我不是Linux的有经验的用户。但是我只想在Ubuntu 18.04上安装最新版本的GRASS GIS和QGIS。我猜有很多不同的方法可以做到这一点。有PPA，有ubuntu的常规qgis存储库，还有ubuntugis。有点令人不知所措，在安装QGIS的过程中，我认为我搞砸了一些事情。
当我运行sudo nano /etc/apt/sources.list时，我添加了这两个存储库：
deb http://qgis.org/ubuntu bionic main
deb-src http://qgis.org/ubuntu bionic main
然后我执行此处提供的所有步骤：
https://qgis.org/en/site/forusers/alldownloads.html#debian-ubuntu
但是当我运行sudo apt install qgis时，我得到：
The following packages have unmet dependencies:
qgis : Depends: gdal-abi-2-2-3 but it is not installable
Depends: libqgis-analysis3.10.2 but it is not going to be installed
Depends: libqgis-app3.10.2 but it is not going to be installed
Depends: libqgis-core3.10.2 but it is not going to be installed
Depends: libqgis-gui3.10.2 but it is not going to be installed
Depends: python3-qgis (= 1:3.10.2+28bionic) but it is not going to be installed
Depends: qgis-providers (= 1:3.10.2+28bionic) but it is not going to be installed
Recommends: qgis-plugin-grass but it is not going to be installed
E: Unable to correct problems, you have held broken packages.
我不知道这与我尝试添加PPA一次有关。当我运行ls /etc/apt/sources.list.d/时，我得到：
...
ubuntugis-ubuntu-ppa-bionic.list
ubuntugis-ubuntu-ppa-bionic.list.save
ubuntugis-ubuntu-ubuntugis-unstable-bionic.list
ubuntugis-ubuntu-ubuntugis-unstable-bionic.list.save
我只是想拥有最新版本的QGIS和GRASS（由于Python3），现在我不知道该如何找回。有人有指针吗？
可能与您所做的没有太大不同：此处列出的说明似乎与Ubuntu 18.04完美配合：https://gis.stackexchange.com/questions/133033/installing-latest-qgis-version-on-ubuntu
sudo sh -c 'echo "deb http://qgis.org/debian bionic main" >> /etc/apt/sources.list'
wget -O - https://qgis.org/downloads/qgis-2019.gpg.key | gpg --import
gpg --fingerprint 51F523511C7028C3
gpg --export --armor 51F523511C7028C3 | sudo apt-key add -
几天前在这里https://askubuntu.com/questions/1207591/get-newer-version-of-qgis/1207664#1207664确认确认，>
并且我今天用新更新的Ubuntu 18.04进行了测试：请查看安装结果：qgis3_Ubuntu1804.txt→https://www.dropbox.com/s/1cw2z27h5q7sf51/qgis3_Ubuntu1804.txt?dl=0