
Show HN: Trajectory – an open-source educational tool to model financial future - jmort
http://blabr.io/?2efbdcc151a2e3e57d75
======
jmort
Hey all, I wrote this little Blab after struggling to visualize the impact of
budgeting and investments in the long term. People kept telling me to save and
invest, but I wanted to see empirically why this is true.

Features I'd like to add:

    
    
      - Better taxation rules
      - Specific asset classes and investment accounts with 
        associated taxation, withdraw limits, and contribution limits
      - Investment allocation strategy with a changing risk profile 
        and tax conscious account allocation
      - Social security income
      - Highlighting the "important" factors 
        (i.e., the ones that impact the plot the most)
      - A probabilistic simulation to get a better result estimate 
        (i.e., confidence intervals)
    

If you want to contribute, that'd be awesome! You can also easily fork it. If
you have questions, I'm happy to answer them here!

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gballan
Blabr dev here. We're working on an improved plotting widget, plot2 [0], that
you're welcome to try (note how it's imported in the defs section). For
example, see [1] for plot2 applied to "Trajectory". It is fairly sound, but
there are some issues with escaping. So, e.g., we need yLabels: ["\\\$
$\\\times 1000$"], which is a bit ugly--but it works.

[0]
[http://blabr.io/?7b662930a33b1053072a](http://blabr.io/?7b662930a33b1053072a)

[1]
[http://blabr.io/?7d4d0cc9f423800f23e9](http://blabr.io/?7d4d0cc9f423800f23e9)

------
mvclark
Another Blabr dev here. This is a really nice blab. We'd targeted Blabr for
scientific computing (and, in particular, for STEM and conceptual modelling),
but you've demonstrated that it also works well for other kinds of online,
interactive computation.

Based on your work, it occurs to us that we need to improve some things for
non-scientific applications, e.g., number formatting (dollars/cents, thousands
separators). Please let us know if there are any other features that would
help you do this kind of financial modelling work. Or any feedback in general.
Thanks!

~~~
jmort
Thanks! Really an excellent tool! I'd originally written a shiny app, but this
was much better!

Other than the plot (thanks, gballan), it would be nice to adjust the width of
layout cells, especially for the code cells. It would also be cool to adjust
the spacing between cells to reduce whitespace when another cell in the same
row takes up a huge amount but others do not.

I was not clear how to place markdown text in between or after tables and
sliders but might have just missed how to do that.

Thanks again!

