Update to v0.92

CompoundMatrixMethod/CompoundMatrixMethod.m

@@ -3,13 +3,13 @@
 (* Mathematica Package  *)
 
 (* :Title: CompoundMatrixMethod *)
-(* :Author: Simon Pearce <[email protected]> *)
+(* :Author: Simon Pearce <simon.pearce@cruk.manchester.ac.uk> *)
 (* :Context: CompoundMatrixMethod` *)
-(* :Version: 0.91 *)
-(* :Date: 2022-02-09 *)
+(* :Version: 0.92 *)
+(* :Date: 2022-01-15 *)
 
 (* :Mathematica Version: 10+ *)
-(* :Copyright: (c) 2017-22 Simon Pearce *)
+(* :Copyright: (c) 2017-23 Simon Pearce *)
 
 BeginPackage["CompoundMatrixMethod`"];
 
@@ -389,7 +389,7 @@ with radius controlled by ContourRadius (default 1), for a system defined from T
 			FMatrix = ExtractInterface[interfaceBCs, depvarLeft, {x, xmatch}];
 			GMatrix = ExtractInterface[interfaceBCs, depvarRight, {x, xmatch}];
 			{leftAMatrix, leftBCMatrix, stuff, xLeft} =		  ToMatrixSystem[leftEqns, leftBCs, depvarLeft, {x, xa, xmatch}, a];
-			{rightAMatrix, stuff, rightBCMatrix, xRight} = 	ToMatrixSystem[rightEqns, rightBCs,	depvarRight, {x, xmatch, xb}, a];
+			{rightAMatrix, stuff, rightBCMatrix, xRight} = 	ToMatrixSystem[rightEqns, rightBCs, depvarRight, {x, xmatch, xb}, a];
 			(*Return the system for using in CMM function*)
 			{{leftAMatrix, rightAMatrix}, leftBCMatrix,rightBCMatrix, {FMatrix,	GMatrix}, {x, xa, xmatch, xb}} /. a -> \[FormalLambda]
 
@@ -418,7 +418,7 @@ with radius controlled by ContourRadius (default 1), for a system defined from T
 			(*Replace all the original variables with a set indexed by Y*)
 			newYs = Through[Array[\[FormalY], {Length[originalYVariables]}][x]];
 			newYSubs = Thread[originalYVariables -> newYs];
-			Transpose[Table[Coefficient[neweqn /. newYSubs /. Equal -> Subtract, i], {i, newYs}]]
+			Transpose[Table[Coefficient[neweqn /. newYSubs /. Equal -> Subtract, i], {i, Join[newYs,undifferentiatedVariables]}]]
 		]
 
 SelectNegativeEigenvectors[mat_?MatrixQ, x_ /; !NumericQ[x]] := Module[{limitMatrix,eigvecs},
@@ -442,6 +442,16 @@ with radius controlled by ContourRadius (default 1), for a system defined from T
 	leftBCMatrix_?MatrixQ, rightBCMatrix_?MatrixQ, {FMatrix_?MatrixQ,	GMatrix_?MatrixQ}, {x_ /; ! NumericQ[x], xa_, xm_, xb_}},opts:OptionsPattern[{Evans,NDSolve}]] :=
 		Evans[\[FormalLambda]0, {ALeftMatrix,	ARightMatrix}, leftBCMatrix, rightBCMatrix,	{FMatrix,	GMatrix}, {x, xa, xm, xb},opts]
 
