Show financial models in GUI when doing calculations
@robert.ancell
Submitted by Robert Ancell Link to original bug (#600764)
Description
The financial dialogs are an improvement on the register based financial calculations but we can do better...
We should have a graphical financial calculator (either replaces the buttons or in a seperate dialog) that shows the financial model being calculated in graph form (money versus time). Then have input fields for each constraint and update in real time.
Shouldn't be too hard to do with cairo etc.
I don't know what hardly any of the financial calculations are trying to do (or know the jargon), if you know or use financial operations list the models, use cases and jargon here so we can work out what to implement.
e.g. one model I can see is "Investment with periodic interest" with a graph that looks like this:
$
^
|
final-| +----
value | +----+ /
| +----+.........................
initial-|----+.............................. interest rate
value | /
|
+-------------------> periods
0 1 2 3
There are at least three useful calculations:
- With a given initial value and interest rate how much money do I have after n periods?
- With a given initial value and interest rate how much periods does it take to have at least $n?
- With a given initial value, final value and number of periods what interest rate do I need to achieve this?
Version: git master