gsl-shell.git - gsl-shell

diff --git a/doc/user-manual/matrices.rst b/doc/user-manual/matrices.rst
index 3377a6fc..23f5d05d 100644
--- a/doc/user-manual/matrices.rst
+++ b/doc/user-manual/matrices.rst

@@ -215,10 +215,9 @@ All the functions described in this section have an equivalent function for comp

Return the hermitian conjugate of the matrix.

-.. function:: diag(v)

+.. function:: diag(t)

- Given a column vector ``v`` of length ``n`` returns a diagonal

- matrix whose diagonal elements are equal to the elements of ``v``.

+ Given a table ``t`` of length ``n`` returns a diagonal matrix whose diagonal elements are equal to the elements of ``t``.

.. function:: unit(n)

diff --git a/help/matrix.lua b/help/matrix.lua
index ca1361f2..168f7d16 100644
--- a/help/matrix.lua
+++ b/help/matrix.lua

@@ -60,16 +60,16 @@ matrix.hc(m)

]],

[matrix.diag] = [[

-matrix.diag(v)

+matrix.diag(t)

- Given a column vector "v" of length "n", returns a diagonal

- matrix whose diagonal elements are equal to the elements of "v".

+ Given a table "t" of length "n", returns a diagonal matrix whose

+ diagonal elements are equal to the elements of "t".

]],

[matrix.unit] = [[

matrix.unit(n)

- Return the unit matrix of dimension nxn.

+ Return the unit matrix of dimension n by n.

]],

[matrix.set] = [[

diff --git a/matrix.lua b/matrix.lua
index cbf24590..4e60391b 100644
--- a/matrix.lua
+++ b/matrix.lua

@@ -580,12 +580,9 @@ local complex_mt = {

ffi.metatype(gsl_complex, complex_mt)

local function matrix_new_unit(n)

- local m = matrix_alloc(n, n)

- for i=0, n-1 do

- for j=0, n-1 do

- m.data[i*n+j] = (i == j and 1 or 0)

- end

- end

+ local m = matrix.alloc(n, n)

+ for k = 0, n*n - 1 do m.data[k] = 0 end

+ for k = 0, n-1 do m.data[k*(n+1)] = 1 end

return m

end

@@ -940,16 +937,11 @@ function matrix.svd(a)

return u, s, v

end

-matrix.diag = function(d)

- local n = #d

- local m = d.alloc(n, n)

- local mset, dget = m.set, d.get

- for i=1, n do

- for j= 1, n do

- local x = (i ~= j and 0 or dget(d, i, 1))

- mset(m, i, j, x)

- end

- end

+matrix.diag = function(t)

+ local n = #t

+ local m = matrix.alloc(n, n)

+ for k = 0, n*n - 1 do m.data[k] = 0 end

+ for k = 0, n-1 do m.data[k*(n+1)] = t[k+1] end

return m

end