Examples with VCUnitException cbit.vcell.units.VCUnitException used on opensource projects

Example 6 with VCUnitException

use of cbit.vcell.units.VCUnitException in project vcell by virtualcell.

the class MathMapping_4_8 method getIdentifierSubstitutions.

/**
 * Substitutes appropriate variables for speciesContext bindings
 *
 * @return cbit.vcell.parser.Expression
 * @param origExp cbit.vcell.parser.Expression
 * @param structureMapping cbit.vcell.mapping.StructureMapping
 */
protected Expression getIdentifierSubstitutions(Expression origExp, VCUnitDefinition desiredExpUnitDef, StructureMapping structureMapping) throws ExpressionException, MappingException {
    String[] symbols = origExp.getSymbols();
    if (symbols == null) {
        return origExp;
    }
    VCUnitDefinition expUnitDef = null;
    try {
        VCUnitEvaluator unitEvaluator = new VCUnitEvaluator(simContext.getModel().getUnitSystem());
        expUnitDef = unitEvaluator.getUnitDefinition(origExp);
        if (desiredExpUnitDef == null) {
            String expStr = origExp.renameBoundSymbols(getNameScope()).infix();
            System.out.println("...........exp='" + expStr + "', desiredUnits are null");
            localIssueList.add(new Issue(origExp, issueContext, IssueCategory.Units, "expected=[null], observed=[" + expUnitDef.getSymbol() + "]", Issue.SEVERITY_WARNING));
        } else if (expUnitDef == null) {
            String expStr = origExp.renameBoundSymbols(getNameScope()).infix();
            System.out.println("...........exp='" + expStr + "', evaluated Units are null");
            localIssueList.add(new Issue(origExp, issueContext, IssueCategory.Units, "expected=[" + desiredExpUnitDef.getSymbol() + "], observed=[null]", Issue.SEVERITY_WARNING));
        } else if (desiredExpUnitDef.isTBD()) {
            String expStr = origExp.renameBoundSymbols(getNameScope()).infix();
            System.out.println("...........exp='" + expStr + "', desiredUnits are [" + desiredExpUnitDef.getSymbol() + "] and expression units are [" + expUnitDef.getSymbol() + "]");
            localIssueList.add(new Issue(origExp, issueContext, IssueCategory.Units, "expected=[" + desiredExpUnitDef.getSymbol() + "], observed=[" + expUnitDef.getSymbol() + "] for exp = " + expStr, Issue.SEVERITY_WARNING));
        } else if (!desiredExpUnitDef.isEquivalent(expUnitDef) && !expUnitDef.isTBD()) {
            String expStr = origExp.renameBoundSymbols(getNameScope()).infix();
            System.out.println("...........exp='" + expStr + "', desiredUnits are [" + desiredExpUnitDef.getSymbol() + "] and expression units are [" + expUnitDef.getSymbol() + "]");
            localIssueList.add(new Issue(origExp, issueContext, IssueCategory.Units, "expected=[" + desiredExpUnitDef.getSymbol() + "], observed=[" + expUnitDef.getSymbol() + "] for exp = " + expStr, Issue.SEVERITY_WARNING));
        }
    } catch (VCUnitException e) {
        String expStr = origExp.renameBoundSymbols(getNameScope()).infix();
        System.out.println(".........exp='" + expStr + "' exception='" + e.getMessage() + "'");
        localIssueList.add(new Issue(origExp, issueContext, IssueCategory.Units, "expected=[" + ((desiredExpUnitDef != null) ? (desiredExpUnitDef.getSymbol()) : ("null")) + "], exception=" + e.getMessage(), Issue.SEVERITY_WARNING));
    } catch (ExpressionException e) {
        String expStr = origExp.renameBoundSymbols(getNameScope()).infix();
        System.out.println(".........exp='" + expStr + "' exception='" + e.getMessage() + "'");
        localIssueList.add(new Issue(origExp, issueContext, IssueCategory.Units, "expected=[" + ((desiredExpUnitDef != null) ? (desiredExpUnitDef.getSymbol()) : ("null")) + "], exception=" + e.getMessage(), Issue.SEVERITY_WARNING));
    } catch (Exception e) {
        e.printStackTrace(System.out);
        localIssueList.add(new Issue(origExp, issueContext, IssueCategory.Units, "expected=[" + ((desiredExpUnitDef != null) ? (desiredExpUnitDef.getSymbol()) : ("null")) + "], exception=" + e.getMessage(), Issue.SEVERITY_WARNING));
    }
    Expression newExp = new Expression(origExp);
    for (int i = 0; i < symbols.length; i++) {
        SymbolTableEntry ste = origExp.getSymbolBinding(symbols[i]);
        if (ste == null) {
            throw new ExpressionBindingException("symbol '" + symbols[i] + "' not bound");
        // ste = simContext.getGeometryContext().getModel().getSpeciesContext(symbols[i]);
        }
        if (ste != null) {
            String newName = getMathSymbol(ste, structureMapping);
            if (!newName.equals(symbols[i])) {
                newExp.substituteInPlace(new Expression(symbols[i]), new Expression(newName));
            }
        }
    }
    return newExp;
}

