read_sparse.m

matlab实现

function [svm_lbl, svm_data] = read_sparse(fname); 
row = []; 
col = []; 
value = []; 

fid = fopen(fname); 
line=0; 
svm_lbl=[]; 
svm_data=[]; 
while 1 
	tline = fgetl(fid); 
	line = line + 1; 
	if ~ischar(tline), break, end 
	[lbl, data] = strtok(tline); 

	svm_lbl(line, 1) = sscanf(lbl, '%g'); 
	[c, v] = strread(data, '%d:%f'); 
	row = [row; line * ones(length(c), 1)]; 
	col = [col; c]; 
	value = [value; v]; 
end 

svm_data = sparse(row, col, value); 

fclose(fid);