Instruct: Classify Amazon reviews into positive or negative sentiment
Query: Hardware too slow for software

I wasted my hard earned money on this calculator. I was so thoroughly disappointed in the calculator that I gave up using it. It was a total and thorough frustration. For example, if you try to graph anything with this calculator, it takes a hundred years (a little exaggeration but expresses the idea) to finish. Even adding simple integers, the calculator would chug along very slowly (e.g. 3+13). Putting the calculator into non-teaching mode (I forgot the actual name for the feature) helped a little though.What attracted me to it was the reviews here and elsewhere. There are some nice features to the calculator. The buttons are nice, the feel of the calculator is nice and the functions are fine as well.However, it is in my opinion a mistake to put this kind of functionality in a calculator without also putting in the hardware to perform the requested operations in a reasonably timely manner. This calculator is not worth more than $20.