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I've conducted DuckDuckGo searches for "Sturm-Liouville sagemath" and received no usable results, and as a result I am here to ask, how can one solve Sturm-Liouville problems with SageMath? I know how to do so numerically with Julia, GNU Octave and Scilab, using matrices, but is there any way to solve at least some of them analytically in SageMath (e.g. $\frac{d^2 y}{dx^2}-xy = \lambda y$ has solutions $y_n=C\cdot \textit{Ai}(x+\lambda_n)$, where $\lambda_n$ are the zeros of the Airy $\it{Ai}(x)$ function)? Failing this, is there a way to numerically solve them in SageMath?

I've conducted DuckDuckGo searches for "Sturm-Liouville sagemath" and received no usable results, and as a result I am here to ask, how can one solve Sturm-Liouville problems with SageMath? I know how to do so numerically with Julia, GNU Octave and Scilab, using matrices, but is there any way to solve at least some of them analytically in SageMath (e.g. $\frac{d^2 y}{dx^2}-xy = \lambda y$ has solutions $y_n=C\cdot \textit{Ai}(x+\lambda_n)$, where $\lambda_n$ are the zeros of the Airy $\it{Ai}(x)$ $\textit{Ai}(x)$ function)? Failing this, is there a way to numerically solve them in SageMath?

I've conducted DuckDuckGo searches for "Sturm-Liouville sagemath" and received no usable results, and as a result I am here to ask, how can one solve Sturm-Liouville problems with SageMath? I know how to do so numerically with Julia, GNU Octave and Scilab, using matrices, but is there any way to solve at least some of them analytically in SageMath (e.g. $\frac{d^2 y}{dx^2}-xy = \lambda y$ has solutions $y_n=C\cdot \textit{Ai}(x+\lambda_n)$, where $\lambda_n$ are the zeros of the Airy $\textit{Ai}(x)$ function)? Failing this, is there a way to numerically solve them in SageMath?SageMath (without resorting to their interfaces with the languages I just mentioned)?

I've conducted DuckDuckGo searches for "Sturm-Liouville sagemath" and received no usable results, and as a result I am here to ask, how can one solve Sturm-Liouville problems with SageMath? I know how to do so numerically with Julia, GNU Octave and Scilab, using matrices, but is there any way to solve at least some of them analytically in SageMath (e.g. $\frac{d^2 y}{dx^2}-xy = \lambda y$ has solutions $y_n=C\cdot \textit{Ai}(x+\lambda_n)$, where $\lambda_n$ are the zeros of the Airy $\textit{Ai}(x)$ function)? Failing this, is there a way to numerically solve them in SageMath (without resorting to their its interfaces with the languages I just mentioned)?

I've conducted DuckDuckGo searches for "Sturm-Liouville sagemath" and received no usable results, and as a result I am here to ask, how can one solve Sturm-Liouville problems with SageMath? I know how to do so numerically with Julia, GNU Octave and Scilab, using matrices, but is there any way to solve at least some of them analytically in SageMath (e.g. $\frac{d^2 y}{dx^2}-xy = \lambda y$ has solutions $y_n=C\cdot \textit{Ai}(x+\lambda_n)$, where $\lambda_n$ are the zeros of the Airy $\textit{Ai}(x)$ function)? function, if $y(0)=y(\infty)=0$)? Failing this, is there a way to numerically solve them in SageMath (without resorting to its interfaces with the languages I just mentioned)?

