3 errors in a script line - 11, 13, 28

'Shock Response Spectrum';
'CrLf';
ymax=[ ];
ff=[ ];
fmin=1;
fmax=1000;
n=90;
qv=(fmax/fmin)^(1/n);
T=1/get(input1,'freq');
Q=10;
for[i=0;1;1i<n;i=i+1];
{
 fn=[fmin*qv^i];
 ff=[ff,fn];
 wn=2*pi*fn;
 A=wn*T/2/Q;
 B=wn*T*sqr(1-1/4/Q/Q);
 b0=1-exp(-A)*sin(B)/B;
 b1=2*exp(-A)*(sin(B)/B-cos(B));
 b2=exp((-2)*A)-exp(-A)*sin(B)/B;
 a1=(-2)*exp((-1)*A)*cos(B);
 a2=exp((-2)*A);
 BB=[b0,b1,b2];
 AA=[-a1,-a2];
 y=filter(input1,BB,AA);
 yy=max(y);
 ymax=[ymax,yy];
};
save(ff);
save(ymax);

Answer 1

[DGM]

T=1/get(input1,'freq');

input1 is a missing variable/object, so you'll have to figure that out. If this is is someone else's code, I have less information than you do about what it could possibly be.

for[i=0;1;1i<n;i=i+1];
{
    % ...
};

I have no idea what language this is from, but it's not MATLAB. I am not familiar with any 4-argument for loop syntax, so I have no idea what the 1 means. You're using i as both an integer index and you're attempting to explicitly use it as a complex number. Both i and j are sqrt(-1). Unless you're using them as that, don't cause problems by overloading them for use as indices or something.

B=wn*T*sqr(1-1/4/Q/Q);

I'm assuming that's supposed to be sqrt()?

y=filter(input1,BB,AA);

Again, I'm assuming input1 is some variable you have already.

Without the missing variable, this is my best guess:

clc; clearvars

ymax=[ ];
ff=[ ];
fmin=1;
fmax=1000;
n=90;
qv=(fmax/fmin)^(1/n);
%T=1/get(input1,'freq');
T = 1/200; % fake number to make it run
Q=10;
for k = 0:n-1 % is this right?
	fn=fmin*qv^k;
	ff=[ff,fn];
	wn=2*pi*fn;
	A=wn*T/2/Q;
	B=wn*T*sqrt(1-1/4/Q/Q);
	b0=1-exp(-A)*sin(B)/B;
	b1=2*exp(-A)*(sin(B)/B-cos(B));
	b2=exp((-2)*A)-exp(-A)*sin(B)/B;
	a1=(-2)*exp((-1)*A)*cos(B);
	a2=exp((-2)*A);
	BB=[b0,b1,b2];
	AA=[-a1,-a2];
	%y=filter(input1,BB,AA);
	y=filter(BB,BB,AA); % just cram something in it so it runs
	yy=max(y);
	ymax=[ymax,yy];
end

[Walter Roberson]

I am wondering if

for[i=0;1;1i<n;i=i+1];

is some kind of combination of

for i=0:1:1

and a C / C++

 for (i=0; i <n; i++)