When I saw that project on the simple js calculator I immediately thought that it was an opportunity for me to dive into javascript and learn as much as I can about how it works. As an engineering student I wouldn’t be happy with myself if I didn’t built something useful enough to help me with my studies. I already had the idea of how to build it but I didn’t fully know how (where is the fun in that anyways). So I started and never stopped until I got what I imagined in the first place. At this point I have to say a huge thanks to all of the FCC community generally for the help and specially for helping me locating some frustrating bugs that happened along the way. This is by far the most complex app I’ve ever built!
I don’t believe the calculator is perfect yet it must have some bugs left and I would really appreciate it if you bring them to my attention. The features of the calculator are :
On the fly calculation without the need to press the equals button (but with the freedom to do so)
Visible short term history and the ability to erase either each element you typed separately or clear all.
The ability to auto-fill the multiplication symbol if you’re trying to put pi or e or a function after a number or start a parenthesis.
The ability to calculate the result on the fly before you close any parenthesis you might have left open and change the result if you do close them and continue calculating.
Input restriction and result restriction (it’s really high but it’s there).
The negatives are :
Angles are calculated only on rads and it’s not yet responsive. Both are things that I will work on but not yet.
I hope you like it 
here it is : http://codepen.io/periman/full/oYpWWR/
