Vensim 6.4 Released.

Get It

Vensim 6.4 is available for download or purchase in the Vensim Store.

Upgrades are easy – just visit the download page and enter your license key information.

  • If your maintenance is current, you can download immediately.
  • If you don’t have a current license, you can extend your maintenance easily – just follow the Upgrade link that will be generated.
  • Can’t find your license? Need other options? No problem – contact sales at vensim@vensim.com for help, volume quotes and other information.

PLE is always free for noncommercial use, and the Model Reader is free for redistribution of any model.

What’s New?

Optimization improvements

  • All optimization settings, including MCMCstochastic optimization and extended payoff types are now available directly from the user interface. See the sections on Payoff Definitions and Optimization for more details.
  • Payoff reports have been improved.
  • A new payoff type permits elements that contribute to Kalman filter updates but not to the optimization payoff.
  • Payoffs now skip points with NA values of model variables.
  • Minor bug fix to prevent randomization of MCMC internal processes.
  • Faster payoff computation.
  • Kalman filter stability has been improved, particularly for models with many measurements and few states.

Sensitivity simulation improvements

  • The VECTOR distribution has new options for testing only endpoints.
  • Improved distribution parameter validation.
  • Enhanced data export – see next item.
  • Data import/export – new functionality makes it easier to work with enterprise data sources, statistics, visualization and business intelligence packages.
  • Vensim can now import and export two new data types, relational and tidy. See: VDF2DLISTVDF2TIDYDLIST2VDFTIDY2VDF.
  • Sensitivity simulation export has been greatly enhanced, and also includes tidy and relational formats – see SENS2FILE.
  • The Runs Compare tool can now be used with non-simulation sources (i.e. .vdf files from data).
  • Many bug fixes on the Mac.