+Evans[\[FormalLambda]0_?NumericQ, {{ALeftMatrix_?MatrixQ,ARightMatrix_?MatrixQ},{}, rightBCMatrix_?MatrixQ, {FMatrix_?MatrixQ,GMatrix_?MatrixQ}, {x_ /; ! NumericQ[x], xa_, xm_, xb_}},opts:OptionsPattern[{Evans,NDSolve}]] :=
+  Evans[\[FormalLambda]0, {ALeftMatrix,ARightMatrix}, N@SelectNegativeEigenvectors[ALeftMatrix /. \[FormalLambda] -> \[FormalLambda]0, x], rightBCMatrix,{FMatrix,GMatrix}, {x, xa, xm, xb},opts]
+
+Evans[\[FormalLambda]0_?NumericQ, {{ALeftMatrix_?MatrixQ,ARightMatrix_?MatrixQ},leftBCMatrix_?MatrixQ, {}, {FMatrix_?MatrixQ,GMatrix_?MatrixQ}, {x_ /; ! NumericQ[x], xa_, xm_, xb_}},opts:OptionsPattern[{Evans,NDSolve}]] :=
+  Evans[\[FormalLambda]0, {ALeftMatrix,ARightMatrix}, leftBCMatrix, N@SelectNegativeEigenvectors[ARightMatrix /. \[FormalLambda] -> \[FormalLambda]0, x],{FMatrix,GMatrix}, {x, xa, xm, xb},opts]
+
+Evans[\[FormalLambda]0_?NumericQ, {{ALeftMatrix_?MatrixQ,ARightMatrix_?MatrixQ},{}, {}, {FMatrix_?MatrixQ,GMatrix_?MatrixQ}, {x_ /; ! NumericQ[x], xa_, xm_, xb_}},opts:OptionsPattern[{Evans,NDSolve}]] :=
+  Evans[\[FormalLambda]0, {ALeftMatrix,ARightMatrix}, N@SelectNegativeEigenvectors[ALeftMatrix /. \[FormalLambda] -> \[FormalLambda]0, x], N@SelectNegativeEigenvectors[ARightMatrix /. \[FormalLambda] -> \[FormalLambda]0, x],{FMatrix,GMatrix}, {x, xa, xm, xb},opts]
+
+
 Evans[\[FormalLambda]0_?
 		NumericQ, {ALeftMatrix_?MatrixQ,	ARightMatrix_?MatrixQ}, leftBCMatrix_?MatrixQ, rightBCMatrix_?MatrixQ,
 	{FMatrix_?MatrixQ,	GMatrix_?MatrixQ}, {x_ /; !NumericQ[x], xaa_, xmm_, xbb_},opts:OptionsPattern[{Evans,NDSolve}]] :=

CompoundMatrixMethod/PacletInfo.m

@@ -3,7 +3,7 @@
 (* ::Input::Initialization:: *)
 Paclet[
 Name->"CompoundMatrixMethod",
-Version->"0.91",
+Version->"0.92",
 MathematicaVersion->"10+",
 Description->"Solve Eigenvalue Boundary Value Problems using the Compound Matrix Method to generate the Evans function. ",
 Creator->"Simon Pearce",

README.md

@@ -20,6 +20,8 @@ The package can then be loaded by calling
 
 The Compound Matrix Method is a package for finding eigenvalues of boundary-value ordinary differential equations.
 
+This includes problems with a single interface, decaying conditions at one or both ends, in an upto 10th order differential system.
+
 First we need to transform the boundary-value problem (BVP) into a set of first order matrix equations. The function ToMatrixSystem will do this, linearising the equations if necessary (with a warning if it does). 
 
         sys=ToMatrixSystem[y''[x] + k^2 y[x] == 0, {y[0] == 0, y[1] == 0}, y, {x, 0, 1}, k]
@@ -47,13 +49,12 @@ A number of further examples are shown in the file `CMMExamples.nb`, available f
 
 I used this method to solve an eigenvalue problem in <a href=https://doi.org//10.1093/imamat/hxq026>my 2010 paper </a>, and the package itself in both <a href=https://link.springer.com/article/10.1007/s11538-018-0505-4>a tenth-order ODE </a> as well as <a href=https://journals.aps.org/pre/abstract/10.1103/PhysRevE.98.033003>an example with an interface</a>. 
 
-I'm currently working on an expository paper to detail how the method works and introduce the package.  
+I have a half-written expository paper (expansion of the <a href=http://www.maths.gla.ac.uk/~xl/FYB-background.pdf>note</a> written by Professor Yibin Fu) to give more details on how the method works and introduce the package, please email me for a copy of that. 
 
 ## Contact
 
-Feel free to contact me if you have any questions, suggestions or issues, I'm also interested in collaborations involving this work.
-My email address is simon (dot) pearce (at) manchester (dot) ac (dot) uk. 
+Feel free to contact me if you have any questions, suggestions or issues, I'm also interested in collaborations involving this work, but please note my time is severely limited as I am no longer active in this field. My email address is simon (dot) pearce (at) cruk (dot) manchester (dot) ac (dot) uk. 
 
 ## Funding Acknowledgement
 
-This code was initially written while I held an Early Career Fellowship from the <a href=https://www.leverhulme.ac.uk>Leverhulme Trust</a>. I'm now based at the Cancer Research UK Manchester Institute, part of the University of Manchester, UK.
+This code was initially written while I held an Early Career Fellowship from the <a href=https://www.leverhulme.ac.uk>Leverhulme Trust</a>. I'm now based at the Cancer Research UK Manchester Institute, part of the University of Manchester, UK, and work on bioinformatics.