I installed ros melodic few weeks ago.. i got "" when I executed rosversion ros then.. now Im getting "Cannot locate ros" when I execute that. Also when i use these commands roslaunch and roscore,it asks me to install them and when i try installing, it replies me with you have held broken packages
addy21000@addy-PC:~$ rosversion ros
Cannot locate [ros]
addy21000@addy-PC:~$ dpkg -l | grep ros-melodic-roslaunch
addy21000@addy-PC:~$ dpkg -l | grep ros-melodic-roslaunch
output of dpkg -l | grep ros-melodic-roslaunch
no output,it just executed
output of ls -al /opt/ros/melodic
total 100 drwxr-xr-x 7 root root 4096 Mar 22 16:35 . drwxr-xr-x 3 root root 4096 Mar 11 17:27 .. drwxr-xr-x 2 root root 4096 Apr 4 18:05 bin -rw-r--r-- 1 root root 0 Mar 3 10:27 .catkin -rwxr-xr-x 1 root root 506 Mar 3 10:27 env.sh drwxr-xr-x 4 root root 4096 Mar 11 17:27 etc drwxr-xr-x 48 root root 4096 Apr 6 18:47 include drwxr-xr-x 22 root root 20480 Apr 4 18:05 lib -rw-r--r-- 1 root root 283 Mar 3 10:27 local_setup.bash -rw-r--r-- 1 root root 347 Mar 3 10:27 local_setup.sh -rw-r--r-- 1 root root 293 Mar 3 10:27 local_setup.zsh -rw-r--r-- 1 root root 56 Mar 3 10:27 .rosinstall -rw-r--r-- 1 root root 260 Mar 3 10:27 setup.bash -rw-r--r-- 1 root root 2774 Mar 3 10:27 setup.sh -rwxr-xr-x 1 root root 13310 Mar 3 10:27 _setup_util.py -rw-r--r-- 1 root root 270 Mar 3 10:27 setup.zsh drwxr-xr-x 92 root root 12288 Apr 6 18:48 share
output of ls -al /opt/ros/melodic/bin
total 580 drwxr-xr-x 2 root root 4096 Apr 4 18:05 . drwxr-xr-x 7 root root 4096 Mar 22 16:35 .. -rwxr-xr-x 1 root root 2807 Mar 3 10:27 catkin_find -rwxr-xr-x 1 root root 1086 Mar 3 10:27 catkin_init_workspace -rwxr-xr-x 1 root root 15224 Mar 3 10:27 catkin_make -rwxr-xr-x 1 root root 8239 Mar 3 10:27 catkin_make_isolated -rwxr-xr-x 1 root root 1889 Mar 3 10:27 catkin_test_results -rwxr-xr-x 1 root root 2416 Mar 3 10:27 catkin_topological_order -rwxr-xr-x 1 root root 1663 Mar 3 10:32 rosboost-cfg -rwxr-xr-x 1 root root 1664 Mar 3 10:32 rosclean -rwxr-xr-x 1 root root 1760 Mar 20 15:41 rosgraph -rwxr-xr-x 1 root root 2668 Mar 3 11:02 rosmake -rwxr-xr-x 1 root root 1667 Mar 20 15:45 rosmaster -rwxr-xr-x 1 root root 1659 Mar 20 15:48 rosparam -rwxr-xr-x 1 root root 255 Mar 11 05:49 rqt -rwxr-xr-x 1 root root 30904 Mar 20 16:54 run_selftest -rwxr-xr-x 1 root root 149848 Mar 20 16:54 selftest_example -rwxr-xr-x 1 root root 313536 Mar 20 16:54 selftest_rostest -rwxr-xr-x 1 root root 10512 Mar 3 11:09 stage
output of
grep remove /var/log/dpkg.log
2020-04-04 18:04:03 startup packages remove