Example 7 with VCUnitException

use of cbit.vcell.units.VCUnitException in project vcell by virtualcell.

the class AbstractMathMapping method getIdentifierSubstitutions.

/**
 * Substitutes appropriate variables for speciesContext bindings
 *
 * @return cbit.vcell.parser.Expression
 * @param origExp cbit.vcell.parser.Expression
 * @param structureMapping cbit.vcell.mapping.StructureMapping
 */
protected Expression getIdentifierSubstitutions(Expression origExp, VCUnitDefinition desiredExpUnitDef, GeometryClass geometryClass) throws ExpressionException, MappingException {
    String[] symbols = origExp.getSymbols();
    if (symbols == null) {
        return origExp;
    }
    VCUnitDefinition expUnitDef = null;
    try {
        VCUnitEvaluator unitEvaluator = new VCUnitEvaluator(simContext.getModel().getUnitSystem());
        expUnitDef = unitEvaluator.getUnitDefinition(origExp);
        if (desiredExpUnitDef == null) {
            String expStr = origExp.renameBoundSymbols(getNameScope()).infix();
            System.out.println("...........exp='" + expStr + "', desiredUnits are null");
            localIssueList.add(new Issue(origExp, issueContext, IssueCategory.Units, "expected=[null], observed=[" + expUnitDef.getSymbol() + "]", Issue.SEVERITY_WARNING));
        } else if (expUnitDef == null) {
            String expStr = origExp.renameBoundSymbols(getNameScope()).infix();
            System.out.println("...........exp='" + expStr + "', evaluated Units are null");
            localIssueList.add(new Issue(origExp, issueContext, IssueCategory.Units, "expected=[" + desiredExpUnitDef.getSymbol() + "], observed=[null]", Issue.SEVERITY_WARNING));
        } else if (desiredExpUnitDef.isTBD()) {
            String expStr = origExp.renameBoundSymbols(getNameScope()).infix();
            // System.out.println("...........exp='"+expStr+"', desiredUnits are ["+desiredExpUnitDef.getSymbol()+"] and expression units are ["+expUnitDef.getSymbol()+"]");
            localIssueList.add(new Issue(origExp, issueContext, IssueCategory.Units, "expected=[" + desiredExpUnitDef.getSymbol() + "], observed=[" + expUnitDef.getSymbol() + "] for exp = " + expStr, Issue.SEVERITY_WARNING));
        } else if (!desiredExpUnitDef.isEquivalent(expUnitDef) && !expUnitDef.isTBD()) {
            String expStr = origExp.renameBoundSymbols(getNameScope()).infix();
            // System.out.println("...........exp='"+expStr+"', desiredUnits are ["+desiredExpUnitDef.getSymbol()+"] and expression units are ["+expUnitDef.getSymbol()+"]");
            localIssueList.add(new Issue(origExp, issueContext, IssueCategory.Units, "expected=[" + desiredExpUnitDef.getSymbol() + "], observed=[" + expUnitDef.getSymbol() + "] for exp = " + expStr, Issue.SEVERITY_WARNING));
        }
    } catch (VCUnitException e) {
        String expStr = origExp.renameBoundSymbols(getNameScope()).infix();
        System.out.println(".........exp='" + expStr + "' exception='" + e.getMessage() + "'");
        localIssueList.add(new Issue(origExp, issueContext, IssueCategory.Units, "expected=[" + ((desiredExpUnitDef != null) ? (desiredExpUnitDef.getSymbol()) : ("null")) + "], exception=" + e.getMessage(), Issue.SEVERITY_WARNING));
    } catch (ExpressionException e) {
        String expStr = origExp.renameBoundSymbols(getNameScope()).infix();
        System.out.println(".........exp='" + expStr + "' exception='" + e.getMessage() + "'");
        localIssueList.add(new Issue(origExp, issueContext, IssueCategory.Units, "expected=[" + ((desiredExpUnitDef != null) ? (desiredExpUnitDef.getSymbol()) : ("null")) + "], exception=" + e.getMessage(), Issue.SEVERITY_WARNING));
    } catch (Exception e) {
        e.printStackTrace(System.out);
        localIssueList.add(new Issue(origExp, issueContext, IssueCategory.Units, "expected=[" + ((desiredExpUnitDef != null) ? (desiredExpUnitDef.getSymbol()) : ("null")) + "], exception=" + e.getMessage(), Issue.SEVERITY_WARNING));
    }
    Expression newExp = new Expression(origExp);
    // 
    // flatten user-defined functions
    // 
    FunctionInvocation[] functionInvocations = newExp.getFunctionInvocations(new FunctionFilter() {

