Error using zeros, Size inputs must be integers

Hi, I have problem with run below code could anyone solve it?

error:

Error using zeros

Size inputs must be integers.

Error in make_image (line 25)

rf_env=abs(hilbert([zeros(tstart*fs-min_sample,1); rf_data]));

code:

f0=3.5e6;                 %  Transducer center frequency [Hz]
fs=100e6;                 %  Sampling frequency [Hz]
c=1540;                   %  Speed of sound [m/s]
no_lines=50;              %  Number of lines in image
d_x=40/1000/no_lines;     %  Increment for image

%  Read the data and adjust it in time 

min_sample=0;
for i=1:no_lines

  %  Load the result

  cmd=['load sim_bmd/rf_ln',num2str(i),'.mat']
  eval(cmd)
  
  %  Find the envelope
  
  if (tstart>0)
    rf_env=abs(hilbert([zeros(tstart*fs-min_sample,1); rf_data]));
  else
    rf_env=abs(hilbert( rf_data( abs(tstart*fs):max(size(rf_data)) ) ));
    end
  env(1:max(size(rf_env)),i)=rf_env;
  end

%  Do logarithmic compression

D=20;   %  Sampling frequency decimation factor

log_env=env(1:D:max(size(env)),:)/max(max(env));
log_env=log(log_env+0.01);
log_env=log_env-min(min(log_env));
log_env=64*log_env/max(max(log_env));

%  Make an interpolated image

ID_bmode=10;
[n,m]=size(log_env)
new_env=zeros(n,m*ID_bmode);
for i=1:n
  if(rem(i,100) == 0)
    i
    end
  new_env(i,:)=abs(interp(log_env(i,:),ID_bmode));
  end
[n,m]=size(new_env)
  
fn_bmode=fs/D;
clg
image(((1:(ID_bmode*no_lines-1))*d_x/ID_bmode-no_lines*d_x/2)*1000,((1:n)/fn_bmode+min_sample/fs)*1540/2*1000,new_env)
xlabel('Lateral distance [mm]')
ylabel('Axial distance [mm]')
colormap(gray(64))
%brighten(-0.35)
%axis([-20 20 30 90])
axis('image')

[KSSV]

It looks like you are using indices as fractions. This is not allowed. The indices should be positive integers.

A = rand(1,10); 
A(0)  % error 
A(1.5)  % error

[Adam Danz]

zeros(tstart*fs-min_sample,1)

The problem is likely with tstart and that variable is probably not an integer.

[mr de]

This code is part of exmple link below how can I correct it?

https://field-ii.dk/?examples/cfm_example/cfm_example.html

[Adam Danz]

I'm not going to study this topic for you and try to search through the links on that page to find the releveant section of code that you need to learn. At the very least you could find the exact URL that contains the exact code and find the exact line and then copy that relevant section into a comment so other people don't have to search the internet just to understand what you're asking. You invest hours before we invest minutes.

[Steven Lord]

This section of the code caught my eye as particularly bad.

  cmd=['load sim_bmd/rf_ln',num2str(i),'.mat']
  eval(cmd)

There is no need to call eval here. [There are limited times when you need to call eval at all.] Use the function form of load. I also recommend calling load with an output argument to read the data from the file into a struct array to avoid potentially overwriting variables that already exist with ones from the MAT-file.

theName = ['sim_bmd/rf_ln' num2str(i) '.mat'];
theData = load(theName)

% to refer to a variable named x from the file (as an example)
theData.x