Opened 6 years ago

Closed 6 years ago

#4993 closed defect (fixed)

Parameter-dependent conditional equations are not handled by the NF

Reported by: casella Owned by: perost
Priority: high Milestone: 2.0.0
Component: New Instantiation Version:
Keywords: Cc: danieljose.penagos@…

Description

Consider the following test case

model Test 
  Real x[2];
  parameter Boolean p[2] = {false, true};
equation
  x[1] = 1;
  for i in 1:2 loop
    if p[i] then
      x[i] = 2;
    end if;
  end for;
end Test;

Section 8.3.4 of the specification states

If-equations in equation sections which do not have exclusively parameter expressions as switching conditions shall have the same number of equations in each branch

so this model is valid, since p[i] is a parameter expression.

The old front end flattens this model to

class Test2
  Real x[1];
  Real x[2];
  parameter Boolean p[1] = false;
  parameter Boolean p[2] = true;
equation
  x[1] = 1.0;
  x[2] = 2.0;
end Test2;

which is correct, and then simulates it correctly.

The NF instead produces this flat code

class Test
  Real x[1];
  Real x[2];
  parameter Boolean p[1] = false;
  parameter Boolean p[2] = true;
equation
  x[1] = 1.0;
  if p[1] then
    x[1] = 2.0;
  end if;
  if p[2] then
    x[2] = 2.0;
  end if;
end Test;

then, when trying to simulate it, produces the following error:

[1] 16:19:58 Symbolic Error
Too few equations, under-determined system. The model has 1 equation(s) and 2 variable(s).

The problem persists even when setting -d=evaluateAllParameters.

@perost, can you please make sure that these parameter dependent conditions are evaluated properly?

As an interim measure, getting them right with -d=evaluateAllParameters would already be good.

Change History (1)

comment:1 Changed 6 years ago by perost

  • Resolution set to fixed
  • Status changed from new to closed

Fixed in fd56610.

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