2020-04-04 18:04:03 remove ros-melodic-desktop-full:amd64 1.4.1-0bionic.20200320.170844 <none> 2020-04-04 18:04:04 remove ros-melodic-perception:amd64 1.4.1-0bionic.20200320.161440 <none> 2020-04-04 18:04:05 remove ros-melodic-desktop:amd64 1.4.1-0bionic.20200320.165834 <none> 2020-04-04 18:04:05 remove ros-melodic-viz:amd64 1.4.1-0bionic.20200320.155640 <none> 2020-04-04 18:04:06 remove ros-melodic-geometry-tutorials:amd64 0.2.2-0bionic.20200320.154702 <none> 2020-04-04 18:04:06 remove ros-melodic-turtle-tf2:amd64 0.2.2-0bionic.20200320.123541 <none> 2020-04-04 18:04:07 remove ros-melodic-common-tutorials:amd64 0.1.11-0bionic.20200320.124359 <none> 2020-04-04 18:04:08 remove ros-melodic-turtle-actionlib:amd64 0.1.11-0bionic.20200320.123504 <none> 2020-04-04 18:04:08 remove ros-melodic-turtle-tf:amd64 0.2.2-0bionic.20200320.145720 <none> 2020-04-04 18:04:09 remove ros-melodic-actionlib-tutorials:amd64 0.1.11-0bionic.20200320.123237 <none> 2020-04-04 18:04:09 remove ros-melodic-simulators:amd64 1.4.1-0bionic.20200320.164211 <none> 2020-04-04 18:04:10 remove ros-melodic-robot:amd64 1.4.1-0bionic.20200320.163604 <none> 2020-04-04 18:04:10 remove ros-melodic-diagnostics:amd64 1.9.3-0bionic.20200320.153909 <none> 2020-04-04 18:04:11 remove ros-melodic-diagnostic-aggregator:amd64 1.9.3-0bionic.20200320.111850 <none> 2020-04-04 18:04:11 remove ros-melodic-image-pipeline:amd64 1.14.0-1bionic.20200320.155605 <none> 2020-04-04 18:04:12 remove ros-melodic-camera-calibration:amd64 1.14.0-1bionic.20200320.141115 <none> 2020-04-04 18:04:12 remove ros-melodic-image-publisher:amd64 1.14.0-1bionic.20200320.134551 <none> 2020-04-04 18:04:13 remove ros-melodic-image-common:amd64 1.11.13-0bionic.20200320.141440 <none> 2020-04-04 18:04:13 remove ros-melodic-image-transport-plugins:amd64 1.9.5-0bionic.20200320.155634 <none> 2020-04-04 18:04:14 remove ros-melodic-compressed-depth-image-transport:amd64 1.9.5-0bionic.20200320.141515 <none> 2020-04-04 18:04:14 remove ros-melodic-compressed-image-transport:amd64 1.9.5-0bionic.20200320.141529 <none> 2020-04-04 18:04:15 remove ros-melodic-urdf-sim-tutorial:amd64 0.4.0-0bionic.20200320.154215 <none> 2020-04-04 18:04:15 remove ros-melodic-gazebo-ros-control:amd64 2.8.6-1bionic.20200320.144157 <none> 2020-04-04 18:04:16 remove ros-melodic-control-toolbox:amd64 1.17.0-0bionic.20200320.131747 <none> 2020-04-04 18:04:16 remove ros-melodic-controller-manager:amd64 0.17.0-1bionic.20200320.133159 <none> 2020-04-04 18:04:17 remove ros-melodic-controller-manager-msgs:amd64 0.17.0-1bionic.20200320.132558 <none> 2020-04-04 18:04:18 remove ros-melodic-depth-image-proc:amd64 1.14.0-1bionic.20200320.141910 <none> 2020-04-04 18:04:18 remove ros-melodic-diagnostic-analysis:amd64 1.9.3-0bionic.20200320.122626 <none> 2020-04-04 18:04:19 remove ros-melodic-diagnostic-common-diagnostics:amd64 1.9.3-0bionic.20200320.151240 <none> 2020-04-04 18:04:19 remove ros-melodic-diff-drive-controller:amd64 0.15.1-1bionic.20200320.152047 <none> 2020-04-04 18:04:20 remove ros-melodic-theora-image-transport:amd64 1.9.5-0bionic.20200320.135349 <none> 2020-04-04 18:04:20 remove ros-melodic-stereo-image-proc:amd64 1.14.0-1bionic.20200320.141859 <none> 2020-04-04 18:04:21 