Linear Algehra

Explanation of tables
*green Function exists in octave 2.0.x
Noted incompatibilities and missing features
+yellow Function exists in matcompat
Author and home for the function.
?orange Function doesn't exist
Explanation of what you can do instead.
xred Function doesn't exist, and no work-around

Generating matrices
*zeros
*ones
*eye
+rand
+randn
Paul Kienzle has rand, randn with long period generator
*linspace
*logspace
*meshgrid

Matrix properties
*size
*length
*isempty
+isequal
Paul Kienzle
*isnumeric
+islogical
Paul Kienzle, but this is done properly in 2.1.x
+logical
Paul Kienzle, but done properly in 2.1.x

Rearranging matrices
*reshape
*tril
*triu
*fliplr
*flipud
xflipdim
*rot90
+repmat
Paul Kienzle
*diag
+blkdiag
Daniel Calvelo
+kron
speedups by Paul Kienzle
*find
+sub2ind
Etienne Grossman, only handles 2D
+ind2sub
Etienne Grossman, only handles 2D

Special matrices
Higham's test matrices provide gallery, compan, hadamard, hilb, invhilb, pascal among others.
?compan
?gallery
?hadamard
Note: sylvester_matrix(n) == hadamard(n) for n=2^k
+hankel
speedups by Paul Kienzle
+hilb
speedups by Paul Kienzle
+invhilb
speedups by Paul Kienzle
+magic
Paul Kienzle, but only handles odd n.
+pascal
+rosser
+toeplitz
speedups by Paul Kienzle
+vander
speedups by Paul Kienzle
+wilkinson
Peter Ekberg provides wilkinson, rosser and pascal

Linear algebra
*norm
*rank
*det
*trace
*null
*orth
+rref
Source adapted by Paul Kienzle.
?subspace
Andrew Knyazev, but noncommercial use only.
*cond
*inv
*pinv
xlscov
*eig
xpolyeig
xcondeig

Matrix factorization
*chol
*lu
*qr
*svd
xgsvd
*hess
*qz
*schur
*balance
xqrdelete
xqrinsert
xrsf2csf
xcdf2rdf
xplanerot
xcholupdate
xqrupdate

Matrix functions
*expm
*logm
*sqrtm
+funm
Paul Kienzle, based on code by Philip Nienhuis