Crosswalk crashing BenMAP

Hi all, I am getting an error when I try to create a new grid and create a crosswalk. Even using the example grid information on page 4-9 of the user manual gives me the error of “Object reference not set to an instance of an object,” and then BenMAP crashes. I have a windows 10 PC with the latest version of BenMAP. What could be causing this issue?

Hi Jordan,

I’m sorry to hear that you’re encountering this issue. Can you tell me what version of BenMAP-CE you’re using?

I am using version (July 25, 2018)

That’s a weird one, Jordan. I think we might need to set up a time to share screens, if that sounds ok. Please contact me at Fann dot Neal at Epa dot gov.

Neal, this sounds like it’s up my alley to diagnose the problem…

Jordan, I’d be more than happy to help.

Good news, I was able to replicate the problem so we don’t need to screen share. The bad news, I don’t know why there’s a problem… Let me try to figure out the source the problem, especially since it is in the user manual. The instructions may need to be updated with version changes.

In the meantime, there are other exercises on the BenMAP website you can follow along with to get familiar with the program. Just keep in mind there may be some slight differences with what you see on your screen and what’s in the steps, but it shouldn’t be a show stopper like this issue.

Thank you for your responses! I’m glad it’s not just me having the issue.

I am having what might be a similar problem.
I have done several successful analyses all on the grid of local govt areas, but have recently created another grid of health districts. There are 128 LGAs but only 16 health districts, and nearly all the LGAs sit neatly within health districts. I created cross walks when I introduced the second map to the setup.
Now when I use incidence at the health district level and population at the LGA level I get an error message:
at System.ling.enumerable.ToList[Tsource](lEnumerable’1 source) at BenMAP.HealthImpactFunctions,btnRun_Click(Object sender. EventArgs e)

Do you know what this means?
Ben Ewald

Sorry everyone, I still haven’t been able to find the source of the error. We definitely see the value in allowing BenMAP users to generate their own grids within the program, especially those who may not have access to GIS software, so we will elevate this up quickly and try to find a fix for this problem. Once we resolve it, I can work up a short write-up with the correct steps to generate a grid and post it on our website. Thank you for your patience.

Has anyone tried clearing the existing crosswalks and then trying to build new crosswalks? In version 1.4.x, this can be accomplished by navigating to tools–>compute grid crosswalks. See screen shot below.

Neal, I just tried clearing the crosswalks and then running my crosswalk, but unfortunately still encounter the same error.

Just to follow up on my post from 1st September, I exported my air surface to Excel and completed the analysis there, replicating what BenMap does in the Excel environment. Its slower, but I feel I have more control and can see every step. This was possible because the geography of my two maps had every small area fitting neatly into each bigger area. It would not be possible between a square grid and a map of administrative boundaries where the cross walks would be more complex.

Thanks for the update Ben!