# MEGAN v3.2 cantype preprocessor error

**URL:** <https://forum.cmascenter.org/t/megan-v3-2-cantype-preprocessor-error/5311>\
**Category:** MEGAN\
**Created:** [October 25, 2024, 10:01am UTC](https://forum.cmascenter.org/t/megan-v3-2-cantype-preprocessor-error/5311 "2024-10-25T10:01:38Z")\
**Posts on this page:** 2\
**Page:** 1

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**Author:** ![kanaboo](https://avatars.discourse-cdn.com/v4/letter/k/df788c/32.png) [@kanaboo](https://forum.cmascenter.org/u/kanaboo)\
**Post date:** [October 25, 2024, 10:01am UTC](https://forum.cmascenter.org/t/megan-v3-2-cantype-preprocessor-error/5311/1 "2024-10-25T10:01:38Z")

</div>

Hi all,  
I have some problems when running the cantype MEGANv3.2 preprocessor (compiled by ifort).  
Other preprocessors (e.g. lai, ecotype, landtype etc.) has successfully created the .csv file I want. But the cantype preprocessor stopped in the middle of the processing with showing **forrtl: severe (174): SIGSEGV, segmentation fault occurred**.

 ![image](https://canada1.discourse-cdn.com/flex027/uploads/cmas/original/2X/4/4c0cc3ffea89627ae2a70b26a99c17bacce798e5.png)

I have tried all suggestions form [https://www.intel.com/content/www/us/en/developer/articles/troubleshooting/determining-root-cause-of-sigsegv-or-sigbus-errors.html](https://www.intel.com/content/www/us/en/developer/articles/troubleshooting/determining-root-cause-of-sigsegv-or-sigbus-errors.html)  
but none of them work. I wonder if there are any suggestions?  
Thank you.

---

<div class="post-metadata">

**Author:** ![willison.jeff](https://avatars.discourse-cdn.com/v4/letter/w/c89c15/32.png) [@willison.jeff](https://forum.cmascenter.org/u/willison.jeff)\
**Post date:** [October 25, 2024, 2:30pm UTC](https://forum.cmascenter.org/t/megan-v3-2-cantype-preprocessor-error/5311/2 "2024-10-25T14:30:16Z")

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Looks like it’s failing on the tree file. What does the tree section of your prepmegan4cmaq.cantype.inp namelist look like? Is it consistent with the input?

For example, my .inp file:

```
 treefilename = 'GF3aTree.nc'
 treevarname = 'm20tree'
 treefillvalue = '-128'

```

And the input file I’m using:

> ncdump -h …/GF3aTree.nc | more

```
 netcdf GF3aTree {
 dimensions:
    lon = 43200 ;
    lat = 16800 ;
  variables:
    double lon(lon) ;
            lon:long_name = "longitude coordinate" ;
            lon:standard_name = "longitude" ;
            lon:units = "degrees_east" ;
    double lat(lat) ;
            lat:long_name = "latitude coordinate" ;
            lat:standard_name = "latitude" ;
            lat:units = "degrees_north" ;
    byte m20tree(lat, lon) ;
            m20tree:long_name = "m20tree" ;

```

.  
.  
.

There are a couple versions of these files floating around but I can’t remember which ones have changed over time. Check that first.