#1230 changelog

CHANGELOG.md

@@ -13,6 +13,7 @@
 
 ## Optimizations
 
+-   Operations such as `1*x` and `0+x` now directly return `x` ([#1252](https://github.com/pybamm-team/PyBaMM/pull/1252))
 -   Add (optional) smooth approximations for the `Minimum`, `Maximum`, `Heaviside`, and `AbsoluteValue` operators ([#1223](https://github.com/pybamm-team/PyBaMM/pull/1223))
 -   Avoid unnecessary repeated computations in the solvers ([#1222](https://github.com/pybamm-team/PyBaMM/pull/1222))
 -   Rewrite `Symbol.is_constant` to be more efficient ([#1222](https://github.com/pybamm-team/PyBaMM/pull/1222))
@@ -31,7 +32,8 @@
 
 ## Breaking changes
 
--    The parameters "Positive/Negative particle distribution in x" and "Positive/Negative surface area per unit volume distribution in x" have been deprecated. Instead, users can provide "Positive/Negative particle radius [m]" and "Positive/Negative surface area per unit volume [m-1]" directly as functions of through-cell position (x [m]) ([#1237](https://github.com/pybamm-team/PyBaMM/pull/1237)) 
+-   Operations such as `1*x` and `0+x` now directly return `x`. This can be bypassed by explicitly creating the binary operators, e.g. `pybamm.Multiplication(1, x)` ([#1252](https://github.com/pybamm-team/PyBaMM/pull/1252))
+-   The parameters "Positive/Negative particle distribution in x" and "Positive/Negative surface area per unit volume distribution in x" have been deprecated. Instead, users can provide "Positive/Negative particle radius [m]" and "Positive/Negative surface area per unit volume [m-1]" directly as functions of through-cell position (x [m]) ([#1237](https://github.com/pybamm-team/PyBaMM/pull/1237)) 
 
 # [v0.2.4](https://github.com/pybamm-team/PyBaMM/tree/v0.2.4) - 2020-09-07