);
while FlessThanG(R, G, PRing) or FlessThanG(G, R, PRing) do
theta := leader(R, PRing);
R := prem(R, thetaG, theta)
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?
i had defined constant
but got error
Error, (in DifferentialAlgebra:-Tools:-LeadingDerivative) unknown symbol (approx. error location: [m*x[2 --> ] <-- +r*x])


matrix([[1,0],[0,1]]) * matrix[[y],[y']]
= a system 


how to get back matrix([[1,0],[0,1]]) from this system in general method if the system is very large?

Is there a function to convert recurrence equation to a system of equations?

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

How to remove all punctuation marks in a string read from a text file 

and then store in a list of words according to the ordering of the original text?

First 8 9 10 11 12 13 14 Last Page 10 of 141