Software for modeling circuit theory-based connectivity at any scale. We developed GFlow to solve large ecological problems in a High Performance Computing environment. If solving a small problem or if you are willing to sacrifice some performance, it can be deployed on a desktop computer running modern versions of Linux or Mac OS X.

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Installation

Please download latest release with sample data.

Mac OS X Install Instructions

The easiest way to setup your environment is with the Homebrew package manager. After Homebrew is set up, run the following commands to install the required packages:

brew update
brew install openmpi
brew install homebrew/science/hypre
brew install homebrew/science/petsc
brew install coreutils					# optional

Note: Advanced users may build their own versions of PETSc and an MPI library, gflow does not require any specific preconditioner (we recommend hypre) nor does it depend on a particular MPI implementation.

With the required packages installed, gflow can be built inside its containing folder by running the following terminal command there:

 make

If you encounter errors related to PETSc, you may have to edit the Makefile to change the value of the PETSC_DIR variable. For example, during the above proceedure, homebrew installed petsc here:

/usr/local/Cellar/petsc/3.7.3/real

Currently, there is no mechanism to automatically copy the gflow.x binary to a centrally-located directory.

Linux Install Instructions

While users are free to build GFlow dependcies themselves, we find a package manager is suitable for many users and the easiest way to get started. For example on Ubuntu based systems you can use the default package management tool called apt or optionally install and use Aptitude

To Install Aptitude, run the following command in terminal:

sudo apt-get install aptitude

Then the dependices using aptitude (you may need to be root e.g., use sudo prefix as above):

aptitude install openmpi-bin
aptitude install libhypre-dev
aptitude install petsc-dev

Note: Advanced users may build their own versions of PETSc and an MPI library, gflow does not require any specific preconditioner (we recommend hypre) nor does it depend on a particular MPI implementation but it needs PETSc >= 3.7.3 that is available as ready to install/use package on Ubuntu v. 16.10 (but not on 16.04).

With the required packages installed, gflow can be built from its containing folder by running the following terminal command there:

 make

If you encounter errors related to PETSc, you may have to edit the Makefile to change the value of the PETSC_DIR variable. For example, during the above proceedure, aptitude installed petsc here:

/usr/lib/petscdir/3.7.3/x86_64-linux-gnu-real

Note: If you receive warnings after make but no errors, please try to proceed with using GFlow

Currently, there is no mechanism to automatically copy the gflow.x binary to a centrally-located directory.

Windows

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Running

Instructions below apply to Desktop Computers. Advanced use for cluster computing follows a very similar proceedure after dependencies are installed. Details of cluster scheduling/submission scripts are typically unique to given cyberinfrastructure.

Easiest using Terminal

1. Navigate to the directory where you downloaded GFlow and extract.

2. Extract the zipped example input files (inputs.tar.gz) into the current GFlow directory. E.g., using terminal:

   tar xvf inputs.tar.gz
   

3. Open the commented example execute_example.sh script with your favorite text editor and examine the format, default settings, and save any necessary adjustments. Otherwise, the script is ready to submit and solve the example problem.

4. If terminal is not open, open now and navigate to GFlow directory. Execute script:

   sh execute_example.sh
   

Note: You may also need to edit the execute_example.sh file to change the PETSC_DIR parameter as done previously for the Makefile file

5. To stop execution after any iteration, simply open another Terminal window and navigate to the working directory of GFlow. Enter touch killswitch. The simulation will cleanly exit after the current calculation and write the existing current density summation.

   1. To print the existing summation of current density without stopping the execution, simply open another Terminal window and navigate to the working directory of GFlow. We need to get the Process ID (PID). Enter:

      ps aux | grep mpiexec
      

   2. Take note of the returned PID value and enter this where your value = PID:

      kill -USR1 PID