        @Override
        public boolean accept(String functionName, FunctionType functionType) {
            return functionType == FunctionType.USERDEFINED;
        }
    });
    for (FunctionInvocation functionInvocation : functionInvocations) {
        if (functionInvocation.getSymbolTableFunctionEntry() instanceof Model.ModelFunction) {
            ModelFunction modelFunction = (ModelFunction) functionInvocation.getSymbolTableFunctionEntry();
            newExp.substituteInPlace(functionInvocation.getFunctionExpression(), modelFunction.getFlattenedExpression(functionInvocation));
        }
    }
    // 
    // then substitute Math symbols for Biological symbols.
    // 
    newExp.bindExpression(null);
    for (int i = 0; i < symbols.length; i++) {
        SymbolTableEntry ste = origExp.getSymbolBinding(symbols[i]);
        if (ste == null) {
            throw new ExpressionBindingException("symbol '" + symbols[i] + "' not bound");
        // ste = simContext.getGeometryContext().getModel().getSpeciesContext(symbols[i]);
        }
        if (ste != null) {
            String newName = getMathSymbol(ste, geometryClass);
            if (!newName.equals(symbols[i])) {
                newExp.substituteInPlace(new Expression(symbols[i]), new Expression(newName));
            }
        }
    }
    return newExp;
}

Example 8 with VCUnitException

use of cbit.vcell.units.VCUnitException in project vcell by virtualcell.

the class Kinetics method gatherIssues.

