Editing Guide to madagascar API (section)

==MATLAB interface==

The MATLAB clip function is listed below.
<syntaxhighlight lang="matlab">
function clip(in,out,clip)
%CLIP Clip the data

dims = rsf_dim(in);
n1 = dims(1);           % trace length
n2 = prod(dims(2:end)); % number of traces
trace = 1:n1;           % allocate trace
rsf_create(out,in)      % create an output file

for i2 = 1:n2           % loop over traces
    rsf_read(trace,in,'same');
    trace(trace >   clip) =  clip;
    trace(trace < - clip) = -clip;
    rsf_write(trace,out,'same');
end
</syntaxhighlight>

Let us examine it in detail. 
<syntaxhighlight lang="matlab">
dims = rsf_dim(in);
</syntaxhighlight>

We start by figuring out the input file dimensions.
<syntaxhighlight lang="matlab">
n1 = dims(1);           % trace length
n2 = prod(dims(2:end)); % number of traces
</syntaxhighlight>

The first dimension is the trace length, the product of all other
dimensions correspond to the number of traces.
<syntaxhighlight lang="matlab">
trace = 1:n1;           % allocate trace
rsf_create(out,in)      % create an output file
</syntaxhighlight>

Next, we allocate the trace array and create an output file.
<syntaxhighlight lang="matlab">
for i2 = 1:n2           % loop over traces
    rsf_read(trace,in,'same');
    trace(trace >   clip) =  clip;
    trace(trace < - clip) = -clip;
    rsf_write(trace,out,'same');
end
</syntaxhighlight>

Finally, we do the actual work: loop over input traces, reading,
clipping, and writing out each trace.
===Available functions===
Only some of the functions in the <tt>rsf</tt> library have received a MATLAB interface. These functions are <tt>rsf_par</tt>, <tt>rsf_dim</tt>, <tt>rsf_read</tt>, <tt>rsf_write</tt> and <tt>rsf_create</tt>. All these functions except <tt>rsf_par</tt> have been illustrated in the example above.
===Compiling===
The MATLAB script does not require compilation. Simply make sure that
<tt>&#36;RSFROOT/lib</tt> is in <tt>MATLABPATH</tt> and <tt>LD_LIBRARY_PATH</tt>.