remove ros-melodic-executive-smach:amd64 2.0.1-0bionic.20200320.140009 <none> 2020-04-04 18:04:21 remove ros-melodic-laser-pipeline:amd64 1.6.3-0bionic.20200320.160847 <none> 2020-04-04 18:04:22 remove ros-melodic-laser-filters:amd64 1.8.8-1bionic.20200320.144320 <none> 2020-04-04 18:04:22 remove ros-melodic-laser-assembler:amd64 1.7.7-2bionic.20200320.144308 <none> 2020-04-04 18:04:23 remove ros-melodic-filters:amd64 1.8.1-0bionic.20200320.112037 <none> 2020-04-04 18:04:23 remove ros-melodic-position-controllers:amd64 0.15.1-1bionic.20200320.124659 <none> 2020-04-04 18:04:24 remove ros-melodic-forward-command-controller:amd64 0.15.1-1bionic.20200320.123949 <none> 2020-04-04 18:04:24 remove ros-melodic-gazebo-ros-pkgs:amd64 2.8.6-1bionic.20200320.155719 <none> 2020-04-04 18:04:25 remove ros-melodic-gazebo-plugins:amd64 2.8.6-1bionic.20200320.144150 <none> 2020-04-04 18:04:25 remove ros-melodic-gazebo-ros:amd64 2.8.6-1bionic.20200320.143226 <none> 2020-04-04 18:04:26 remove ros-melodic-geometry:amd64 1.12.1-1bionic.20200320.162934 <none> 2020-04-04 18:04:26 remove ros-melodic-image-proc:amd64 1.14.0-1bionic.20200320.141055 <none> 2020-04-04 18:04:27 remove ros-melodic-image-rotate:amd64 1.14.0-1bionic.20200320.134642 <none> 2020-04-04 18:04:27 remove ros-melodic-urdf-tutorial:amd64 0.4.0-0bionic.20200320.153349 <none> 2020-04-04 18:04:28 remove ros-melodic-rqt-common-plugins:amd64 0.4.8-0bionic.20200320.135753 <none> 2020-04-04 18:04:28 remove ros-melodic-rqt-image-view:amd64 0.4.14-1bionic.20200320.135036 <none> 2020-04-04 18:04:29 remove ros-melodic-image-view:amd64 1.14.0-1bionic.20200320.141834 <none> 2020-04-04 18:04:30 remove ros-melodic-visualization-tutorials:amd64 0.10.3-0bionic.20200320.165034 <none> 2020-04-04 18:04:31 remove ros-melodic-interactive-marker-tutorials:amd64 0.10.3-0bionic.20200320.150349 <none> 2020-04-04 18:04:31 remove ros-melodic-joint-limits-interface:amd64 0.17.0-1bionic.20200320.112629 <none> 2020-04-04 18:04:32 remove ros-melodic-joint-state-controller:amd64 0.15.1-1bionic.20200320.130100 <none> 2020-04-04 18:04:32 remove ros-melodic-joint-state-publisher:amd64 1.12.15-1bionic.20200320.132142 <none> 2020-04-04 18:04:33 remove ros-melodic-robot-state-publisher:amd64 1.14.0-1bionic.20200320.143659 <none> 2020-04-04 18:04:33 remove ros-melodic-kdl-parser:amd64 1.13.1-0bionic.20200320.112606 <none> 2020-04-04 18:04:34 remove ros-melodic-kdl-parser-py:amd64 1.13.1-0bionic.20200320.112722 <none> 2020-04-04 18:04:34 remove ros-melodic-librviz-tutorial:amd64 0.10.3-0bionic.20200320.152741 <none> 2020-04-04 18:04:35 remove ros-melodic-rqt-robot-plugins:amd64 0.5.7-0bionic.20200320.154140 <none> 2020-04-04 18:04:35 remove ros-melodic-rqt-rviz:amd64 0.6.0-0bionic.20200320.153027 <none> 2020-04-04 18:04:36 remove ros-melodic-rqt-gui-cpp:amd64 0.5.1-1bionic.20200320.110243 <none> 2020-04-04 18:04:36 remove