src/FDM/JSBSim/input_output/FGXMLElement.cpp

   1 /*%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
   2
   3  Author:       Jon Berndt
   4  Date started: 09/28/2004
   5  Purpose:      XML element class
   6  Called by:    FGXMLParse
   7
   8  ------------- Copyright (C) 2001  Jon S. Berndt (jon@jsbsim.org) -------------
   9
  10  This program is free software; you can redistribute it and/or modify it under
  11  the terms of the GNU Lesser General Public License as published by the Free Software
  12  Foundation; either version 2 of the License, or (at your option) any later
  13  version.
  14
  15  This program is distributed in the hope that it will be useful, but WITHOUT
  16  ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
  17  FOR A PARTICULAR PURPOSE.  See the GNU Lesser General Public License for more
  18  details.
  19
  20  You should have received a copy of the GNU Lesser General Public License along with
  21  this program; if not, write to the Free Software Foundation, Inc., 59 Temple
  22  Place - Suite 330, Boston, MA  02111-1307, USA.
  23
  24  Further information about the GNU Lesser General Public License can also be found on
  25  the world wide web at http://www.gnu.org.
  26
  27 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
  28 INCLUDES
  29 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%*/
  30
  31 #include "FGXMLElement.h"
  32
  33 #include <cmath>
  34 #include <cstdlib>
  35 #include <iostream>
  36
  37 using namespace std;
  38
  39 /*%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
  40 FORWARD DECLARATIONS
  41 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%*/
  42
  43 namespace JSBSim {
  44
  45 static const char *IdSrc = "$Id$";
  46 static const char *IdHdr = ID_XMLELEMENT;
  47
  48 bool Element::converterIsInitialized = false;
  49 map <string, map <string, double> > Element::convert;
  50
  51 /*%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
  52 CLASS IMPLEMENTATION
  53 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%*/
  54
  55 Element::Element(const string& nm)
  56 {
  57   name   = nm;
  58   parent = 0L;
  59   element_index = 0;
  60
  61   if (!converterIsInitialized) {
  62     converterIsInitialized = true;
  63     // convert ["from"]["to"] = factor, so: from * factor = to
  64     // Length
  65     convert["M"]["FT"] = 3.2808399;
  66     convert["FT"]["M"] = 1.0/convert["M"]["FT"];
  67     convert["FT"]["IN"] = 12.0;
  68     convert["IN"]["FT"] = 1.0/convert["FT"]["IN"];
  69     convert["IN"]["M"] = convert["IN"]["FT"] * convert["FT"]["M"];
  70     convert["M"]["IN"] = convert["M"]["FT"] * convert["FT"]["IN"];
  71     // Area
  72     convert["M2"]["FT2"] = convert["M"]["FT"]*convert["M"]["FT"];
  73     convert["FT2"]["M2"] = 1.0/convert["M2"]["FT2"];
  74     convert["M2"]["IN2"] = convert["M"]["IN"]*convert["M"]["IN"];
  75     convert["IN2"]["M2"] = 1.0/convert["M2"]["IN2"];
  76     convert["FT2"]["IN2"] = 144.0;
  77     convert["IN2"]["FT2"] = 1.0/convert["FT2"]["IN2"];
  78     // Volume
  79     convert["IN3"]["CC"] = 16.387064;
  80     convert["CC"]["IN3"] = 1.0/convert["IN3"]["CC"];
  81     convert["FT3"]["IN3"] = 1728.0;
  82     convert["IN3"]["FT3"] = 1.0/convert["FT3"]["IN3"];
  83     convert["M3"]["FT3"] = 35.3146667;
  84     convert["FT3"]["M3"] = 1.0/convert["M3"]["FT3"];
  85     convert["LTR"]["IN3"] = 61.0237441;
  86     convert["IN3"]["LTR"] = 1.0/convert["LTR"]["IN3"];
  87     // Mass & Weight
  88     convert["LBS"]["KG"] = 0.45359237;
