> Google for web calculator, nothing. https://www.google.com/search?q=atan(42) https://www.google.com/search?q=atan(42) https://www.google.com/search?q=atan(4

> Google for web calculator, nothing. https://www.google.com/search?q=atan(42) https://www.google.com/search?q=atan(42) https://www.google.com/search?q=atan(42)+in+degrees https://www.google.com/search?q=atan(42)+in+degrees (Personally, I usually do quick-and-dirty arithmetic directly in the shell, as ksh expressions include floating point. echo $((atan(42))) )