ros-melodic-perception-pcl:amd64 1.7.0-2bionic.20200320.155831 <none> 2020-04-04 18:04:37 remove ros-melodic-pcl-ros:amd64 1.7.0-2bionic.20200320.143546 <none> 2020-04-04 18:04:38 remove ros-melodic-nodelet-tutorial-math:amd64 0.1.11-0bionic.20200320.110238 <none> 2020-04-04 18:04:38 remove ros-melodic-qt-gui-cpp:amd64 0.4.0-1bionic.20200304.013951 <none> 2020-04-04 18:04:39 remove ros-melodic-pluginlib-tutorials:amd64 0.1.11-0bionic.20200320.103726 <none> 2020-04-04 18:04:39 remove ros-melodic-polled-camera:amd64 1.11.13-0bionic.20200320.130902 <none> 2020-04-04 18:04:40 remove ros-melodic-realtime-tools:amd64 1.15.1-1bionic.20200320.123324 <none> 2020-04-04 18:04:40 remove ros-melodic-ros-tutorials:amd64 0.9.2-1bionic.20200320.112805 <none> 2020-04-04 18:04:41 remove ros-melodic-rqt-action:amd64 0.4.9-0bionic.20200320.133350 <none> 2020-04-04 18:04:41 remove ros-melodic-rqt-service-caller:amd64 0.4.8-0bionic.20200320.133802 <none> 2020-04-04 18:04:42 remove ros-melodic-rqt-bag-plugins:amd64 0.4.12-0bionic.20200320.132308 <none> 2020-04-04 18:04:43 remove ros-melodic-xacro:amd64 1.13.5-1bionic.20200320.112842 <none> 2020-04-04 18:04:43 remove ros-melodic-rqt-launch:amd64 0.4.8-0bionic.20200320.133248 <none> 2020-04-04 18:04:44 remove ros-melodic-rqt-publisher:amd64 0.4.8-0bionic.20200320.133758 <none> 2020-04-04 18:04:44 remove ros-melodic-rqt-srv:amd64 0.4.8-0bionic.20200320.133359 <none> 2020-04-04 18:04:45 remove ros-melodic-rqt-moveit:amd64 0.5.7-0bionic.20200320.132451 <none> 2020-04-04 18:04:45 remove ros-melodic-rqt-robot-dashboard:amd64 0.5.7-0bionic.20200320.151825 <none> 2020-04-04 18:04:46 remove ros-melodic-urdfdom-py:amd64 0.4.2-1bionic.20200320.110813 <none> 2020-04-04 18:04:46 remove ros-melodic-rospy-tutorials:amd64 0.9.2-1bionic.20200320.112352 <none> 2020-04-04 18:04:47 remove ros-melodic-rqt-tf-tree:amd64 0.6.0-0bionic.20200320.132545 <none> 2020-04-04 18:04:48 remove ros-melodic-smach-ros:amd64 2.0.1-0bionic.20200320.123218 <none> 2020-04-04 18:04:48 remove ros-melodic-rqt-topic:amd64 0.4.11-1bionic.20200320.122544 <none> 2020-04-04 18:04:49 remove ros-melodic-rqt-robot-monitor:amd64 0.5.9-1bionic.20200320.123802 <none> 2020-04-04 18:04:49 remove ros-melodic-rqt-bag:amd64 0.4.12-0bionic.20200320.122409 <none> 2020-04-04 18:04:50 remove ros-melodic-rqt-reconfigure:amd64 0.5.1-1bionic.20200320.133315 <none> 2020-04-04 18:04:50 remove ros-melodic-rqt-dep:amd64 0.4.9-0bionic.20200320.133806 <none> 2020-04-04 18:04:51 remove ros-melodic-rqt-web:amd64 0.4.8-0bionic.20200320.111245 <none> 2020-04-04 18:04:51 remove ros-melodic-rqt-top:amd64 0.4.8-0bionic.20200320.111236 <none> 2020-04-04 18:04:52 remove ros-melodic-rqt-msg:amd64 0.4.8-0bionic.20200320.133304 <none> 2020-04-04 18:04:53 remove ros-melodic-rqt-nav-view:amd64 0.5.7-0bionic.20200320.151342 <none> 2020-04-04 18:04:53 remove ros-melodic-rqt-plot:amd64 