# Standard values are for transformation x=(y-L)/(y+L), y in 0, inf
# *lin are for x=2/L*y-1 (linear transformation)
clear all
format long e;
N=5000;
perc=0.266
Nfrag=round(perc*N);
n=0:N;
# 75 at N=1k; 162 for N=3k; 225 for N=5k;
L=226;
t=pi+n'*pi/N;
x=cos(t);
y=L*(cot(t/2)).^2;
ysub=y(2:N);
ylintrans = L/2*(x+1);
# Chebyshev polys of the first kind
T         = cos(t*n);
# Now for arrays that do not include the endpoints
xsub      = x(2:N);
Tsub      = T(2:N,:);
Usub      = diag(1./sqrt(1-xsub.^2))*sin(acos(xsub)*n);
dTsub     = Usub*diag(n);
dT        = [-(n.^2).*(-1).^(n); dTsub ; (n).^2];
dTL       = diag(2*L./((y+L).^2))*dT;
dTlin     = 2/L*dT;
D1        = dTL/T;
D1lin     = dTlin/T;
D2        = D1^2;
D2lin     = D1lin^2;
H         = D2-diag(y);
Hlin      = D2lin-diag(ylintrans);
H         = H(2:N,2:N);
Hlin      = Hlin(2:N,2:N);
[Y, Lam]  = eig(H);
[Ylin, Lamlin] = eig(Hlin);
Lam       = diag(Lam);
Lamlin    = diag(Lamlin);
[Lam, IX] = sort(Lam, 'ascend');
[Lamlin, IXlin] = sort(Lamlin, 'ascend');
Y         = Y(:,IX);
Ylin      = Ylin(:,IXlin);
aizerochk = abs(airy(0,Lam));
aizerochklin = abs(airy(0,Lamlin));
L
errrms    = sqrt(aizerochk(1:Nfrag)'*aizerochk(1:Nfrag)/(Nfrag+1))
errrmslin    = sqrt(aizerochklin(1:Nfrag)'*aizerochklin(1:Nfrag)/(Nfrag+1))
ain=quad("airynorm",0,100);
figure(1)
plot(ysub(1:3*N/5), Y(1:3*N/5,1));
figure(2)
plot(ysub(1:3*N/5), Y(1:3*N/5,2));
figure(3)
plot(ysub(1:3*N/5), Y(1:3*N/5,Nfrag));

I've conducted DuckDuckGo searches for "Sturm-Liouville sagemath" and received no usable results, and as a result I am here to ask, how can one solve Sturm-Liouville problems with SageMath? I know how to do so numerically with Julia, GNU Octave and Scilab, using matrices, but is there any way to solve at least some of them analytically in SageMath (e.g. $\frac{d^2 y}{dx^2}-xy = \lambda y$ has solutions $y_n=C\cdot \textit{Ai}(x+\lambda_n)$, where $\lambda_n$ are the zeros of the Airy $\textit{Ai}(x)$ function, if $y(0)=y(\infty)=0$)? Failing this, is there a way to numerically solve them in SageMath (without resorting to its interfaces with the languages I just mentioned)?

OK, here's the code I use in GNU Octave to solve the aforementioned :SLE:

# Standard values are for transformation x=(y-L)/(y+L), y in 0, inf
# *lin are for x=2/L*y-1 (linear transformation)
clear all
format long e;
N=5000;
perc=0.266
Nfrag=round(perc*N);
n=0:N;
# 75 at N=1k; 162 for N=3k; 225 for N=5k;
L=226;
t=pi+n'*pi/N;
x=cos(t);
y=L*(cot(t/2)).^2;
ysub=y(2:N);
ylintrans = L/2*(x+1);
# Chebyshev polys of the first kind
T         = cos(t*n);
# Now for arrays that do not include the endpoints
xsub      = x(2:N);
Tsub      = T(2:N,:);
Usub      = diag(1./sqrt(1-xsub.^2))*sin(acos(xsub)*n);
dTsub     = Usub*diag(n);
dT        = [-(n.^2).*(-1).^(n); dTsub ; (n).^2];
dTL       = diag(2*L./((y+L).^2))*dT;
dTlin     = 2/L*dT;
D1        = dTL/T;
D1lin     = dTlin/T;
D2        = D1^2;
D2lin     = D1lin^2;
H         = D2-diag(y);
Hlin      = D2lin-diag(ylintrans);
H         = H(2:N,2:N);
Hlin      = Hlin(2:N,2:N);
[Y, Lam]  = eig(H);
[Ylin, Lamlin] = eig(Hlin);
Lam       = diag(Lam);
Lamlin    = diag(Lamlin);
[Lam, IX] = sort(Lam, 'ascend');
[Lamlin, IXlin] = sort(Lamlin, 'ascend');
Y         = Y(:,IX);
Ylin      = Ylin(:,IXlin);
aizerochk = abs(airy(0,Lam));
aizerochklin = abs(airy(0,Lamlin));
L
errrms    = sqrt(aizerochk(1:Nfrag)'*aizerochk(1:Nfrag)/(Nfrag+1))
errrmslin    = sqrt(aizerochklin(1:Nfrag)'*aizerochklin(1:Nfrag)/(Nfrag+1))
ain=quad("airynorm",0,100);
figure(1)
plot(ysub(1:3*N/5), Y(1:3*N/5,1));
figure(2)
plot(ysub(1:3*N/5), Y(1:3*N/5,2));
figure(3)
plot(ysub(1:3*N/5), Y(1:3*N/5,Nfrag));

