Improvements to CrowdAI Plant Disease/tomato disease detection/Tomato_Disease_Prediction.ipynb

[ruhi47]

Add preprocessing steps into a function for better readability. Hyper parameter tuning and visualisation of model performance at the end. I am a GSSOC'24 Contributor, please assign the issue.
Thank you.

[github-actions]

Thanks for creating the issue

[invigorzz313]

This issue has been assigned to you @ruhi47
Do follow the project guidelines for PR

[ruhi47]

Thanks @invigorzz313 !