Mercurial > hg > octave-nkf
changeset 11458:93a039fe681e
logm: style fixes
author | John W. Eaton <jwe@octave.org> |
---|---|
date | Fri, 07 Jan 2011 14:14:35 -0500 |
parents | 33f6384d2b78 |
children | 990c9cb52e5f |
files | scripts/ChangeLog scripts/linear-algebra/logm.m |
diffstat | 2 files changed, 18 insertions(+), 20 deletions(-) [+] |
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--- a/scripts/ChangeLog +++ b/scripts/ChangeLog @@ -1,3 +1,7 @@ +2011-01-07 John W. Eaton <jwe@octave.org> + + * linear-algebra/logm.m: Style fixes. + 2011-01-06 John W. Eaton <jwe@octave.org> * optimization/optimset.m: Remove "i" option from call to
--- a/scripts/linear-algebra/logm.m +++ b/scripts/linear-algebra/logm.m @@ -39,18 +39,14 @@ ## (SIAM, 2008.) ## -function [s, iters] = logm (a, opt_iters) +function [s, iters] = logm (a, opt_iters = 100) - if (nargin == 0) - print_usage (); - elseif (nargin < 2) - opt_iters = 100; - elseif (nargin > 2) + if (nargin == 0 || nargin > 2) print_usage (); endif if (! issquare (a)) - error ("logm: argument must be a square matrix."); + error ("logm: argument must be a square matrix"); endif [u, s] = schur (a); @@ -61,9 +57,7 @@ if (any (diag (s) < 0)) warning ("Octave:logm:non-principal", - ["logm: Matrix has negative eigenvalues.", ... - " Principal matrix logarithm is not defined.", ... - " Computing non-principal logarithm."]); + "logm: principal matrix logarithm is not defined for matrices with negative eigenvalues; computing non-principal logarithm"); endif k = 0; @@ -87,7 +81,7 @@ endwhile if (k >= opt_iters) - warning ("logm: Maximum number of square roots exceeded. Results may still be accurate."); + warning ("logm: maximum number of square roots exceeded; results may still be accurate"); endif s = logm_pade_pf (s - eye (size (s)), m); @@ -111,16 +105,16 @@ ## Y = LOGM_PADE_PF(a,M) evaluates the [M/M] Pade approximation to ## LOG(EYE(SIZE(a))+a) using a partial fraction expansion. -function s = logm_pade_pf(a,m) - [nodes,wts] = gauss_legendre(m); +function s = logm_pade_pf (a, m) + [nodes, wts] = gauss_legendre (m); ## Convert from [-1,1] to [0,1]. - nodes = (nodes + 1)/2; + nodes = (nodes+1)/2; wts = wts/2; - n = length(a); - s = zeros(n); - for j=1:m - s = s + wts(j)*(a/(eye(n) + nodes(j)*a)); + n = length (a); + s = zeros (n); + for j = 1:m + s += wts(j)*(a/(eye (n) + nodes(j)*a)); endfor endfunction @@ -133,10 +127,10 @@ ## G. H. Golub and J. H. Welsch, Calculation of Gauss quadrature ## rules, Math. Comp., 23(106):221-230, 1969. -function [x,w] = gauss_legendre(n) +function [x, w] = gauss_legendre (n) i = 1:n-1; v = i./sqrt ((2*i).^2-1); - [V,D] = eig ( diag(v,-1)+diag(v,1) ); + [V, D] = eig (diag (v, -1) + diag (v, 1)); x = diag (D); w = 2*(V(1,:)'.^2); endfunction