/**
 * Insert the method's description here.
 * Creation date: (5/12/2004 2:53:13 PM)
 */
public void gatherIssues(IssueContext issueContext, List<Issue> issueList) {
    issueContext = issueContext.newChildContext(ContextType.ModelProcessDynamics, this);
    // 
    for (int i = 0; fieldUnresolvedParameters != null && i < fieldUnresolvedParameters.length; i++) {
        issueList.add(new Issue(fieldUnresolvedParameters[i], issueContext, IssueCategory.UnresolvedParameter, "Unresolved parameter '" + fieldUnresolvedParameters[i].getName() + "' in reaction '" + reactionStep.getName() + "'", Issue.SEVERITY_ERROR));
    }
    // 
    for (int i = 0; fieldKineticsParameters != null && i < fieldKineticsParameters.length; i++) {
        if (fieldKineticsParameters[i].getRole() == ROLE_UserDefined) {
            try {
                if (!isReferenced(fieldKineticsParameters[i], 0)) {
                    issueList.add(new Issue(fieldKineticsParameters[i], issueContext, IssueCategory.KineticsUnreferencedParameter, "Unreferenced Kinetic Parameter '" + fieldKineticsParameters[i].getName() + "' in reaction '" + reactionStep.getName() + "'", Issue.SEVERITY_WARNING));
                }
            } catch (ExpressionException e) {
                issueList.add(new Issue(fieldKineticsParameters[i], issueContext, IssueCategory.KineticsExpressionError, "error resolving expression " + e.getMessage(), Issue.SEVERITY_WARNING));
            } catch (ModelException e) {
                issueList.add(new Issue(getReactionStep(), issueContext, IssueCategory.CyclicDependency, "cyclic dependency in the parameter definitions", Issue.SEVERITY_ERROR));
            }
        }
    }
    // 
    if (fieldKineticsParameters != null) {
        for (KineticsParameter kineticsParameter : fieldKineticsParameters) {
            if (kineticsParameter.getExpression() == null) {
                issueList.add(new Issue(kineticsParameter, issueContext, IssueCategory.KineticsExpressionMissing, "expression is missing", Issue.SEVERITY_INFO));
            } else {
                Expression exp = kineticsParameter.getExpression();
                String[] symbols = exp.getSymbols();
                String issueMessagePrefix = "Kinetic parameter '" + kineticsParameter.getName() + "' in reaction '" + getReactionStep().getName() + "' ";
                if (symbols != null) {
                    for (int j = 0; j < symbols.length; j++) {
                        SymbolTableEntry ste = exp.getSymbolBinding(symbols[j]);
                        if (ste instanceof KineticsProxyParameter) {
                            ste = ((KineticsProxyParameter) ste).getTarget();
                        }
                        if (ste == null) {
                            issueList.add(new Issue(kineticsParameter, issueContext, IssueCategory.KineticsExpressionUndefinedSymbol, issueMessagePrefix + "references undefined symbol '" + symbols[j] + "'", Issue.SEVERITY_ERROR));
                        } else if (ste instanceof SpeciesContext) {
                            if (!getReactionStep().getModel().contains((SpeciesContext) ste)) {
                                issueList.add(new Issue(kineticsParameter, issueContext, IssueCategory.KineticsExpressionUndefinedSymbol, issueMessagePrefix + "references undefined species '" + symbols[j] + "'", Issue.SEVERITY_ERROR));
                            }
                            if (reactionStep.countNumReactionParticipants((SpeciesContext) ste) == 0) {
                                issueList.add(new Issue(kineticsParameter, issueContext, IssueCategory.KineticsExpressionNonParticipantSymbol, issueMessagePrefix + "references species context '" + symbols[j] + "', but it is not a reactant/product/catalyst of this reaction", Issue.SEVERITY_WARNING));
                            }
                        } else if (ste instanceof ModelParameter) {
                            if (!getReactionStep().getModel().contains((ModelParameter) ste)) {