0.4.9-0bionic.20200320.123751 <none> 2020-04-04 18:04:54 remove ros-melodic-rqt-pose-view:amd64 0.5.8-0bionic.20200320.151355 <none> 2020-04-04 18:04:54 remove ros-melodic-rqt-py-console:amd64 0.4.8-0bionic.20200320.111235 <none> 2020-04-04 18:04:55 remove ros-melodic-rqt-robot-steering:amd64 0.5.10-1bionic.20200320.122539 <none> 2020-04-04 18:04:55 remove ros-melodic-rqt-runtime-monitor:amd64 0.5.7-0bionic.20200320.111221 <none> 2020-04-04 18:04:56 remove ros-melodic-rqt-shell:amd64 0.4.9-0bionic.20200320.111324 <none> 2020-04-04 18:04:56 remove ros-melodic-rviz-plugin-tutorials:amd64 0.10.3-0bionic.20200320.164154 <none> 2020-04-04 18:04:57 remove ros-melodic-rviz-python-tutorial:amd64 0.10.3-0bionic.20200320.164204 <none> 2020-04-04 18:04:57 remove ros-melodic-stage-ros:amd64 1.8.0-0bionic.20200320.143727 <none> 2020-04-04 18:04:58 remove ros-melodic-tf-conversions:amd64 1.12.1-1bionic.20200320.160712 <none> 2020-04-04 18:04:59 remove ros-melodic-tf2-geometry-msgs:amd64 0.6.5-0bionic.20200320.124157 <none> 2020-04-04 18:04:59 remove ros-melodic-tf2-kdl:amd64 0.6.5-0bionic.20200320.124204 <none> 2020-04-04 18:05:00 remove ros-melodic-transmission-interface:amd64 0.17.0-1bionic.20200320.104238 <none> 2020-04-04 18:05:00 remove ros-melodic-ros-base:amd64 1.4.1-0bionic.20200320.142754 <none> 2020-04-04 18:05:01 remove ros-melodic-ros-core:amd64 1.4.1-0bionic.20200320.142331 <none> 2020-04-04 18:05:01 remove ros-melodic-ros-comm:amd64 1.14.5-1bionic.20200320.130835 <none> 2020-04-04 18:05:02 remove ros-melodic-roslisp:amd64 1.9.24-1bionic.20200304.012725 <none> 2020-04-04 18:05:02 remove ros-melodic-turtlesim:amd64 0.9.2-1bionic.20200320.103649 <none> 2020-04-04 18:05:03 remove ros-melodic-bond-core:amd64 1.8.3-0bionic.20200320.110212 <none> 2020-04-04 18:05:04 remove ros-melodic-bondpy:amd64 1.8.3-0bionic.20200320.105628 <none> 2020-04-04 18:05:05 remove ros-melodic-camera-info-manager:amd64 1.11.13-0bionic.20200320.131644 <none> 2020-04-04 18:05:05 remove ros-melodic-rviz:amd64 1.13.7-1bionic.20200320.145803 <none> 2020-04-04 18:05:06 remove ros-melodic-image-transport:amd64 1.11.13-0bionic.20200320.130043 <none> 2020-04-04 18:05:06 remove ros-melodic-interactive-markers:amd64 1.11.4-0bionic.20200320.145229 <none> 2020-04-04 18:05:07 remove ros-melodic-laser-geometry:amd64 1.6.4-0bionic.20200320.143503 <none> 2020-04-04 18:05:07 remove ros-melodic-ros:amd64 1.14.8-1bionic.20200304.012218 <none> 2020-04-04 18:05:08 remove ros-melodic-mk:amd64 1.14.8-1bionic.20200304.002810 <none> 2020-04-04 18:05:09 remove ros-melodic-nodelet-core:amd64 1.9.16-0bionic.20200320.132703 <none> 2020-04-04 18:05:09 remove ros-melodic-nodelet-topic-tools:amd64 1.9.16-0bionic.20200320.131845 <none> 2020-04-04 18:05:10 remove ros-melodic-urdf:amd64 1.13.2-1bionic.20200320.112052 <none> 2020-04-04 18:05:10 remove ros-melodic-resource-retriever:amd64 1.12.6-1bionic.20200304.012919 <none> 2020-04-04 18:05:11 remove ros-melodic-rosbash:amd64 1.14.8-1bionic.20200303.063937 <none> 2020-04-04 18:05:12 remove ros-melodic-roscreate:amd64 1.14.8-1bionic.20200303.064345 <none> 2020-04-04 18:05:12 remove ros-melodic-rqt-console:amd64 0.4.9-1bionic.20200320.133159 <none> 2020-04-04 18:05:13 remove ros-melodic-rqt-logger-level:amd64 0.4.8-0bionic.20200320.132346 <none> 2020-04-04 18:05:13 remove ros-melodic-rqt-graph:amd64 0.4.11-1bionic.20200320.130158 <none> 2020-04-04 18:05:14 remove ros-melodic-rqt-gui-py:amd64 0.5.1-1bionic.20200320.110645 <none> 2020-04-04 18:05:15 remove ros-melodic-tf:amd64 1.12.1-1bionic.20200320.142044 <none> 2020-04-04 18:05:15 remove ros-melodic-tf2-ros:amd64 0.6.5-0bionic.20200320.123006 <none> 2020-04-04 18:05:16 remove ros-melodic-dynamic-reconfigure:amd64 1.6.3-1bionic.20200320.131158 <none> 2020-04-04 18:05:17 remove ros-melodic-nodelet:amd64 1.9.16-0bionic.20200320.105613 <none> 2020-04-04 18:05:17 remove ros-melodic-rqt-py-common:amd64 0.5.1-1bionic.20200320.123218 <none> 2020-04-04 18:05:18 remove ros-melodic-tf2-py:amd64 0.6.5-0bionic.20200320.105600 <none> 2020-04-04 18:05:19 remove ros-melodic-roswtf:amd64 1.14.5-1bionic.20200320.130212 <none> 2020-04-04 18:05:20 remove ros-melodic-actionlib:amd64 1.12.0-1bionic.20200320.122357 <none> 2020-04-04 18:05:21 remove ros-melodic-rosnode:amd64 1.14.5-1bionic.20200320.121954 <none> 2020-04-04 18:05:22 remove ros-melodic-rosservice:amd64 1.14.5-1bionic.20200320.125815 <none> 2020-04-04 18:05:23 remove ros-melodic-rostest:amd64 1.14.5-1bionic.20200320.111356 <none> 2020-04-04 18:05:24 remove ros-melodic-rostopic:amd64 1.14.5-1bionic.20200320.121530 <none> 2020-04-04 18:05:25 remove ros-melodic-roslaunch:amd64 1.14.5-1bionic.20200320.110824 <none> 2020-04-04 18:05:25 remove ros-melodic-rosmsg:amd64 1.14.5-1bionic.20200320.125233 <none> 2020-04-04 18:05:26 remove ros-melodic-rosunit:amd64 1.14.8-1bionic.20200303.064408 <none> 2020-04-04 18:05:26 remove ros-melodic-rosbag:amd64 1.14.5-1bionic.20200320.113710 <none> 2020-04-04 18:05:27 remove ros-melodic-rosbag-storage:amd64 1.14.5-1bionic.20200320.113139 <none> 2020-04-04 18:05:28 remove ros-melodic-rospy:amd64 1.14.5-1bionic.20200320.104032 <none> 2020-04-04 18:05:28 remove ros-melodic-pluginlib:amd64 1.12.1-0bionic.20200304.012909 <none> 2020-04-04 18:05:29 remove ros-melodic-roslib:amd64 1.14.8-1bionic.20200303.063927 <none> 2020-04-04 18:05:30 remove ros-melodic-rospack:amd64 2.5.5-1bionic.20200303.063336 <none> 2020-04-04 18:05:30 remove python-rosdep-modules:all 0.18.0-1 <none> 2020-04-06 18:47:19 startup packages remove 2020-04-06 18:47:53 remove ros-melodic-pcl-conversions:amd64 1.7.0-2bionic.20200320.141600 <none> 2020-04-06 18:47:54 remove libpcl-dev:amd64 1.8.1+dfsg1-2ubuntu2.18.04.1 <none> 2020-04-06 18:47:57 remove libvtk6-qt-dev:amd64 6.3.0+dfsg1-11build1 <none> 2020-04-06 