Bug#805986: gnome-calculator: Operations with complex numbers

[Andrea Stacchiotti]

Package: gnome-calculator
Version: 3.18.2-1
Severity: normal

Dear maintainer,
operations with complex numbers have some surprising results in gnome-
calculator.

while e^(a*i*Pi) seems to give the correct result for every a in R, other
related operations don't work as well:

* Integer power: z^n, z in C, n in N, returns z even if it makes no sense,
while z*z, for example, works fine.
If n is not positive, strange things happen, depending on inputs.

Reproduce with i^2, i^(-1), i^(-2)

* Hyperbolic fuctions: sinh(ai), cosh(ai) and tanh(ai) always return 0 and 1,
instead of the proper value.
With some testing, they seem to return f(Re(z)) instead of f(z).

Consider telling the user those functions are unsupported for some arguments,
like the factorial does.



-- System Information:
Debian Release: stretch/sid
  APT prefers unstable
  APT policy: (500, 'unstable'), (1, 'experimental')
Architecture: amd64 (x86_64)
Foreign Architectures: i386

Kernel: Linux 4.2.0-1-amd64 (SMP w/4 CPU cores)
Locale: LANG=it_IT.UTF-8, LC_CTYPE=it_IT.UTF-8 (charmap=UTF-8)
Shell: /bin/sh linked to /bin/dash
Init: systemd (via /run/systemd/system)

Versions of packages gnome-calculator depends on:
ii  dconf-gsettings-backend [gsettings-backend]  0.24.0-2
ii  libatk1.0-0                                  2.18.0-1
ii  libc6                                        2.19-22
ii  libcairo-gobject2                            1.14.4-1
ii  libcairo2                                    1.14.4-1
ii  libgdk-pixbuf2.0-0                           2.32.2-1
ii  libglib2.0-0                                 2.46.2-1
ii  libgmp10                                     2:6.1.0+dfsg-2
ii  libgtk-3-0                                   3.18.5-1
ii  libgtksourceview-3.0-1                       3.18.1-1
ii  libmpfr4                                     3.1.3-1
ii  libpango-1.0-0                               1.38.1-1
ii  libpangocairo-1.0-0                          1.38.1-1
ii  libxml2                                      2.9.2+zdfsg1-4

Versions of packages gnome-calculator recommends:
ii  gvfs  1.26.2-1
ii  yelp  3.16.1-1

gnome-calculator suggests no packages.

-- no debconf information