Source code:
@Grab(group='org.openscience.cdk', module='cdk-bundle', version='2.9')
import org.openscience.cdk.interfaces.*;
import org.openscience.cdk.io.*;
import org.openscience.cdk.tools.manipulator.*;
import org.openscience.cdk.*;
import java.io.*;
reader = new PDBReader(
new FileReader("data/1CRN.pdb")
);
file = reader.read(new ChemFile());
crambin = ChemFileManipulator
.getAllAtomContainers(file)
.get(0)
println "Crambin has " + crambin.atomCount +
" atoms."
Output:
Crambin has 327 atoms.