mmread.m File Reference

Typedefs
using	mmfile = fopen(filename, 'r')

Functions
depending on the Matrix Market format indicated by	coordinate (coordinate sparse storage)
depending on the Matrix Market format indicated by or	array (dense array storage). The data will be duplicated % as appropriate if symmetry is indicated in the header. % % Optionally
	if (mmfile==-1) disp(filename)
	error ('File not found')
	if (length(symm)==0) disp(['Not enough words in header line of file '
filename	disp ('Recognized format:') disp('%%MatrixMarket matrix representation field symmetry') error('Check header line.') end if(~ strcmp(head0
filename MatrixMarket	error ('Not a valid MatrixMarket header.') end if(~ strcmp(head1
filename MatrixMarket matrix	disp (['This seems to be a MatrixMarket ', head1,' file.'])
	disp ('This function only knows how to read MatrixMarket matrix files.')
	disp (' ')
	error (' ')
while	length (commentline) > 0 &commentline(1)
end Read size then branch according to sparse or dense format	if (strcmp(rep, 'coordinate')) % read matrix given in sparse % coordinate matrix format[sizeinfo
	while (count==0) commentline = fgets(mmfile)
	if (commentline==-1) error('End-of-file reached before size information was found.') end[sizeinfo
	if (count > 0 &count ~=3) error('Invalid size specification line.') end end rows = sizeinfo(1)
	fscanf (mmfile,'%f')]
	if (size(T) ~=3 *entries) message
	disp (message)
	error ('Invalid data.')
end	elseif (strcmp(rep, 'array')) % read matrix given in dense % array(column major) format[sizeinfo
	if (strcmp(symm, 'symmetric')|strcmp(symm, 'hermitian')|strcmp(symm, 'skew-symmetric')) for j =1:cols-1
	zeros (j, 1)
	A (currenti+1:length(A))]
id	i ()
elseif(strcmp(field, 'pattern')) % pattern(makes no sense for dense) disp('Matrix type else Unknown matrix type	disp ('Matrix type:', field) error('Invalid matrix type specification. Check header against MM documentation.')
id	appropriate: (diag(A) diag)
	elseif (strcmp(symm, 'hermitian')) A
	elseif (strcmp(symm, 'skew-symmetric')) A
end	fclose (mmfile)

Variables
	function [A, rows, cols, entries, rep, field, symm]
	end
	header = fgets(mmfile)
if(header==-1) error( 'Empty file.') end % NOTE see note	above [head1, header] = strtok(header)
	head1 = lower(head1)
	rep = lower(rep)
	field = lower(field)
	symm = lower(symm)
end Read through	comments
end Read through ignoring them	commentline = fgets(mmfile)
end Read size	information
end Read size then branch according to sparse or dense format	count = sscanf(commentline,'%d%d%d')
	cols = sizeinfo(2)
	entries = sizeinfo(3)
if(strcmp(field, 'real')) % real valued entries	T = [T
	A = sparse(T(:,1), T(:,2), T(:,3), rows , cols)
	currenti = j*rows
elseif(strcmp(field, 'complex')) % complx valued entries	tmpi = fscanf(mmfile,'%f',1)
for	j
end end If	symmetric

Typedef Documentation

mmfile

using mmfile = fopen(filename,'r')

Function Documentation

A()

A

(

currenti+

1:lengthA

)

appropriate:()

id appropriate: ( diag(A)  diag )

virtual

array()

depending on the Matrix Market format indicated by or array

(

dense array

storage

)

coordinate()

depending on the Matrix Market format indicated by coordinate

(

coordinate sparse

storage

)

disp() [1/6]

disp

(

' '

)

disp() [2/6]

elseif(strcmp(field, 'pattern')) % pattern(makes no sense for dense) disp( 'Matrix type else Unknown matrix type disp	(	'Matrix type:'	,
		field
	)

disp() [3/6]

filename disp

(

'Recognized format:'

)

disp() [4/6]

disp

(

'This function only knows how to read MatrixMarket matrix files.'

)

disp() [5/6]

filename MatrixMarket matrix disp

(

)

disp() [6/6]

disp

(

message

)

elseif() [1/3]

end elseif

(

strcmp(rep, 'array')

)

elseif() [2/3]

elseif

(

strcmp(symm, 'hermitian')

)

elseif() [3/3]

elseif

(

strcmp(symm, 'skew-symmetric')

)

error() [1/4]

error

(

' '

)

error() [2/4]

error

(

'File not found'

)

error() [3/4]

error

(

'Invalid data.'

)

error() [4/4]

filename MatrixMarket error

(

'Not a valid MatrixMarket header.'

)

fclose()

end fclose

(

mmfile

)

fscanf()

fscanf	(	mmfile	,
		'%f'
	)

i()

id i ( )

staticvirtual

if() [1/7]

if

(

commentline

= = -1

)

if() [2/7]

if	(	count	,
		0 &count ~	= 3
	)		= sizeinfo(1)

if() [3/7]

if

(

length(symm)

= = 0

)

if() [4/7]

if

(

mmfile

= =-1

)

if() [5/7]

if

(

size(T) ~

= 3 *entries

)

Initial value:

= ...
       str2mat('Data file does not contain expected amount of data.',...
               'Check that number of data lines matches nonzero count.')

if() [6/7]

end Read size then branch according to sparse or dense format if

(

strcmp(rep, 'coordinate')

)

if() [7/7]

end if

(

strcmp(symm, 'symmetric')|strcmp(symm, 'hermitian')|strcmp(symm, 'skew-symmetric')

)

=1:cols-1

length()

while length

(

commentline

)

&

while()

while

(

count

= =0

)

= fgets(mmfile)

zeros()

zeros	(	j	,
		1
	)

Variable Documentation

A

A = sparse(T(:,1), T(:,2), T(:,3), rows , cols)

above

if (header == -1 ) error('Empty file.') end % NOTE see note above[head1, header] = strtok(header)

cols

cols = sizeinfo(2)

commentline

while commentline = fgets(mmfile)

comments

end Read through comments

count

end count = sscanf(commentline,'%d%d%d')

currenti

end currenti = j*rows

end

end

entries

entries = sizeinfo(3)

field

field = lower(field)

function

function[A, rows, cols, entries, rep, field, symm]

Initial value:

= mmread(filename)
%
% function  [A] = mmread(filename)
%
% function  [A,rows,cols,entries,rep,field,symm] = mmread(filename)
%
%      Reads the contents of the Matrix Market file 'filename'
%      into the matrix 'A'.  'A' will be either sparse or full

head1

head1 = lower(head1)

header

header = fgets(mmfile)

information

end Read size information

j

for j

Initial value:

=1:entries-1
      tmpr = fscanf(mmfile,'%f',1)

rep

rep = lower(rep)

symm

symm = lower(symm)

symmetric

end end If symmetric

T

end T = [T

tmpi

tmpi = fscanf(mmfile,'%f',1)