Problem
E: Unable to locate package qt4-bin-dbg
E: Package 'qt4-default' has no installation candidate
E: Package 'qt4-doc' has no installation candidate
E: Package 'libqt4-dev' has no installation candidate
E: Unable to locate package libqt4-dev-bin
Solution
sudo add-apt-repository ppa:rock-core/qt4
sudo apt install qt4-default
sudo apt install qt4-bin-dbg
sudo apt install qt4-doc
sudo apt install qt4-dev-tools
sudo add-apt-repository --remove ppa:rock-core/qt4
Problem
E: Package 'python-scipy' has no installation candidate
Solution
Python 2 is EOL, but...
you can still install this package by downloading it from 18.04 LTS repository with
$cd ~/Downloads
$wget http://archive.ubuntu.com/ubuntu/pool/universe/p/python-scipy/python-scipy_0.19.1-2ubuntu1_amd64.deb
$sudo apt-get install ./python-scipy_0.19.1-2ubuntu1_amd64.deb
and then use it was planned.
Note: what is interesting - the 20.04 LTS repository has NumPy, but does not have SciPy. Very strange decision as from user point-of-view.
Follow the original tutorial in a clean Ubuntu
Building and Installing the USRP Open-Source Toolchain (UHD and GNU Radio) on Linux
What you will get
E: Unable to locate package libcppunit-1.14-0
E: Couldn't find any package by glob 'libcppunit-1.14-0'
E: Couldn't find any package by regex 'libcppunit-1.14-0'
E: Package 'python-scipy' has no installation candidate
Sol: Ubuntu 18.04 python2 python-scipy installation
E: Unable to locate package qt4-bin-dbg
E: Package 'qt4-default' has no installation candidate
E: Package 'qt4-doc' has no installation candidate
E: Package 'libqt4-dev' has no installation candidate
E: Unable to locate package libqt4-dev-bin
E: Unable to locate package python-qt4
E: Unable to locate package python-qt4-dbg
E: Unable to locate package python-qt4-dev
E: Unable to locate package python-qt4-doc
E: Unable to locate package python-qt4-doc
E: Unable to locate package libqwt6abi1
E: Unable to locate package libncurses6-dbg
E: Package 'libqt4-dev' has no installation candidate
E: Package 'qt4-default' has no installation candidate
E: Unable to locate package qt4-dev-tools
E: Unable to locate package pyqt4-dev-tools
E: Unable to locate package python-qwt5-qt4
E: Unable to locate package python-gtk2
E: Unable to locate package python-requests
E: Package 'python-sphinx' has no installation candidate
E: Unable to locate package python-zmq
E: Package 'libqwt-dev' has no installation candidate
E: Unable to locate package libqwt6abi1
E: Unable to locate package libgps23
E: Package 'python-gps' has no installation candidate
