update README after del environment.yml file

README.md

@@ -44,8 +44,8 @@ git clone https://github.com/insarlab/PySolid.git
 # option 1: use conda to install dependencies into an existing, activated environment
 conda install -c conda-forge fortran-compiler --file PySolid/requirements.txt
 
-# option 2: use conda to create a new environment named "pysolid"
-conda env create -f PySolid/environment.yml
+# option 2: use conda to install dependencoes into a new environment, e.g. named "pysolid"
+conda create --name pysolid fortran-compiler --file PySolid/requirements.txt
 conda activate pysolid
 
 # option 3: have a Fortran compiler already installed and use pip to install the rest dependencies