                                issueList.add(new Issue(kineticsParameter, issueContext, IssueCategory.KineticsExpressionUndefinedSymbol, issueMessagePrefix + "references undefined global parameter '" + symbols[j] + "'", Issue.SEVERITY_ERROR));
                            }
                        }
                    }
                }
            }
        }
        // looking for local param which masks a global and issueing a warning
        for (KineticsParameter kineticsParameter : fieldKineticsParameters) {
            String name = kineticsParameter.getName();
            SymbolTableEntry ste = getReactionStep().getNameScope().getExternalEntry(name, getReactionStep());
            String steName;
            if (ste != null) {
                if (ste instanceof Displayable) {
                    steName = ((Displayable) ste).getDisplayType() + " " + ste.getName();
                } else {
                    steName = ste.getClass().getSimpleName() + " " + ste.getName();
                }
                String msg = steName + " is overriden by a local parameter " + name + " in reaction " + getReactionStep().getName();
                issueList.add(new Issue(kineticsParameter, issueContext, IssueCategory.Identifiers, msg, Issue.SEVERITY_WARNING));
            }
        }
    }
    try {
        // 
        // determine unit consistency for each expression
        // 
        ModelUnitSystem modelUnitSystem = getReactionStep().getModel().getUnitSystem();
        VCUnitEvaluator unitEvaluator = new VCUnitEvaluator(modelUnitSystem);
        for (int i = 0; i < fieldKineticsParameters.length; i++) {
            try {
                VCUnitDefinition paramUnitDef = fieldKineticsParameters[i].getUnitDefinition();
                VCUnitDefinition expUnitDef = unitEvaluator.getUnitDefinition(fieldKineticsParameters[i].getExpression());
                if (paramUnitDef == null) {
                    issueList.add(new Issue(fieldKineticsParameters[i], issueContext, IssueCategory.Units, "defined unit is null", Issue.SEVERITY_WARNING));
                } else if (paramUnitDef.isTBD()) {
                    issueList.add(new Issue(fieldKineticsParameters[i], issueContext, IssueCategory.Units, "undefined unit " + modelUnitSystem.getInstance_TBD().getSymbol(), Issue.SEVERITY_WARNING));
                } else if (expUnitDef == null) {
                    issueList.add(new Issue(fieldKineticsParameters[i], issueContext, IssueCategory.Units, "computed unit is null", Issue.SEVERITY_WARNING));
                } else if (paramUnitDef.isTBD() || (!paramUnitDef.isEquivalent(expUnitDef) && !expUnitDef.isTBD())) {
                    issueList.add(new Issue(fieldKineticsParameters[i], issueContext, IssueCategory.Units, "inconsistent units, defined=[" + fieldKineticsParameters[i].getUnitDefinition().getSymbol() + "], computed=[" + expUnitDef.getSymbol() + "]", Issue.SEVERITY_WARNING));
                }
            } catch (VCUnitException e) {
                issueList.add(new Issue(fieldKineticsParameters[i], issueContext, IssueCategory.Units, e.getMessage(), Issue.SEVERITY_WARNING));
            } catch (ExpressionException e) {
                issueList.add(new Issue(fieldKineticsParameters[i], issueContext, IssueCategory.Units, e.getMessage(), Issue.SEVERITY_WARNING));
            }
        }
    } catch (Throwable e) {
        issueList.add(new Issue(getReactionStep(), issueContext, IssueCategory.Units, "unexpected exception: " + e.getMessage(), Issue.SEVERITY_INFO));
    }
    // 
    for (int i = 0; i < fieldKineticsParameters.length; i++) {
        RealInterval simpleBounds = bounds[fieldKineticsParameters[i].getRole()];
        if (simpleBounds != null) {
            String parmName = reactionStep.getNameScope().getName() + "." + fieldKineticsParameters[i].getName();
            issueList.add(new SimpleBoundsIssue(fieldKineticsParameters[i], issueContext, simpleBounds, "parameter " + parmName + ": must be within " + simpleBounds.toString()));
        }
    }
}

