Some minor bug fixes. Lots of internal improvements and refactoring to support further development.

The main new feature in this version is support for matrixes. Calccis can perform the following matrix calculations: - addition - subtraction - multiplication (also scalar * matrix) - inverse (1/x) - determinant - transposition - dot product for vectors Inputting matrixes is somewhat limited. It is not possible to enter complex or rational values into the matrixes, yet. Other improvements include, among others: - Scientific formatting of numbers (-1.24E-4) works more nicely. - Multiplications and divisions of complex numbers that only have a real or imaginary part use cartesian values for calculation. This change avoids small numerical errors caused by converting the values to polar format, and the use of trigonometrical functions. - Changing the angle unit (Deg -> Rad or vice versa) updates the angle units of complex values in the stack. - There is an edit function, which copies the selected (or topmost) value of the stack to the edit buffer. This feature is currently available for matrixes and plain numerical values only, not for complex numbers or fractions.

Copying and pasting values from Calccis has been improved. It's now possible to paste back all values, including fractions and complex numbers, that have been displayed in Calccis. It's possible to copy any value that is currently shown in the stack. In addition, several bugs have been fixed, including: - calculating the inverse of an integer now returns a floating point value and not a fraction (i.e., calculating 1/x of 5 returns 0.2, not 1/5). - complex numbers with a negative imaginary part should now always be formatted correctly. In some situations, they were formatted like 3 - -2i. - it is no longer possible to input a complex number in polar format with a negative absolute value.

Simple calculations of factorials (n!), permutations (nPr), and combinations (nCr) have been added.

Improve the calculations with fractional numbers. Fractions can now be used in complex numbers, and simple calculations with complex numbers containing fractions work nicely.

Basic calculations with fractions are now available. In addition, there are various smaller corrections and improvements.

New features: - undo and redo - help

The user interface of the app has been re-implemented with SwiftUI. Some colors and visual effects in the UI have been updated slightly.

First version with support for complex numbers.

The calculator status labels are more easily readable. Conversions between decimal and exponent (e.g., 0.00255 and 2.55E-3) number formats have been added.