  89     convert["KG"]["LBS"] = 1.0/convert["LBS"]["KG"];
  90     convert["SLUG"]["KG"] = 14.59390;
  91     convert["KG"]["SLUG"] = 1.0/convert["SLUG"]["KG"];
  92     // Moments of Inertia
  93     convert["SLUG*FT2"]["KG*M2"] = 1.35594;
  94     convert["KG*M2"]["SLUG*FT2"] = 1.0/convert["SLUG*FT2"]["KG*M2"];
  95     // Angles
  96     convert["RAD"]["DEG"] = 360.0/(2.0*3.1415926);
  97     convert["DEG"]["RAD"] = 1.0/convert["RAD"]["DEG"];
  98     // Spring force
  99     convert["LBS/FT"]["N/M"] = 14.5939;
 100     convert["N/M"]["LBS/FT"] = 1.0/convert["LBS/FT"]["N/M"];
 101     // Damping force
 102     convert["LBS/FT/SEC"]["N/M/SEC"] = 14.5939;
 103     convert["N/M/SEC"]["LBS/FT/SEC"] = 1.0/convert["LBS/FT/SEC"]["N/M/SEC"];
 104     // Damping force (Square Law)
 105     convert["LBS/FT2/SEC2"]["N/M2/SEC2"] = 47.880259;
 106     convert["N/M2/SEC2"]["LBS/FT2/SEC2"] = 1.0/convert["LBS/FT2/SEC2"]["N/M2/SEC2"];
 107     // Power
 108     convert["WATTS"]["HP"] = 0.001341022;
 109     convert["HP"]["WATTS"] = 1.0/convert["WATTS"]["HP"];
 110     // Force
 111     convert["N"]["LBS"] = 0.22482;
 112     convert["LBS"]["N"] = 1.0/convert["N"]["LBS"];
 113     // Velocity
 114     convert["KTS"]["FT/SEC"] = 1.68781;
 115     convert["FT/SEC"]["KTS"] = 1.0/convert["KTS"]["FT/SEC"];
 116     convert["M/S"]["FT/S"] = 3.2808399;
 117     convert["FT/S"]["M/S"] = 1.0/convert["M/S"]["FT/S"];
 118     // Torque
 119     convert["FT*LBS"]["N*M"] = 1.35581795;
 120     convert["N*M"]["FT*LBS"] = 1/convert["FT*LBS"]["N*M"];
 121     // Valve
 122     convert["M4*SEC/KG"]["FT4*SEC/SLUG"] = convert["M"]["FT"]*convert["M"]["FT"]*
 123       convert["M"]["FT"]*convert["M"]["FT"]/convert["KG"]["SLUG"];
 124     convert["FT4*SEC/SLUG"]["M4*SEC/KG"] =
 125       1.0/convert["M4*SEC/KG"]["FT4*SEC/SLUG"];
 126     // Pressure
 127     convert["INHG"]["PSF"] = 70.7180803;
 128     convert["PSF"]["INHG"] = 1.0/convert["INHG"]["PSF"];
 129     convert["ATM"]["INHG"] = 29.9246899;
 130     convert["INHG"]["ATM"] = 1.0/convert["ATM"]["INHG"];
 131     convert["PSI"]["INHG"] = 2.03625437;
 132     convert["INHG"]["PSI"] = 1.0/convert["PSI"]["INHG"];
 133     convert["INHG"]["PA"] = 3386.0; // inches Mercury to pascals
 134     convert["PA"]["INHG"] = 1.0/convert["INHG"]["PA"];
 135     convert["LBS/FT2"]["N/M2"] = 14.5939/convert["FT"]["M"];
 136     convert["N/M2"]["LBS/FT2"] = 1.0/convert["LBS/FT2"]["N/M2"];
 137     convert["LBS/FT2"]["PA"] = convert["LBS/FT2"]["N/M2"];
 138     convert["PA"]["LBS/FT2"] = 1.0/convert["LBS/FT2"]["PA"];
 139     // Mass flow
 140     convert["KG/MIN"]["LBS/MIN"] = convert["KG"]["LBS"];
 141     // Fuel Consumption
 142     convert["LBS/HP*HR"]["KG/KW*HR"] = 0.6083;
 143     convert["KG/KW*HR"]["LBS/HP*HR"] = 1.0/convert["LBS/HP*HR"]["KG/KW*HR"];
 144     // Density
 145     convert["KG/L"]["LBS/GAL"] = 8.3454045;
 146     convert["LBS/GAL"]["KG/L"] = 1.0/convert["KG/L"]["LBS/GAL"];
 147
 148     // Length
 149     convert["M"]["M"] = 1.00;
 150     convert["FT"]["FT"] = 1.00;
 151     convert["IN"]["IN"] = 1.00;
 152     // Area
 153     convert["M2"]["M2"] = 1.00;
 154     convert["FT2"]["FT2"] = 1.00;
 155     // Volume
 156     convert["IN3"]["IN3"] = 1.00;
 157     convert["CC"]["CC"] = 1.0;
 158     convert["M3"]["M3"] = 1.0;
 159     convert["FT3"]["FT3"] = 1.0;
 160     convert["LTR"]["LTR"] = 1.0;
 161     // Mass & Weight
 162     convert["KG"]["KG"] = 1.00;
 163     convert["LBS"]["LBS"] = 1.00;
 164     // Moments of Inertia
 165     convert["KG*M2"]["KG*M2"] = 1.00;
