MATLAB: Help me fix the code in which data extracted from a sound file are manipulated

do data mathmatical processingextract data

a sound file with content consisting of 65120 rows of item as following shows
where r[k] corresponds to message. say for example :
r[k] corresponds to the floating point number in first row of the file for k=0.
r[k] corresponds to the floating point number in second row of the file for k=1.
r[k] corresponds to the floating point number in third row of the file for k=2. and so on.
finally, r[k] corresponds to the floating point number in last row of the file for k=65119.
i want to plot s[k] using the following equation s[k]=r[k]-56.97cos(3.6k)-31.98sin(3.6k)
for k=0:length(message)-1
i tried, but again failed.
load message.txt
N=65120;
k=0:N-1;
s = message - 56.97*cosd(3.6*k)-31.98*sind(3.6*k);
s
k=0:N-1;
plot(k,s)
xlabel('k');
could anyone help to fix? thx!

Best Answer

load message.txt
N=65120;
k=0:N-1;
s = message - 56.97*cosd(3.6*k.')-31.98*sind(3.6*k.'); %changed
s
%k=0:N-1; %no need to recalculate it
plot(k,s)
xlabel('k');