Enhance README with data and methods information

README.md

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 limitations under the License.
 
 
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+
+The aim of this repository is to provide details of the data sets and code used in the related research titled *Interior-Point vs. Spatial Branching Approaches for Solving the AC Optimal Power Flow Problem*.
+
+## Data Description
+
+The following test systems are included in this repository:
+
+* `case14`, `tuned14`: IEEE 14-bus test systems (original and tuned versions).  
+* `case39`, `tuned39`: IEEE 39-bus test systems (original and tuned versions).  
+* `case57`, `tuned57`: IEEE 57-bus test systems (original and tuned versions).  
+* `case118`, `tuned118`: IEEE 118-bus test systems (original and tuned versions).
+
+*Tuned variants incorporate modifications from Narimani et al. (2018) (14- and 57-bus) and Bukhsh et al. (2013) (39- and 118-bus) to enhance the presence of local minima.*
+
+## Methods
+
+Two main approaches were implemented and compared:
+
+**Interior-Point (IP):**
+- `IP-R-F`: Rectangular formulation with flat voltage initialization.  
+- `IP-R-H`: Rectangular formulation with nearest historical operating point initialization.  
+- `IP-P-F`: Polar formulation with flat voltage initialization.  
+- `IP-P-H`: Polar formulation with most similar historical demand initialization.  
+
+**Spatial Branching (SP):**
+- `SP-O`: Original voltage bounds from operational limits.  
+- `SP-ε`: Artificially tightened bounds around the optimal solution.  
+- `SP-K`: Data-boosted bounds learned from *K* nearest historical operating points.  
+
+## Developed by
+
+* **Ignacio Repiso López** ([irepiso@uma.es](mailto:irepiso@uma.es)) - [GitHub: IgnacioRepiso](https://github.com/IgnacioRepiso)  
+* **Salvador Pineda** ([spineda@uma.es](mailto:spineda@uma.es)) - [GitHub: salvapineda](https://salvapineda.github.io/)  
+* **Juan Miguel Morales** ([jmmorales@uma.es](mailto:juan.mmorales@uma.es)) - [GitHub: juanmi82mg](https://juanmi82mg.github.io/)
+
+## Funding
+
+This work was supported in part by the Spanish Ministry of Science and Innovation (AEI/10.13039/501100011033) through project PID2023-148291NB-I00.  
+I. Repiso, S. Pineda, and J. M. Morales are with the research group OASYS, University of Málaga, Málaga 29071, Spain.  
+The work of I. Repiso was supported by the Spanish Ministry of Science and Innovation training program for PhDs with fellowship number PRE2023-002227.  
+Finally, the authors thankfully acknowledge the computer resources, technical expertise, and assistance provided by the SCBI (Supercomputing and Bioinformatics) center of the University of Málaga.
+
+## How to cite the repo and the paper?
+
+If you want to cite the related paper or this repository, please use the following bib entries:
+
+* Article:
+
+
+