The descriptor encompass four types: 1) Stack: each nucleotide is combined with the preceding character to form dimer stacks, numbered from 1 to 16. To comprehensively describe the influence of the surrounding environment, each dimer stack is further combined with its adjacent characters, represented as "XXXX", "(XXX", "XXX)", or "(XX)", where X represents any one of the characters among "A", "T", "C", or "G", and numbered to two decimal places, such as 1.01. 16 dimer stacks in the nearest neighbor model were expanded to a total of 400 stacks. 2) Dangle: nucleotides outside of parentheses and terminated by "." or whitespace are considered as dangles.