 166     convert["SLUG*FT2"]["SLUG*FT2"] = 1.00;
 167     // Angles
 168     convert["DEG"]["DEG"] = 1.00;
 169     convert["RAD"]["RAD"] = 1.00;
 170     // Spring force
 171     convert["LBS/FT"]["LBS/FT"] = 1.00;
 172     convert["N/M"]["N/M"] = 1.00;
 173     // Damping force
 174     convert["LBS/FT/SEC"]["LBS/FT/SEC"] = 1.00;
 175     convert["N/M/SEC"]["N/M/SEC"] = 1.00;
 176     // Damping force (Square law)
 177     convert["LBS/FT2/SEC2"]["LBS/FT2/SEC2"] = 1.00;
 178     convert["N/M2/SEC2"]["N/M2/SEC2"] = 1.00;
 179     // Power
 180     convert["HP"]["HP"] = 1.00;
 181     convert["WATTS"]["WATTS"] = 1.00;
 182     // Force
 183     convert["N"]["N"] = 1.00;
 184     // Velocity
 185     convert["FT/SEC"]["FT/SEC"] = 1.00;
 186     convert["KTS"]["KTS"] = 1.00;
 187     convert["M/S"]["M/S"] = 1.0;
 188     // Torque
 189     convert["FT*LBS"]["FT*LBS"] = 1.00;
 190     convert["N*M"]["N*M"] = 1.00;
 191     // Valve
 192     convert["M4*SEC/KG"]["M4*SEC/KG"] = 1.0;
 193     convert["FT4*SEC/SLUG"]["FT4*SEC/SLUG"] = 1.0;
 194     // Pressure
 195     convert["PSI"]["PSI"] = 1.00;
 196     convert["PSF"]["PSF"] = 1.00;
 197     convert["INHG"]["INHG"] = 1.00;
 198     convert["ATM"]["ATM"] = 1.0;
 199     convert["PA"]["PA"] = 1.0;
 200     convert["N/M2"]["N/M2"] = 1.00;
 201     convert["LBS/FT2"]["LBS/FT2"] = 1.00;
 202     // Mass flow
 203     convert["LBS/SEC"]["LBS/SEC"] = 1.00;
 204     convert["KG/MIN"]["KG/MIN"] = 1.0;
 205     convert["LBS/MIN"]["LBS/MIN"] = 1.0;
 206     // Fuel Consumption
 207     convert["LBS/HP*HR"]["LBS/HP*HR"] = 1.0;
 208     convert["KG/KW*HR"]["KG/KW*HR"] = 1.0;
 209     // Density
 210     convert["KG/L"]["KG/L"] = 1.0;
 211     convert["LBS/GAL"]["LBS/GAL"] = 1.0;
 212   }
 213 }
 214
 215 //%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 216
 217 Element::~Element(void)
 218 {
 219   for (unsigned int i=0; i<children.size(); i++) delete children[i];
 220   data_lines.clear();
 221   attributes.clear();
 222   attribute_key.clear();
 223 }
 224
 225 //%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 226
 227 string Element::GetAttributeValue(const string& attr)
 228 {
 229   int select=-1;
 230   for (unsigned int i=0; i<attribute_key.size(); i++) {
 231     if (attribute_key[i] == attr) select = i;
 232   }
 233   if (select < 0) return string("");
 234   else return attributes[attr];
 235 }
 236
 237 //%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 238
 239 double Element::GetAttributeValueAsNumber(const string& attr)
 240 {
 241   string attribute = GetAttributeValue(attr);
 242
 243   if (attribute.empty()) return HUGE_VAL;
 244   else return (atof(attribute.c_str()));
 245 }
 246
 247 //%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 248
 249 Element* Element::GetElement(unsigned int el)
 250 {
 251   if (children.size() > el) {
 252     element_index = el;
 253     return children[el];
 254   }
 255   else {
 256     element_index = 0;
 257     return 0L;
 258   }
 259 }
 260
 261 //%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 262
 263 Element* Element::GetNextElement(void)
 264 {
 265   if (children.size() > element_index+1) {
 266     element_index++;
 267     return children[element_index];
 268   } else {
 269     element_index = 0;
 270     return 0L;
 271   }
 272 }
 273
 274 //%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 275
 276 string Element::GetDataLine(unsigned int i)
 277 {
 278   if (data_lines.size() > 0) return data_lines[i];
 279   else return string("");
