def add_deformation(chn_names, data):
if "<STR_LIT>" not in chn_names:<EOL><INDENT>for ii, ch in enumerate(chn_names):<EOL><INDENT>if ch == "<STR_LIT>":<EOL><INDENT>chn_names.append("<STR_LIT>")<EOL>data.append(<NUM_LIT:1>-data[ii])<EOL><DEDENT><DEDENT><DEDENT>return chn_names, data<EOL>
From circularity, compute the deformation

    This method is useful for RT-DC data sets that contain
    the circularity but not the deformation.