Hi Ellia,
You need to run "find_pair" first to prepare pairing info for "analyze" to work out the parameters, as shown in the command-line help message:
INPUT
given a PDB file "sample.pdb", the input to analyze can be most
conveniently generated with the utility program find_pair:
find_pair sample.pdb sample.inp
an explicit input file (including 'stdin') must be specified.
EXAMPLES
analyze sample.inp
analyze sample1.inp sample2.inp sample3.inp
find_pair sample.pdb stdout | analyze stdin
find_pair sample.pdb stdout | analyze -c stdin
In other words, this is a two-step process. Using 355d as an example, you need to do the following:
find_pair 355d.pdb 355d.inp
analyze 355d.inp
HTH,
Xiang-Jun