protected GeoElement[] processConic(Equation equ) {
double a = 0, b = 0, c = 0, d = 0, e = 0, f = 0;
GeoElement[] ret = new GeoElement[1];
GeoConic conic;
String label = equ.getLabel();
Polynomial lhs = equ.getNormalForm();
boolean isExplicit = equ.isExplicit("y");
boolean isSpecific = !isExplicit && (equ.isExplicit("yy") || equ.isExplicit("xx"));
boolean isIndependent = lhs.isConstant();
if (isIndependent) {
a = lhs.getCoeffValue("xx");
b = lhs.getCoeffValue("xy");
c = lhs.getCoeffValue("yy");
d = lhs.getCoeffValue("x");
e = lhs.getCoeffValue("y");
f = lhs.getCoeffValue("");
conic = kernel.Conic(label, a, b, c, d, e, f);
} else conic = kernel.DependentConic(label, equ);
if (isExplicit) {
conic.setToExplicit();
conic.updateRepaint();
} else if (isSpecific || conic.getType() == GeoConic.CONIC_CIRCLE) {
conic.setToSpecific();
conic.updateRepaint();
}
ret[0] = conic;
return ret;
}
protected GeoElement[] processImplicitPoly(Equation equ) {
GeoElement[] ret = new GeoElement[1];
String label = equ.getLabel();
Polynomial lhs = equ.getNormalForm();
boolean isIndependent = !equ.isFunctionDependent() && lhs.isConstant();
GeoImplicitPoly poly;
GeoElement geo = null;
if (isIndependent) {
poly = kernel.ImplicitPoly(label, lhs);
poly.setUserInput(equ);
geo = poly;
} else {
geo = kernel.DependentImplicitPoly(label, equ); // might also return Line or Conic
if (geo instanceof GeoUserInputElement) {
((GeoUserInputElement) geo).setUserInput(equ);
}
}
ret[0] = geo;
// Application.debug("User Input: "+equ);
ret[0].updateRepaint();
return ret;
}
protected GeoElement[] processLine(Equation equ, boolean inequality) {
double a = 0, b = 0, c = 0;
GeoLine line;
GeoElement[] ret = new GeoElement[1];
String label = equ.getLabel();
Polynomial lhs = equ.getNormalForm();
boolean isExplicit = equ.isExplicit("y");
boolean isIndependent = lhs.isConstant();
if (isIndependent) {
// get coefficients
a = lhs.getCoeffValue("x");
b = lhs.getCoeffValue("y");
c = lhs.getCoeffValue("");
line = kernel.Line(label, a, b, c);
} else line = kernel.DependentLine(label, equ);
if (isExplicit) {
line.setToExplicit();
line.updateRepaint();
}
ret[0] = line;
return ret;
}
public GeoElement[] processEquation(Equation equ) throws MyError {
// Application.debug("EQUATION: " + equ);
// Application.debug("NORMALFORM POLYNOMIAL: " + equ.getNormalForm());
try {
equ.initEquation();
// Application.debug("EQUATION: " + equ.getNormalForm());
// check no terms in z
checkNoTermsInZ(equ);
if (equ.isFunctionDependent()) {
return processImplicitPoly(equ);
}
// consider algebraic degree of equation
// check not equation of eg plane
switch (equ.degree()) {
// linear equation -> LINE
case 1:
return processLine(equ, false);
// quadratic equation -> CONIC
case 2:
return processConic(equ);
default:
// test for "y= <rhs>" here as well
if (equ.getLHS().toString().trim().equals("y")) {
Function fun = new Function(equ.getRHS());
// try to use label of equation
fun.setLabel(equ.getLabel());
return processFunction(null, fun);
}
return processImplicitPoly(equ);
}
} catch (MyError eqnError) {
eqnError.printStackTrace();
// invalid equation: maybe a function of form "y = <rhs>"?
