Introduction: A graph is supposed to be regular if all vertices have equal degree, otherwise irregular.

Materials and Methods: Polycyclic aromatic hydrocarbons are important combusting material and considered as a class of carcinogens. These polycyclic aromatic hydrocarbons play an important role in graphitisation of medical science. A topological index is a function that assigns a numerical value to a (molecular) graph that predicts various physical, chemical, biological, thermodynamical and structural properties of (molecular) graphs. An irregular index is a topological index that measures the irregularity of atoms with respect to their bonding for the chemical compounds which are involved in the under studying graphs.

Results and Discussion: In this paper, we will compute an analysis of distance based irregular indices of polycyclic aromatic hydrocarbons. A comparison among the obtained indices with the help of their numerical values and the 3D presentations is also included. The efficient and steady indices of polycyclic aromatic hydrocarbons are addressed in the form of their irregularities.

Conclusion: Connection based study of the molecular graphs is more suitable than the degree based irregularity indices.

简介：如果所有顶点的度数相等，则图应该是规则的，否则是不规则的。

材料与方法：多环芳烃是重要的燃烧材料，被认为是一类致癌物。这些多环芳烃在医学的石墨化中发挥着重要作用。拓扑索引是一种函数，它为（分子）图分配数值，预测（分子）图的各种物理、化学、生物、热力学和结构特性。不规则指数是一种拓扑指数，用于测量原子相对于它们与正在研究的图表中所涉及的化合物的键合的不规则性。

结果与讨论：在本文中，我们将计算基于距离的多环芳烃不规则指数的分析。还包括借助其数值和 3D 演示对获得的指数进行比较。多环芳烃的有效和稳定指标以它们的不规则性的形式解决。

结论：基于连接的分子图研究比基于度数的不规则性指标更适合。