18:47:59 remove libvtk6-dev:amd64 6.3.0+dfsg1-11build1 <none> 2020-04-06 18:48:00 remove python-vtk6:amd64 6.3.0+dfsg1-11build1 <none> 2020-04-06 18:48:05 remove python-autobahn:all 17.10.1+dfsg1-2 <none> 2020-04-06 18:48:06 remove python-txaio:all 2.8.1-1 <none> 2020-04-06 18:48:07 remove python-twisted:all 17.9.0-2ubuntu0.1 <none> 2020-04-06 18:48:08 remove python-twisted-core:all 17.9.0-2ubuntu0.1 <none> 2020-04-06 18:48:11 remove python-service-identity:all 16.0.0-2 <none> 2020-04-06 18:48:12 remove python-pyasn1-modules:all 0.2.1-0.2 <none> 2020-04-06 18:48:13 remove ros-melodic-cmake-modules:amd64 0.4.2-0bionic.20200303.062545 <none> 2020-04-07 15:38:51 startup packages remove 2020-04-07 15:38:52 remove python-rosdep2:all 0.11.8-1 <none>
output of dpkg -l | grep ros-melodic-roslaunch
ii ros-melodic-roslaunch 1.14.5-1bionic.20200320.110824 amd64 roslaunch is a tool for easily launching multiple ROS nodes locally and remotely via SSH, as well as setting parameters on the Parameter Server.
Originally posted by Addy on ROS Answers with karma: 3 on 2020-04-07
Post score: 0
Original comments
Comment by Addy on 2020-04-07:
should i reinstall ros?
Comment by gvdhoorn on 2020-04-07:
Have you remembered to source /opt/ros/melodic/setup.bash before trying to run those commands?
And:
Also when i use these commands roslaunch and roscore,it asks me to install them and when i try installing, it replies me with you have held broken packages
Yes. Do not install those packages, unless you are more experienced. See UpstreamPackages for more information.
Comment by Addy on 2020-04-07:
yes i did this source /opt/ros/melodic/setup.bash
Comment by gvdhoorn on 2020-04-07:
Then please show us the exact command sequence and output of those commands in a verbatim copy of the terminal in which you try to do this. Do not post or link to screenshots.
And please include the output of dpkg -l | grep ros-melodic-roslaunch as well.
Use the edit button/link to update your question.
Comment by Addy on 2020-04-07:
no output.
Comment by gvdhoorn on 2020-04-07:
And you did install ROS using apt before?
If so, it would seem somehow you've managed to uninstall it all / at least roslaunch.
What is the output of ls -al /opt/ros/melodic/bin? And perhaps also of ls -al /opt/ros/melodic itself?
it might also be informative to see what grep remove /var/log/dpkg.log returns.
Comment by gvdhoorn on 2020-04-07:\
bro @gvdhoorn..i think i did what you asked for.Please reply:)
I'm not your "bro", and this is not a chat platform.
It's a forum, and this is not my job.
Please refrain from calling people out by name like that.
Comment by Addy on 2020-04-07:
yes i used apt to install ros
Comment by gvdhoorn on 2020-04-07:
Where is the output of grep remove /var/log/dpkg.log?
Comment by Addy on 2020-04-07:
I'm sorry about that.I'm in desperate need of help.I meant to no offense.
