我在 trusty 14.04.01 上使用 QGIS 时遇到问题。将我的机器从 precise 12.04 升级到 trusty 14.04 后，QGIS 从可用软件中消失了。我已自动删除它，并按照指示从 source.list 中删除了 PPA这里成功。但是，当我尝试运行新程序时，sudo apt-get install QGIS出现了以下依赖性错误，我有点卡在这里。
我运行 pgres 9.3 和 postGIS 2.2 没有任何问题，但是当我尝试安装 Qgis 时总是失败。
任何想法或解决方法都将受到赞赏！
在
Distributor ID: Ubuntu
Description: Ubuntu 14.04.1 LTS
Release: 14.04
Codename: trusty
错误：
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 to resolve the situation:
The following packages have unmet dependencies.
qgis : Depends: libgdal1h (>= 1.9.0) but it is not going to be installed
Depends: libqgis-analysis2.4.0 but it is not going to be installed
Depends: libqgis-core2.4.0 but it is not going to be installed
Depends: libqgis-gui2.4.0 but it is not going to be installed
Depends: libqgis-networkanalysis2.4.0 but it is not going to be installed
Depends: qgis-providers (= 2.4.0-0trusty3) but it is not going to be installed
Recommends: qgis-plugin-grass but it is not going to be installed
Recommends: qgis-plugin-globe but it is not going to be installed
Recommends: python-qgis but it is not going to be installed
E: Unable to correct problems, you have held broken packages.`
我的来源列表
# See http://help.ubuntu.com/community/UpgradeNotes for how to upgrade to
# newer versions of the distribution.
deb http://gb.archive.ubuntu.com/ubuntu/ trusty main restricted
deb-src http://gb.archive.ubuntu.com/ubuntu/ trusty main restricted
## Major bug fix updates produced after the final release of the
## distribution.
deb http://gb.archive.ubuntu.com/ubuntu/ trusty-updates main restricted
deb-src http://gb.archive.ubuntu.com/ubuntu/ trusty-updates main restricted
## N.B. software from this repository is ENTIRELY UNSUPPORTED by the Ubuntu
## team. Also, please note that software in universe WILL NOT receive any
## review or updates from the Ubuntu security team.
deb http://gb.archive.ubuntu.com/ubuntu/ trusty universe
deb-src http://gb.archive.ubuntu.com/ubuntu/ trusty universe
deb http://gb.archive.ubuntu.com/ubuntu/ trusty-updates universe
deb-src http://gb.archive.ubuntu.com/ubuntu/ trusty-updates universe
## N.B. software from this repository is ENTIRELY UNSUPPORTED by the Ubuntu
## team, and may not be under a free licence. Please satisfy yourself as to
## your rights to use the software. Also, please note that software in
## multiverse WILL NOT receive any review or updates from the Ubuntu
## security team.
deb http://gb.archive.ubuntu.com/ubuntu/ trusty multiverse
deb-src http://gb.archive.ubuntu.com/ubuntu/ trusty multiverse
deb http://gb.archive.ubuntu.com/ubuntu/ trusty-updates multiverse
deb-src http://gb.archive.ubuntu.com/ubuntu/ trusty-updates multiverse
## N.B. software from this repository may not have been tested as
## extensively as that contained in the main release, although it includes
## newer versions of some applications which may provide useful features.
## Also, please note that software in backports WILL NOT receive any review
## or updates from the Ubuntu security team.
deb http://gb.archive.ubuntu.com/ubuntu/ trusty-backports main restricted universe multiverse
deb-src http://gb.archive.ubuntu.com/ubuntu/ trusty-backports main restricted universe multiverse
deb http://security.ubuntu.com/ubuntu trusty-security main restricted
deb-src http://security.ubuntu.com/ubuntu trusty-security main restricted
deb http://security.ubuntu.com/ubuntu trusty-security universe
deb-src http://security.ubuntu.com/ubuntu trusty-security universe
deb http://security.ubuntu.com/ubuntu trusty-security multiverse
deb-src http://security.ubuntu.com/ubuntu trusty-security multiverse
## Uncomment the following two lines to add software from Canonical's
## 'partner' repository.
## This software is not part of Ubuntu, but is offered by Canonical and the
## respective vendors as a service to Ubuntu users.
# deb http://archive.canonical.com/ubuntu precise partner
# deb-src http://archive.canonical.com/ubuntu precise partner
## This software is not part of Ubuntu, but is offered by third-party
## developers who want to ship their latest software.
# deb http://extras.ubuntu.com/ubuntu trusty main
deb-src http://extras.ubuntu.com/ubuntu trusty main
deb http://archive.canonical.com/ trusty partner
deb-src http://archive.canonical.com/ trusty partner
deb http://apt.postgresql.org/pub/repos/apt/ precise-pgdg main # disabled on upgrade to trusty
#add qgis