A basic calculator web page.
Calculates from left to right, not by order of operations.
If an operator is the last character in the expression string, a default value of 0 is used for addition/subtraction and a default value of 1 is used for multiplication/division.
Results that include decimals are trimmed to 5 digits after the decimal-- rounding is not implemented.
To-Do:
- clean up the calculator using CSS
- allow keyboard input
- round results that are too long