String lhsStr = equ.getLHS().toString().trim();
if (lhsStr.equals("y")) {
try {
// try to create function from right hand side
Function fun = new Function(equ.getRHS());
// try to use label of equation
fun.setLabel(equ.getLabel());
return processFunction(null, fun);
} catch (MyError funError) {
funError.printStackTrace();
}
}
// throw invalid equation error if we get here
if (eqnError.getMessage() == "InvalidEquation") throw eqnError;
else {
String[] errors = {"InvalidEquation", eqnError.getLocalizedMessage()};
throw new MyError(app, errors);
}
}
}
public GeoElement[] processExpressionNode(ExpressionNode n) throws MyError {
// command is leaf: process command
if (n.isLeaf()) {
ExpressionValue leaf = n.getLeft();
if (leaf instanceof Command) {
Command c = (Command) leaf;
c.setLabels(n.getLabels());
return cmdDispatcher.processCommand(c, true);
} else if (leaf instanceof Equation) {
Equation eqn = (Equation) leaf;
eqn.setLabels(n.getLabels());
return processEquation(eqn);
} else if (leaf instanceof Function) {
Function fun = (Function) leaf;
fun.setLabels(n.getLabels());
return processFunction(n, fun);
} else if (leaf instanceof FunctionNVar) {
FunctionNVar fun = (FunctionNVar) leaf;
fun.setLabels(n.getLabels());
return processFunctionNVar(n, fun);
}
}
// ELSE: resolve variables and evaluate expressionnode
n.resolveVariables();
eval = n.evaluate();
boolean dollarLabelFound = false;
ExpressionNode myNode = n;
if (myNode.isLeaf()) myNode = myNode.getLeftTree();
// leaf (no new label specified): just return the existing GeoElement
if (eval.isGeoElement()
&& n.getLabel() == null
&& !(n.operation.equals(Operation.ELEMENT_OF))) {
// take care of spreadsheet $ names: don't loose the wrapper ExpressionNode here
// check if we have a Variable
switch (myNode.getOperation()) {
case $VAR_COL:
case $VAR_ROW:
case $VAR_ROW_COL:
// don't do anything here: we need to keep the wrapper ExpressionNode
// and must not return the GeoElement here
dollarLabelFound = true;
break;
default:
// return the GeoElement
GeoElement[] ret = {(GeoElement) eval};
return ret;
}
}
if (eval.isBooleanValue()) return processBoolean(n, eval);
else if (eval.isNumberValue()) return processNumber(n, eval);
else if (eval.isVectorValue()) return processPointVector(n, eval);
else if (eval.isVector3DValue()) return processPointVector3D(n, eval);
else if (eval.isTextValue()) return processText(n, eval);
else if (eval instanceof MyList) {
return processList(n, (MyList) eval);
} else if (eval instanceof Function) {
return processFunction(n, (Function) eval);
} else if (eval instanceof FunctionNVar) {
return processFunctionNVar(n, (FunctionNVar) eval);
}
// we have to process list in case list=matrix1(1), but not when list=list2
else if (eval instanceof GeoList && myNode.hasOperations()) {
Application.debug("should work");
return processList(n, ((GeoList) eval).getMyList());
} else if (eval.isGeoElement()) {
// e.g. B1 = A1 where A1 is a GeoElement and B1 does not exist yet
// create a copy of A1
if (n.getLabel() != null || dollarLabelFound) {
return processGeoCopy(n.getLabel(), n);
}
}
// REMOVED due to issue 131: http://code.google.com/p/geogebra/issues/detail?id=131
// // expressions like 2 a (where a:x + y = 1)
// // A1=b doesn't work for these objects
// else if (eval instanceof GeoLine) {
// if (((GeoLine)eval).getParentAlgorithm() instanceof AlgoDependentLine) {
// GeoElement[] ret = {(GeoElement) eval };
// return ret;
// }
//
// }
// if we get here, nothing worked
Application.debug("Unhandled ExpressionNode: " + eval + ", " + eval.getClass());
return null;
}
protected void checkNoTermsInZ(Equation equ) {
if (!equ.getNormalForm().isFreeOf('z')) throw new MyError(app, "InvalidEquation");
}