In Magento 2.x, the full error display on frontend is disabled by default. This article shows different methods on how you can see the full error message in your Magento 2 website.
I have written another article on how to Enable/View Full Error Display on Magento 1.x. This one is a similar article for Magento 2.x.

In Magento 1.x, the full error display on frontend is disabled by default. This article shows different methods on how you can see the full error message in your Magento 1 website.
Method 1: View full error from var/report folder

Problem:
– Opened Magento 2 Admin
– Entered the correct admin login information
– And then, got the following error:
Exception #0 (ReflectionException): Class Magento\Authorization\Model\Acl\Role\GroupFactory does not exist

This article shows how you can perform sentiment analysis on movie reviews using Python and Natural Language Toolkit (NLTK).
Sentiment Analysis means analyzing the sentiment of a given text or document and categorizing the text/document into a specific class or category (like positive and negative). In other words, we can say that sentiment analysis classifies any particular text or document as positive or negative. Basically, the classification is done for two classes: positive and negative. However, we can add more classes like neutral, highly positive, highly negative, etc.