Merge pull request #3 from gha3mi/gha3mi/issue2

Update README

README.md

@@ -4,31 +4,67 @@
 **ForEig**: A Fortran library for eigenvalue and eigenvector calculations.
 
 
-## Installation
+## How to Use ForEig
 
-### fpm
-ForEig can be cloned and then built using [fpm](https://github.com/fortran-lang/fpm), following the instructions provided in the documentation available on Fortran Package Manager.
+### Installation of ForEig Library
 
-```bash
-git clone https://github.com/gha3mi/foreig.git
-cd foreig
-fpm install --prefix .
-```
+To use ForEig, follow the steps below:
+
+- **Reuirements:**
+
+  Fortran Compiler, LAPACK or MKL Libraries
+
+- **Clone the repository:**
+
+   You can clone the ForEig repository from GitHub using the following command:
+
+   ```shell
+   git clone https://github.com/gha3mi/foreig.git
+   cd foreig
+   ```
+
+- **Build using the Fortran Package Manager (fpm):**
+
+   ForEig can be built using [fpm](https://github.com/fortran-lang/fpm).
+   Make sure you have fpm installed, and then execute the following command:
+
+  **GNU Fortran Compiler (gfortran)**
 
-Or you can easily include this package as a dependency in your `fpm.toml` file.
+   ```shell
+   fpm install --prefix . --compiler gfortran --flag "-Wno-line-truncation -Ofast -march=native -llapack"
+   ```
+
+  **Intel Fortran Compiler (ifort)**
+
+   ```shell
+   fpm install --prefix . --compiler ifort --flag "-Ofast -xHost -mtune=native -qmkl=parallel"
+   ```
+
+  **Intel Fortran Compiler (ifx)**
+
+    ```shell
+   fpm install --prefix . --compiler ifx --flag "-Ofast -xHost -mtune=native -qmkl=parallel"
+   ```
+
+### Adding ForEig as an fpm Dependency
+
+If you want to use ForEig as a dependency in your own fpm project,
+you can easily include it by adding the following line to your `fpm.toml` file:
 
 ```toml
 [dependencies]
 foreig = {git="https://github.com/gha3mi/foreig.git"}
 ```
------
 
-## Documentation
-To generate the documentation for the `ForEig` module using [ford](https://github.com/Fortran-FOSS-Programmers/ford) run the following command:
-```bash
+## API Documentation
+
+To generate the API documentation for the `ForEig` module using
+[ford](https://github.com/Fortran-FOSS-Programmers/ford) run the following
+command:
+
+```shell
 ford ford.yml
 ```
------
 
 ## Contributing
 Contributions to `ForEig` are welcome! If you find any issues or would like to suggest improvements, please open an issue or submit a pull request.