@Dee T - You could try Azure Text Analytics. It is a cloud service that provides Natural Language Processing (NLP) features for text mining and text analysis.
The below are few of the analysis features included with the service :
- Sentiment analysis
- Opinion mining
- Key phrase extraction
- Language detection
- Named entity recognition.
A sample analysis of text can be found at https://azure.microsoft.com/en-in/services/cognitive-services/text-analytics/#features
You could refer this article to get started with the Text Analytics https://learn.microsoft.com/en-in/azure/cognitive-services/text-analytics/
Note :
Currently, service can analyze the document with max size of 5120 characters. Reading through your requirement, I understand that you may have a requirement of analyzing larger document (above the mentioned limit).
You will be able to meet your goal by splitting the large documents into chunks and combining all the results. You could refer this article for more information : Analyzing Large Documents
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