/** * Evaluate a function at a specific point in x * * @param vars Values for evaluation separated by commas, x=1,y=2,z=3 * @return function value at x */ public double eval(String vars) { // get all variables String[] tmp = vars.split(","); // double[] vd = new double[tmp.length]; for (int i = 0; i < tmp.length; i++) { String[] vv = tmp[i].split("="); if (vv.length != 2) { ErrorMessage("Error in parsing list of input variablse. Did you use val=number? "); } try { double d = Double.valueOf(vv[1].trim()).doubleValue(); jep.addVariable(vv[0].trim(), d); } catch (NumberFormatException nfe) { System.out.println("NumberFormatException: " + nfe.getMessage()); } } try { Object result = jep.evaluate(node); if (result instanceof Double) { return ((Double) jep.evaluate(node)).doubleValue(); } } catch (ParseException e) { return 0; } return 0; }
/** * Evaluate a function at a specific point for one single variable. Evaluation is done between * xmin and xmax. It is assumed that there are no any other variable involved * * @param indvars Define independent variable, like 'x' Only one variable is allowed * @param xmin xmin value for independent varible * @param xmax xmax value for independent varible * @return true if no errors */ public boolean eval(String indvars, double xmin, double xmax) { boolean suc = true; String name = proxy.getName(); int points = proxy.getPoints(); double min = xmin; double max = xmax; x = new double[points]; y = new double[points]; for (int i = 0; i < points; i++) { x[i] = min + i * (max - min) / (points - 1); jep.addVariable(indvars.trim(), x[i]); try { Object result = jep.evaluate(node); if (result instanceof Double) { y[i] = ((Double) jep.evaluate(node)).doubleValue(); } } catch (ParseException e) { jhplot.utils.Util.ErrorMessage( "Failed to parse function " + name + " Error:" + e.toString()); suc = false; } } if (suc) isEvaluated = true; return suc; } // end 1-D evaluation
/** * Create a function in any dimension evaluation. * * <p>The function may have many independent variables. * * <p> * * <h3>List of commands</h3> * * <ul> * <li>( ) parenthesis , comma * <li>+, -, unary -, unary + * <li>*, / * <li>^ (raise to a power) * <li>pi, e, All the constants in class SpecialFunction * <li>log * <li>sin, cos, tan, sinh, cosh, tanh * <li>asin, acos, atan, asinh, acosh, atanh * <li>sqrt * <li>rand * <li>exp * <li>remainder * <li>atan2 * <li>Special functions and constants. Look at the book * <li>All the functions in class SpecialFunction * <li>Independent variables x * <li>Scientific notation using "e", "E", "d", "D". * </ul> * * @prama title Title of the function * @param name String representing the function * @param vars String representing variables. Each variable should be separated by a comma. * Example "x,y,z" */ public FND(String title, String name, String vars) { this.title = title; proxy = new FProxy(3, title, name, null, new double[] {0, 0, 0, 0, 0, 0}, maxpoints, true); name = proxy.getName(); proxy.setVariables(vars); setTitle(title); lpp.setType(LinePars.F1D); jep = new XJep(); jep.addStandardConstants(); jep.addStandardFunctions(); jep.setAllowUndeclared(true); jep.setImplicitMul(true); jep.setAllowAssignment(true); // get all variables avars = vars.split(","); for (int i = 0; i < avars.length; i++) { jep.addVariable(avars[i].trim(), 0); } jep.addVariable("x", 0); try { node = jep.parse(name); processed = jep.preprocess(node); } catch (ParseException e) { } catch (Exception e) { ErrorMessage("Error in parsing " + name); } }
/** * Initialize function from proxy. * * @param f */ public FND(FProxy f) { proxy = f; String name = proxy.getName(); if (proxy.getType() != 4) { ErrorMessage("Error in parsing FND. Wrong type! " + name); return; } setTitle(proxy.getTitle()); lpp.setType(LinePars.F1D); jep = new XJep(); jep.addStandardConstants(); jep.addStandardFunctions(); jep.setAllowUndeclared(true); jep.setImplicitMul(true); jep.setAllowAssignment(true); // get all variables String vars = proxy.getVariables(); avars = vars.split(","); for (int i = 0; i < avars.length; i++) { jep.addVariable(avars[i].trim(), 0); } jep.addVariable("x", 0); try { node = jep.parse(name); processed = jep.preprocess(node); } catch (ParseException e) { } catch (Exception e) { ErrorMessage("Error in parsing " + name); } }
/** * Evaluate a function at a specific point for one single variable. Evaluation is done between * xmin and xmax * * @param indvars Define independent variable, like 'x' Only one variable is allowed * @param xmin xmin value for independent varible * @param xmax xmax value for independent varible * @param vars define values for other variables, like 'y=1,z=3' * @return true if no errors */ public boolean eval(String indvars, double xmin, double xmax, String vars) { String name = proxy.getName(); int points = proxy.getPoints(); boolean suc = true; String[] tmp = vars.split(","); // double[] vd = new double[tmp.length]; fixedVars = vars; for (int i = 0; i < tmp.length; i++) { String[] vv = tmp[i].split("="); if (vv.length != 2) { ErrorMessage("Error in parsing list of input variablse. Did you use val=number? "); } try { double d = Double.valueOf(vv[1].trim()).doubleValue(); jep.addVariable(vv[0].trim(), d); } catch (NumberFormatException nfe) { System.out.println("NumberFormatException: " + nfe.getMessage()); suc = false; } } double min = xmin; double max = xmax; x = new double[points]; y = new double[points]; for (int i = 0; i < points; i++) { x[i] = min + i * (max - min) / (points - 1); jep.addVariable(indvars.trim(), x[i]); try { Object result = jep.evaluate(node); if (result instanceof Double) { y[i] = ((Double) jep.evaluate(node)).doubleValue(); } } catch (ParseException e) { jhplot.utils.Util.ErrorMessage( "Failed to parse function " + name + " Error:" + e.toString()); suc = false; } } if (suc) isEvaluated = true; return suc; } // end 1-D evaluation
/** Treat the function as complex. */ public void simplify() { String name = proxy.getName(); try { simp = jep.simplify(processed); } catch (ParseException e) { } catch (Exception e) { ErrorMessage("Error in simplification of " + name); } }
/** Creates a ASTConstant whose value of applying the operator to its arguments. */ public ASTConstant buildConstantNode(PostfixMathCommandI pfmc, Node children[]) throws IllegalArgumentException, ParseException { /* Stack stack = new Stack(); for(int i=0;i<children.length;++i) { if(!(children[i] instanceof ASTConstant)) throw new ParseException("buildConstantNode: arguments must all be constant nodes"); stack.push(((ASTConstant) children[i]).getValue()); } pfmc.setCurNumberOfParameters(children.length); pfmc.run(stack); return buildConstantNode(stack.pop()); */ Object val = xj.getEvaluatorVisitor().eval(pfmc, children); return buildConstantNode(val); }
/** Convert to string */ public String toString() { if (simp != null) { return jep.toString(simp); } return jep.toString(node); }
/** Treat the function as complex. */ public void setComplex() { jep.addComplex(); }
public ASTVarNode buildVariableNode(String name, Object value) throws ParseException { return buildVariableNode(xj.getSymbolTable().addVariable(name, value)); }