# Pathlines plotting **URL:** \ **Category:** Uncategorized\ **Created:** [June 2, 2024, 4:31pm UTC](https://vapor.discourse.group/t/pathlines-plotting/382 "2024-06-02T16:31:09Z")\ **Posts on this page:** 9\ **Page:** 1
**Author:** ![elucy](https://avatars.discourse-cdn.com/v4/letter/e/85e7bf/32.png) [@elucy](https://vapor.discourse.group/u/elucy)\ **Post date:** [June 2, 2024, 4:31pm UTC](https://vapor.discourse.group/t/pathlines-plotting/382/1 "2024-06-02T16:31:09Z")
I’m trying to get pathlines to get parcel trajectories for a dataset that I’ve loaded into VAPOR. It has 6 time steps, but I don’t see anything appear when I try and plot the pathlines. I tried writing out the flow lines to a file, and when I look at the file there seems to be 899 rows, each at only the first time step in the dataset. I’ve attached some screenshots. I appreciate any help! ![Screen Shot 2024-05-30 at 4.07.38 PM](https://global.discourse-cdn.com/free1/uploads/vapor/original/1X/5547bc4c4c84926391237109493298ad16a1358d.jpeg) ![Screen Shot 2024-05-30 at 4.08.11 PM](https://global.discourse-cdn.com/free1/uploads/vapor/original/1X/b7f809cfb3ab897ed4bb62b22b05862edc79cc86.png) ![Screen Shot 2024-05-30 at 4.08.04 PM](https://global.discourse-cdn.com/free1/uploads/vapor/original/1X/c339f9932d4c21eb618e7b88ef48aa81ddbb737c.jpeg) Uploading: Screen Shot 2024-05-30 at 4.07.58 PM.png… Uploading: Screen Shot 2024-05-30 at 4.08.17 PM.png… ---
**Author:** ![sam](https://avatars.discourse-cdn.com/v4/letter/s/5f9b8f/32.png) [@sam](https://vapor.discourse.group/u/sam)\ **Post date:** [June 2, 2024, 4:32pm UTC](https://vapor.discourse.group/t/pathlines-plotting/382/2 "2024-06-02T16:32:42Z")
Hi @elucy , I wonder if you’re able to share the data set so we can investigate? Thanks! ---
**Author:** ![elucy](https://avatars.discourse-cdn.com/v4/letter/e/85e7bf/32.png) [@elucy](https://vapor.discourse.group/u/elucy)\ **Post date:** [June 4, 2024, 5:08pm UTC](https://vapor.discourse.group/t/pathlines-plotting/382/3 "2024-06-04T17:08:29Z")
Not sure that I can share the file on here. I can share the path to the file through NCAR: /glade/u/home/elucy/cm1out\_000901\_000906\_test.nc ---
**Author:** ![sam](https://avatars.discourse-cdn.com/v4/letter/s/5f9b8f/32.png) [@sam](https://vapor.discourse.group/u/sam)\ **Post date:** [June 4, 2024, 6:02pm UTC](https://vapor.discourse.group/t/pathlines-plotting/382/4 "2024-06-04T18:02:33Z")
Sounds good. Also, what format is this? NetCDF-CF compliant output? ---
**Author:** ![elucy](https://avatars.discourse-cdn.com/v4/letter/e/85e7bf/32.png) [@elucy](https://vapor.discourse.group/u/elucy)\ **Post date:** [June 4, 2024, 6:03pm UTC](https://vapor.discourse.group/t/pathlines-plotting/382/5 "2024-06-04T18:03:39Z")
Yes, it should be netCDF-CF compliant. ---
**Author:** ![pearse](https://yyz2.discourse-cdn.com/free1/user_avatar/vapor.discourse.group/pearse/32/177_2.png) [@pearse](https://vapor.discourse.group/u/pearse)\ **Post date:** [June 11, 2024, 9:03pm UTC](https://vapor.discourse.group/t/pathlines-plotting/382/6 "2024-06-11T21:03:11Z")
@elucy - I can see how this is misleading. For pathilines to render, VAPOR needs to advance in time. At timestep 0, no advection has taken place so nothing gets rendered. I’ve [filed a ticket](https://github.com/NCAR/VAPOR/issues/3622) to at least render something at the pathline point of origin to avoid this kind of confusion. If you have a github account, commenting on that issue would probably bump its priority. ---
**Author:** ![elucy](https://avatars.discourse-cdn.com/v4/letter/e/85e7bf/32.png) [@elucy](https://vapor.discourse.group/u/elucy)\ **Post date:** [June 11, 2024, 9:17pm UTC](https://vapor.discourse.group/t/pathlines-plotting/382/7 "2024-06-11T21:17:01Z")
I think I understand. So, is there an issue with my dataset itself then that’s keeping VAPOR from stepping through times? There should be 5 time steps there, but each time step is 1 second. ---
**Author:** ![pearse](https://yyz2.discourse-cdn.com/free1/user_avatar/vapor.discourse.group/pearse/32/177_2.png) [@pearse](https://vapor.discourse.group/u/pearse)\ **Post date:** [June 12, 2024, 1:56am UTC](https://vapor.discourse.group/t/pathlines-plotting/382/8 "2024-06-12T01:56:34Z")
No, nothing is wrong with your data. Just advance the timesteps using controls at the top of the GUI. I’d also recommend setting the “Pathline Length” parameter to 1, which you can see in the Seeding tab in the screenshot below. I’m rendering your data with pathlines at timestep 4. ![Screen Shot 2024-06-11 at 7.55.10 PM](https://global.discourse-cdn.com/free1/uploads/vapor/original/1X/5d7d467f1a0ceb287256f4c30ee0b32de9c4ece2.png) ---
**Author:** ![elucy](https://avatars.discourse-cdn.com/v4/letter/e/85e7bf/32.png) [@elucy](https://vapor.discourse.group/u/elucy)\ **Post date:** [June 14, 2024, 3:33pm UTC](https://vapor.discourse.group/t/pathlines-plotting/382/9 "2024-06-14T15:33:35Z")
Thank you, much appreciated!