add description of new feature

JOSS/paper.md

@@ -101,7 +101,7 @@ CompactObject appears as a viable solution to these challenges by providing an o
 
 # The Compactobject package and science use
 
-CompactObject is an open-source software package designed to apply astrophysical and nuclear physics constraints to EOS parameters. Currently, the available EOS options include polytropic EOSs and speed of sound model EOSs, both of which are meta-models. Additionally, the package supports physics-motivated models such as the Relativistic Mean Field (RMF) theory [@Tolos_2016,@Tolos_Centelles_Ramos_2017] and its density-dependent variant [@Hempel_2010,@Char_2014] Beyond neutron star EOS models, CompactObject also includes a strange star EOS based on the strangeon model [@2003ApJ...596L..59X] and the widely used MIT bag model [@PhysRevD.9.3471] for quark stars. 
+CompactObject is an open-source software package designed to apply astrophysical and nuclear physics constraints to EOS parameters. Currently, the available EOS options include polytropic EOSs and speed of sound model EOSs, both of which are meta-models. Additionally, the package supports physics-motivated models such as the Relativistic Mean Field (RMF) theory [@Tolos_2016,@Tolos_Centelles_Ramos_2017] and its density-dependent variant [@Hempel_2010,@Char_2014]. We integrated features for users to define the density dependent variant form by themselves, and which span most of the possibility of this family of models. Beyond neutron star EOS models, CompactObject also includes a strange star EOS based on the strangeon model [@2003ApJ...596L..59X] and the widely used MIT bag model [@PhysRevD.9.3471] for quark stars. 
 
 The package integrates various likelihood constraints, including routines for simulating mass-radius measurements from X-ray timing observations and analyzing mass-radius likelihoods from actual observational data. It also incorporates constraints from radio timing observations, gravitational wave observations related to tidal deformability, and nuclear physics constraints derived from saturation properties, pQCD [@Gorda:2022jvk] [@Providencia:2023rxc]
 and $\chi$EFT [@Hebeler:2013nza] [@Huth:2021bsp]