Migration status

Although the new site is live, work is still in progress to improve it.

Known issues:

  1. Forums: The organization of (sub-)categories and threads is disrupted. Please use the search box inside the "Message boards" to navigate.

Message Boards

RE: Bug with progress bar and increase raster cell size?

ND
Noud Dijkema, modified 26 Days ago.

Bug with progress bar and increase raster cell size?

Youngling Posts: 7 Join Date: 11/20/19 Recent Posts
Hi all,
When making an IDF describing my BND, the cell sizes were too fine for my goal. I increased the cellsizes with the use of GridRefinement to 25m to reduce the computational load when running my model. This was done by drawing one big rectangle over all of the cells containing data. When then new IDF was created, it was loaded in the iMod Manager and a progress bar for drawing the bitmap can be seen in the bottom of iMod. This loading bar was bugged, as it was loading over 100% and needed to load more than 1 time (when it finished at a random number above 100% it would start over again). In the end it would display the IDF, but the IDF with the new cell sizes actually takes longer to load. Will this also reduce the speed of  running my model? Also, why is the loading time increased even though there are fewer cells? I'd like to mention that iMod 5.0 was used to create a TOP layer, which was then edited to be the BND.IDf, which was done in iMod 5.1.

Next to this I'd like to mention something else I encountered with loading bars. There was also an IDF made from a GEN file containing over 8000 GENs. When the GENs are loaded and the process is started, there is again a progress bar but for this amount of GENs it is not useful anymore. Instead of showing the total progress of making the IDF, it would show the progress of turning 1 GEN into a part of the IDF. I added the following files in case you want to recreate what I did:

DrainageKoudeVaart.GEN
100+loadingbar.png

The IDF's are too big to share on this forum, please contact me if you require those so I can share them with you through a different method.

Kind regards,

Noud Dijkema
Frans Roelofsen, modified 20 Days ago.

RE: Bug with progress bar and increase raster cell size?

Padawan Posts: 99 Join Date: 11/11/13 Recent Posts
Hi Noud, Please share your IDF so we can reproduce your issue.
You describe the upscaling by "This was done by drawing one big rectangle over all of the cells containing data".
--> Can you explane the steps a bit more? What do you mean with the reactangle. 
I would for instance select the 'old' IDF in the iMOD Manger, go to MAP > IDF-options > IDF-calculate and choose tab 2 "scale/size" and use the extend Map A. Kind regards, 
ND
Noud Dijkema, modified 20 Days ago.

RE: Bug with progress bar and increase raster cell size?

Youngling Posts: 7 Join Date: 11/20/19 Recent Posts
Hi Frans,

I added the IDF's as BND.rar, this contains both the Fine (unaltered) ande the Coarse IDF.

I was unaware that the IDF could be scaled this way, I used the following method:
Rightclick IDF after loading it in the iMod manager-> IDF options -> IDF edit -> 2nd tab GridRefinement -> draw a rectangle covering the entire area of my IDF and enter 25 as the new cellsize in the Enter Value box
Frans Roelofsen, modified 14 Days ago.

RE: Bug with progress bar and increase raster cell size?

Padawan Posts: 99 Join Date: 11/11/13 Recent Posts
Hi Noud, Thanks for your IDF file. I found out what causes the behavior you experience.I loaded your coarse IDF file into iMOD.  In the iMOD Manger I clicked the "i" button (properties) and found out that the IDF contains cells with cell sizes (DX and DY) ranging from 0.5 tot 25m. Than I understood that your IDF had become a non equidistant IDF. So you selected a (large) part of the fine IDF and upscaled only that selected cells to coarse cells. So it became an IDF with a course center and a fine boundary. You can see that in the screendump I attached. There I displayed the IDF with the rasterlines printed. 
Displaying this IDF takes a lot of time. Reason is that iMOD in case of a non equidistance grid will plot each cell, so the highest resolution. In case of a equidistant IDF that is fine, iMOD will only display with a lower accuracy. You can see it in the lower bar of iMOD: if I zoom to the full extent of BNDFine.IDF the accuracy is X:62/Y:62.  I will check what causes the error in the loading bar.
 This file will not slow down iMODFLOW significantly while this boundary IDF is only read once at the start of your modelrun. However, in case you run a transient model where each stress period a non equidistant IDF is read (e.g. river stage) the total runtime will be influenced. So again: use IDF calc (in GUI or iMOD batch) to upscale an IDF as a whole, keep your IDF's equidistant. Kind regards, Frans
ND
Noud Dijkema, modified 13 Days ago.

RE: Bug with progress bar and increase raster cell size?

Youngling Posts: 7 Join Date: 11/20/19 Recent Posts
Hi Frans,

Thank you for your elaborate answer, it is now clear to me what I did wrong. In the meantime I used the method earlier proposed by you and these files work perfectly for my transient model.

Kind regards,

Noud