Example 9 with VCUnitException

use of cbit.vcell.units.VCUnitException in project vcell by virtualcell.

the class VCUnitEvaluator method getUnitDefinition.

private VCUnitDefinition getUnitDefinition(SimpleNode node, UnitsHashMap unitsHashMap) throws ExpressionException, VCUnitException {
    // temp variable
    VCUnitDefinition unit = null;
    if (node == null) {
        return null;
    }
    if (node instanceof ASTAndNode || node instanceof ASTOrNode || node instanceof ASTNotNode) {
        for (int i = 0; i < node.jjtGetNumChildren(); i++) {
            SimpleNode child = (SimpleNode) node.jjtGetChild(i);
            VCUnitDefinition childUnit = getUnitDefinition(child, unitsHashMap);
            if (!childUnit.isEquivalent(unitSystem.getInstance_DIMENSIONLESS())) {
                throw new VCUnitException("argument to boolean expression '" + child.infixString(SimpleNode.LANGUAGE_DEFAULT) + "' must be dimensionless");
            }
        }
        return unitSystem.getInstance_DIMENSIONLESS();
    } else if (node instanceof ASTRelationalNode) {
        ArrayList<VCUnitDefinition> units = new ArrayList<VCUnitDefinition>();
        for (int i = 0; i < node.jjtGetNumChildren(); i++) {
            units.add(getUnitDefinition((SimpleNode) node.jjtGetChild(i), unitsHashMap));
        }
        // looking for imcompatabilities
        computeUnit(node, (VCUnitDefinition[]) units.toArray(new VCUnitDefinition[units.size()]), true);
        return unitSystem.getInstance_DIMENSIONLESS();
    } else if (node instanceof ASTAddNode || node instanceof ASTMinusTermNode) {
        ArrayList<VCUnitDefinition> units = new ArrayList<VCUnitDefinition>();
        for (int i = 0; i < node.jjtGetNumChildren(); i++) {
            units.add(getUnitDefinition((SimpleNode) node.jjtGetChild(i), unitsHashMap));
        }
        return computeUnit(node, (VCUnitDefinition[]) units.toArray(new VCUnitDefinition[units.size()]), true);
    } else if (node instanceof ASTMultNode) {
        if (node.jjtGetNumChildren() == 1) {
            return getUnitDefinition((SimpleNode) node.jjtGetChild(0), unitsHashMap);
        }
        VCUnitDefinition accumUnit = null;
        for (int i = 0; i < node.jjtGetNumChildren(); i++) {
            SimpleNode child = (SimpleNode) node.jjtGetChild(i);
            unit = getUnitDefinition(child, unitsHashMap);
            if (unit.isTBD()) {
                return unit;
            }
            if (accumUnit == null) {
                accumUnit = unit;
            } else {
                accumUnit = accumUnit.multiplyBy(unit);
            }
        }
        return accumUnit;
    } else if (node instanceof ASTInvertTermNode) {
        SimpleNode child = (SimpleNode) node.jjtGetChild(0);
        unit = getUnitDefinition(child, unitsHashMap);
        if (unit.isTBD()) {
            return unit;
        } else {
            return unit.getInverse();
        }
    } else if (node instanceof DerivativeNode) {
        unit = getUnitDefinition((SimpleNode) node.jjtGetChild(1), unitsHashMap);
        return getUnitDefinition((SimpleNode) node.jjtGetChild(0), unitsHashMap).divideBy(unit);
    } else if (node instanceof ASTLaplacianNode) {
        return unitSystem.getInstance_TBD();
    // unit = unitSystem.Instance(ModelUnitSystem.UNITSYMBOL_um);
    // return getUnitDefinition((SimpleNode)node.jjtGetChild(0),unitsHashMap).divideBy(unit).divideBy(unit);
    } else if (node instanceof ASTFloatNode) {
        // return TBD instead of dimensionless.
        return unitSystem.getInstance_TBD();
    } else if (node instanceof ASTFuncNode) {
        String functionName = ((ASTFuncNode) node).getName();
        if (functionName.equalsIgnoreCase("pow")) {
            SimpleNode child0 = (SimpleNode) node.jjtGetChild(0);
            SimpleNode child1 = (SimpleNode) node.jjtGetChild(1);
            VCUnitDefinition unit0 = getUnitDefinition(child0, unitsHashMap);
            VCUnitDefinition unit1 = getUnitDefinition(child1, unitsHashMap);
            if (!unit1.isEquivalent(unitSystem.getInstance_DIMENSIONLESS()) && !unit1.isTBD()) {
                throw new VCUnitException("exponent of '" + node.infixString(SimpleNode.LANGUAGE_DEFAULT) + "' has units of " + unit0);