. It uses a Chebyshev spectral method on the extrema grid, and then analyses the results.

I've conducted DuckDuckGo searches for "Sturm-Liouville sagemath" and received no usable results, and as a result I am here to ask, how can one solve Sturm-Liouville problems with SageMath? I know how to do so numerically with Julia, GNU Octave and Scilab, using matrices, but is there any way to solve at least some of them analytically in SageMath (e.g. $\frac{d^2 y}{dx^2}-xy = \lambda y$ has solutions $y_n=C\cdot \textit{Ai}(x+\lambda_n)$, where $\lambda_n$ are the zeros of the Airy $\textit{Ai}(x)$ function, if $y(0)=y(\infty)=0$)? Failing this, is there a way to numerically solve them in SageMath (without resorting to its interfaces with the languages I just mentioned)?

OK, If it helps, here's the code I use in GNU Octave to solve the aforementioned SLE:

# Standard values are for transformation x=(y-L)/(y+L), y in 0, inf
# *lin are for x=2/L*y-1 (linear transformation)
clear all
format long e;
N=5000;
perc=0.266
Nfrag=round(perc*N);
n=0:N;
# 75 at N=1k; 162 for N=3k; 225 for N=5k;
L=226;
t=pi+n'*pi/N;
x=cos(t);
y=L*(cot(t/2)).^2;
ysub=y(2:N);
ylintrans = L/2*(x+1);
# Chebyshev polys of the first kind
T         = cos(t*n);
# Now for arrays that do not include the endpoints
xsub      = x(2:N);
Tsub      = T(2:N,:);
Usub      = diag(1./sqrt(1-xsub.^2))*sin(acos(xsub)*n);
dTsub     = Usub*diag(n);
dT        = [-(n.^2).*(-1).^(n); dTsub ; (n).^2];
dTL       = diag(2*L./((y+L).^2))*dT;
dTlin     = 2/L*dT;
D1        = dTL/T;
D1lin     = dTlin/T;
D2        = D1^2;
D2lin     = D1lin^2;
H         = D2-diag(y);
Hlin      = D2lin-diag(ylintrans);
H         = H(2:N,2:N);
Hlin      = Hlin(2:N,2:N);
[Y, Lam]  = eig(H);
[Ylin, Lamlin] = eig(Hlin);
Lam       = diag(Lam);
Lamlin    = diag(Lamlin);
[Lam, IX] = sort(Lam, 'ascend');
[Lamlin, IXlin] = sort(Lamlin, 'ascend');
Y         = Y(:,IX);
Ylin      = Ylin(:,IXlin);
aizerochk = abs(airy(0,Lam));
aizerochklin = abs(airy(0,Lamlin));
L
errrms    = sqrt(aizerochk(1:Nfrag)'*aizerochk(1:Nfrag)/(Nfrag+1))
errrmslin    = sqrt(aizerochklin(1:Nfrag)'*aizerochklin(1:Nfrag)/(Nfrag+1))
ain=quad("airynorm",0,100);
figure(1)
plot(ysub(1:3*N/5), Y(1:3*N/5,1));
figure(2)
plot(ysub(1:3*N/5), Y(1:3*N/5,2));
figure(3)
plot(ysub(1:3*N/5), Y(1:3*N/5,Nfrag));

. It uses a Chebyshev spectral method on the extrema grid, and then analyses the results.