 280 }
 281
 282 //%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 283
 284 double Element::GetDataAsNumber(void)
 285 {
 286   if (data_lines.size() == 1) {
 287     return atof(data_lines[0].c_str());
 288   } else if (data_lines.size() == 0) {
 289     return HUGE_VAL;
 290   } else {
 291     cerr << "Attempting to get single data value from multiple lines in element " << name << endl;
 292     return HUGE_VAL;
 293   }
 294 }
 295
 296 //%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 297
 298 unsigned int Element::GetNumElements(const string& element_name)
 299 {
 300   unsigned int number_of_elements=0;
 301   Element* el=FindElement(element_name);
 302   while (el) {
 303     number_of_elements++;
 304     el=FindNextElement(element_name);
 305   }
 306   return number_of_elements;
 307 }
 308
 309 //%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 310
 311 Element* Element::FindElement(const string& el)
 312 {
 313   if (el.empty() && children.size() >= 1) {
 314     element_index = 1;
 315     return children[0];
 316   }
 317   for (unsigned int i=0; i<children.size(); i++) {
 318     if (el == children[i]->GetName()) {
 319       element_index = i+1;
 320       return children[i];
 321     }
 322   }
 323   element_index = 0;
 324   return 0L;
 325 }
 326
 327 //%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 328
 329 Element* Element::FindNextElement(const string& el)
 330 {
 331   if (el.empty()) {
 332     if (element_index < children.size()) {
 333       return children[element_index++];
 334     } else {
 335       element_index = 0;
 336       return 0L;
 337     }
 338   }
 339   for (unsigned int i=element_index; i<children.size(); i++) {
 340     if (el == children[i]->GetName()) {
 341       element_index = i+1;
 342       return children[i];
 343     }
 344   }
 345   element_index = 0;
 346   return 0L;
 347 }
 348
 349 //%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 350
 351 double Element::FindElementValueAsNumber(const string& el)
 352 {
 353   Element* element = FindElement(el);
 354   if (element) {
 355     return element->GetDataAsNumber();
 356   } else {
 357     cerr << "Attempting to get single data value from multiple lines" << endl;
 358     return 0;
 359   }
 360 }
 361
 362 //%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 363
 364 string Element::FindElementValue(const string& el)
 365 {
 366   Element* element = FindElement(el);
 367   if (element) {
 368     return element->GetDataLine();
 369   } else {
 370     return "";
 371   }
 372 }
 373
 374 //%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 375
 376 double Element::FindElementValueAsNumberConvertTo(const string& el, const string& target_units)
 377 {
 378   Element* element = FindElement(el);
 379
 380   if (!element) {
 381     cerr << "Attempting to get non-existent element " << el << endl;
 382     exit(0);
 383   }
 384
 385   string supplied_units = element->GetAttributeValue("unit");
 386
 387   if (!supplied_units.empty()) {
 388     if (convert.find(supplied_units) == convert.end()) {
 389       cerr << endl << "Supplied unit: \"" << supplied_units << "\" does not exist (typo?). Add new unit"
 390            << " conversion in FGXMLElement.cpp." << endl;
 391       exit(-1);
 392     }
 393     if (convert[supplied_units].find(target_units) == convert[supplied_units].end()) {
 394       cerr << endl << "Supplied unit: \"" << supplied_units << "\" cannot be converted to "
 395                    << target_units << ". Add new unit conversion in FGXMLElement.cpp or fix typo" << endl;
