Error in cds_srr (line 20)

Hi, 
In the MATLAB, I am using cds_srr and cds_innersrr commands. Although I set the path to the spectre root, I face this error:

One or more output arguments not assigned during call to "cds_innersrr".

Error in cds_srr (line 20)
sig = cds_innersrr(dirname, dataset, signame, verbose);

Error in techsweep_spectre_run (line 64)
struct_n = cds_srr(c.outfile, c.sweep, params_n{1});

I would highly appreciate it if you could help me.