‘catkin_make‘ is currently not installed问题修复

$ cd ~/catkin_ws/
$ catkin_make

``
The program ‘catkin_make’ is currently not installed. You can install it by typing:
sudo apt install catkin

So I do that, and get
``
Reading package lists... Done
Building dependency tree
Reading state information... Done
Some packages could not be installed. This may mean that you have
requested an impossible situation or if you are using the unstable
distribution that some required packages have not yet been created
or been moved out of Incoming.
The following information may help resolve the situation:

The following packages have unmet dependencies:
 catkin : Depends: python-catkin-pkg but it is not going to be installed
E: Unable to correct problems, you have held broken packages.

原因

我之前因为要使用python opencv，但是opencv和ROS互斥，于是把ROS的source去掉了

解决：

在终端中：

source /opt/ros/kinetic/setup.bash 
source ~/.bashrc
export SVGA_VGPU10=0

参考：
https://answers.ros.org/question/258444/sudo-apt-install-catkin-not-working/