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modelica / ModelicaStandardLibrary

Free (standard conforming) library to model mechanical (1D/3D), electrical (analog, digital, machines), magnetic, thermal, fluid, control systems and hierarchical state machines. Also numerical functions and functions for strings, files and streams are included.
https://doc.modelica.org
BSD 3-Clause "New" or "Revised" License
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Not quite 90 degrees, in Modelica.Mechanics.Rotational.Examples.CoupledClutches #1975

Closed modelica-trac-importer closed 7 years ago

modelica-trac-importer commented 7 years ago

Reported by hansolsson on 4 Apr 2016 12:54 UTC Some example models use 1.57 as an approximation for pi/2 - that seems a bit inaccurate, and is especially an issue if you look at it in degrees:

Modelica.Mechanics.Rotational.Examples.CoupledClutches Modelica.Blocks.Examples.PID_Controller

I would prefer to use more digits - even if it requires updated reference results for these two models.

Whereas the following ones use a good value (also for 45 degrees). Modelica.Mechanics.Rotational.Examples.Backlash Modelica.Fluid.Fittings.BaseClasses.Bends.CurvedBend.Geometry Modelica.Mechanics.MultiBody.Examples.Elementary.RollingWheelSetDriving

(The ones for pi also use good values, and 2*pi is only used in Modelica.Electrical.Analog.Examples.ShowSaturatingInductor for stopTime and it seems good enough.)

Clearly this is not a blocking issue.

Migrated-From: https://trac.modelica.org/Modelica/ticket/1975

beutlich commented 7 years ago

@HansOlsson Resolved in the most straight-forward way in branches master and maint/3.2.2.