filename=fopen('heartbeatn1nn.txt');
A = textscan(filename,'%f','HeaderLines',0);
fclose(filename);

filename=fopen('heartbeatn1nn.txt');
formatSpec='%f';sizeA=[1 Inf];
A = fscanf(filename,formatSpec,sizeA);
fclose(filename);

A = textscan(filename,'%f %s %f');

first_col = A{:,1};

first_col = cell2mat( textscan(filename, '%f %*s %*f') );