@Override public void compute() { // cover undefined cases if (!degree.isDefined() || !min.isDefined() || !max.isDefined() || degree.getDouble() < 0) { polynomial.setUndefined(); return; } int lower = (int) Math.ceil(min.getDouble()); int upper = (int) Math.floor(max.getDouble()); if (lower > upper || (lower == 0 && upper == 0)) { polynomial.setUndefined(); return; } // input is sane, we can do the computation int deg = (int) Math.floor(degree.getDouble()); ExpressionNode varExpr = new ExpressionNode(kernel, fv); ExpressionNode newExpr = randomCoef(deg != 0); for (int i = 1; i <= deg; i++) { newExpr = varExpr.power(new MyDouble(kernel, i)).multiply(randomCoef(i != deg)).plus(newExpr); } f.setExpression(newExpr, fv); polynomial.setFunction(f); }
@Override public void compute() { int degInt; GeoList coefs = null; fv.setVarString(f.getVarString(StringTemplate.defaultTemplate)); // px^2+qx+r; p+q+r=s; double r = f.evaluate(0); double s = f.evaluate(1); double p = 0.5 * (s + f.evaluate(-1)) - r; double q = s - p - r; boolean isQuadratic = !f.isGeoFunctionConditional(); double[] checkpoints = {1000, -1000, Math.PI, Math.E}; for (int i = 0; i < checkpoints.length; i++) { double x = checkpoints[i]; if (!Kernel.isZero(p * x * x + q * x + r - f.evaluate(x))) { // App.debug(p + "," + q + "," + r + "," // + (p * x * x + q * x + r - f.evaluate(x))); isQuadratic = false; } } if (!isQuadratic) { if (algoCoef == null) { algoCoef = new AlgoCoefficients(cons, f); algoCoef.setProtectedInput(true); algoCoef.remove(); } else { algoCoef.compute(); } coefs = algoCoef.getResult(); degInt = coefs.size() - 1; isQuadratic = coefs.isDefined() && coefs.get(0).isDefined(); for (int i = 1; i < degInt; i++) { if (2 * i != degInt && !Kernel.isZero(((GeoNumeric) coefs.get(i)).getDouble())) { isQuadratic = false; } p = ((GeoNumeric) coefs.get(0)).getDouble(); q = ((GeoNumeric) coefs.get(degInt / 2)).getDouble(); r = ((GeoNumeric) coefs.get(degInt)).getDouble(); } } else { degInt = 2; } if (degInt % 2 == 1 || degInt < 2 || !isQuadratic || Kernel.isZero(p)) { square.setUndefined(); return; } if (lastDeg != degInt) { ExpressionNode squareE; ExpressionValue fvPower; if (degInt == 2) fvPower = fv; else fvPower = new ExpressionNode(kernel, fv, Operation.POWER, new MyDouble(kernel, degInt / 2)); squareE = new ExpressionNode( kernel, new ExpressionNode( kernel, a, Operation.MULTIPLY, new ExpressionNode(kernel, fvPower, Operation.MINUS, h) .power(new MyDouble(kernel, 2))), Operation.PLUS, k); square.getFunction().setExpression(squareE); } lastDeg = degInt; fv.setVarString(f.getVarString(StringTemplate.defaultTemplate)); // if one is undefined, others are as well square.setDefined(!Double.isNaN(r)); a.set(p); h.set(-q / (2 * p)); k.set(r - q * q / (p * 4)); }