A simple linear calculator. It can evaluate linear expressions with these symbols:

• Operators including: + (plus); - (minus); * (multiply); / (divide); ^ (power); E (scientific expression, for example 2E3 means 2*10^3=2000).
• Functions including: sqrt (square root); sin, cos, tan, cot, sec, csc (trigonometric functions, additionally, you can express a number in degrees by adding deg or ° after it, for example 90 deg means π/2); log, ln (separately 10 based logarithm and natural logarithm).
• Consts including: pi (π, or you can simply input π if that's easier); en (commonly as e, but conflicting with the E operation above so its expressed as en).

You can find the calculation history by pressing up and down in the textbox.

You can also expand the calculator by clicking the triangle in the right-bottom corner. It will allow you to input some functions with buttons, and additionally provides a variable feature. You can directly edit the variables "M1" to "M4" in their belonging textboxes, or click the "←" button in the right to import the current expression in the main textbox. By pressing the "M1" to "M4" buttons in their left, you can input the variables to the main texbox (or you can also simply type it in).

Any character that's not supported here will be ignored (as space, which differs as two numbers separated by space will multiply).