            }
            if (unit0.isEquivalent(unitSystem.getInstance_DIMENSIONLESS()) || unit0.isTBD()) {
                return unit0;
            }
            try {
                double d = ((SimpleNode) node.jjtGetChild(1)).evaluateConstant();
                RationalNumber rn = RationalNumber.getApproximateFraction(d);
                return unit0.raiseTo(rn);
            } catch (ExpressionException e) {
                // ????? don't know the unit now
                return unitSystem.getInstance_TBD();
            }
        } else if (functionName.equalsIgnoreCase("exp")) {
            SimpleNode child0 = (SimpleNode) node.jjtGetChild(0);
            VCUnitDefinition unit0 = getUnitDefinition(child0, unitsHashMap);
            if (!unit0.isEquivalent(unitSystem.getInstance_DIMENSIONLESS()) && !unit0.isTBD()) {
                throw new VCUnitException("exponent of exp() '" + node.infixString(SimpleNode.LANGUAGE_DEFAULT) + "' has units of " + unit0);
            }
            return unitSystem.getInstance_DIMENSIONLESS();
        } else if (functionName.equalsIgnoreCase("sqrt")) {
            SimpleNode child0 = (SimpleNode) node.jjtGetChild(0);
            VCUnitDefinition unit0 = getUnitDefinition(child0, unitsHashMap);
            if (unit0.isEquivalent(unitSystem.getInstance_DIMENSIONLESS()) || unit0.isTBD()) {
                return unit0;
            }
            RationalNumber rn = new RationalNumber(1, 2);
            return unit0.raiseTo(rn);
        } else if (functionName.equalsIgnoreCase("abs") || functionName.equalsIgnoreCase("min") || functionName.equalsIgnoreCase("max")) {
            return getUnitDefinition((SimpleNode) node.jjtGetChild(0), unitsHashMap);
        } else if (((ASTFuncNode) node).getFunction() == FunctionType.USERDEFINED) {
            ASTFuncNode funcNode = (ASTFuncNode) node;
            SymbolTableFunctionEntry stfe = funcNode.getSymbolTableFunctionEntry();
            if (stfe != null) {
                if (stfe.getUnitDefinition() != null) {
                    return stfe.getUnitDefinition();
                }
            }
            return unitSystem.getInstance_TBD();
        } else {
            return unitSystem.getInstance_DIMENSIONLESS();
        }
    } else if (node instanceof ASTPowerNode) {
        SimpleNode child0 = (SimpleNode) node.jjtGetChild(0);
        SimpleNode child1 = (SimpleNode) node.jjtGetChild(1);
        VCUnitDefinition unit0 = getUnitDefinition(child0, unitsHashMap);
        VCUnitDefinition unit1 = getUnitDefinition(child1, unitsHashMap);
        if (!unit1.isEquivalent(unitSystem.getInstance_DIMENSIONLESS()) && !unit1.isTBD()) {
            throw new VCUnitException("exponent of '" + node.infixString(SimpleNode.LANGUAGE_DEFAULT) + "' has units of " + unit0);
        }
        if (unit0.isEquivalent(unitSystem.getInstance_DIMENSIONLESS())) {
            return unitSystem.getInstance_DIMENSIONLESS();
        }
        boolean bConstantExponent = false;
        double exponentValue = 1;
        try {
            exponentValue = child1.evaluateConstant();
            bConstantExponent = true;
        } catch (ExpressionException e) {
            bConstantExponent = false;
        }
        if (bConstantExponent) {
            // 
            if (unit0.isTBD()) {
                return unitSystem.getInstance_TBD();
            } else {
                RationalNumber rn = RationalNumber.getApproximateFraction(exponentValue);
                return unit0.raiseTo(rn);
            }
        } else {
            return unitSystem.getInstance_TBD();
        }
    } else if (node instanceof ASTIdNode) {
        SymbolTableEntry ste = ((ASTIdNode) node).symbolTableEntry;
        unit = unitsHashMap.get(ste);
        if (unit == null) {
            unit = ste.getUnitDefinition();
            if (unit == null) {
                throw new ExpressionException("No unit found for expression node: " + node.toString());
            } else {
                unitsHashMap.put(ste, unit);
            }
        }
        return unit;
    } else {
        throw new ExpressionException("node type " + node.getClass().toString() + " not supported yet");
    }
}