Topic: Expressions

## Constants

#### Real

Real constants can be positive and negative integer and decimal numbers. They can include digits "0" - "9" and decimal point ".". You can also enter numbers as fractions like "3/4". However, the program will treat them as expressions (division of two numbers). You cannot define numbers in floating point format: "3.4e+6". You have to use an expression like "3.4*10^6" instead.

All constants and variables are internally stored as "double-precision floating point" numbers. Their values are ranged from -1.7976931348623157E+308 to 1.7976931348623157E+308. If a result is out of the above interval, the program returns "-∞" or "+∞, respectively". Division by zero gives the same result, but "0/0" = "Undefined". The smallest positive number is 4.94065645841247E-324. Smaller values are rounded exactly to 0.

#### Complex

If you select "Complex" mode, you can use complex numbers in calculations. Otherwise, only real arithmetic is applied. Each complex number is represented by the ordered couple (a; b), where "a" is real number, and "b = |b|i" is called "imaginary". It can be written in so called algebraic form: ±a ± bi (e.g. "2 + 3i"). You can also use other forms, such as polar or exponential from, by entering the respective expressions. In Calcpad, the imaginary unit can be entered either as "i" or "1i" in case you have a variable named "i". The imaginary unit is a special number that satisfies the expression i 2 = -1.