 396       exit(-1);
 397     }
 398   }
 399
 400   double value = element->GetDataAsNumber();
 401   if (!supplied_units.empty()) {
 402     value *= convert[supplied_units][target_units];
 403   }
 404
 405   return value;
 406 }
 407
 408 //%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 409
 410 double Element::FindElementValueAsNumberConvertFromTo( const string& el,
 411                                                        const string& supplied_units,
 412                                                        const string& target_units)
 413 {
 414   Element* element = FindElement(el);
 415
 416   if (!element) {
 417     cerr << "Attempting to get non-existent element " << el << endl;
 418     exit(0);
 419   }
 420
 421   if (!supplied_units.empty()) {
 422     if (convert.find(supplied_units) == convert.end()) {
 423       cerr << endl << "Supplied unit: \"" << supplied_units << "\" does not exist (typo?). Add new unit"
 424            << " conversion in FGXMLElement.cpp." << endl;
 425       exit(-1);
 426     }
 427     if (convert[supplied_units].find(target_units) == convert[supplied_units].end()) {
 428       cerr << endl << "Supplied unit: \"" << supplied_units << "\" cannot be converted to "
 429                    << target_units << ". Add new unit conversion in FGXMLElement.cpp or fix typo" << endl;
 430       exit(-1);
 431     }
 432   }
 433
 434   double value = element->GetDataAsNumber();
 435   if (!supplied_units.empty()) {
 436     value *= convert[supplied_units][target_units];
 437   }
 438
 439   return value;
 440 }
 441
 442 //%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 443
 444 FGColumnVector3 Element::FindElementTripletConvertTo( const string& target_units)
 445 {
 446   FGColumnVector3 triplet;
 447   Element* item;
 448   double value=0.0;
 449   string supplied_units = GetAttributeValue("unit");
 450
 451   if (!supplied_units.empty()) {
 452     if (convert.find(supplied_units) == convert.end()) {
 453       cerr << endl << "Supplied unit: \"" << supplied_units << "\" does not exist (typo?). Add new unit"
 454            << " conversion in FGXMLElement.cpp." << endl;
 455       exit(-1);
 456     }
 457     if (convert[supplied_units].find(target_units) == convert[supplied_units].end()) {
 458       cerr << endl << "Supplied unit: \"" << supplied_units << "\" cannot be converted to "
 459                    << target_units << ". Add new unit conversion in FGXMLElement.cpp or fix typo" << endl;
 460       exit(-1);
 461     }
 462   }
 463
 464   item = FindElement("x");
 465   if (!item) item = FindElement("roll");
 466   if (item) {
 467     value = item->GetDataAsNumber();
 468     if (!supplied_units.empty()) value *= convert[supplied_units][target_units];
 469   } else {
 470     value = 0.0;
 471     cerr << "Could not find an X triplet item for this column vector." << endl;
 472   }
 473   triplet(1) = value;
 474
 475   item = FindElement("y");
 476   if (!item) item = FindElement("pitch");
 477   if (item) {
 478     value = item->GetDataAsNumber();
 479     if (!supplied_units.empty()) value *= convert[supplied_units][target_units];
 480   } else {
 481     value = 0.0;
 482     cerr << "Could not find a Y triplet item for this column vector." << endl;
 483   }
 484   triplet(2) = value;
 485
 486   item = FindElement("z");
 487   if (!item) item = FindElement("yaw");
 488   if (item) {
 489     value = item->GetDataAsNumber();
 490     if (!supplied_units.empty()) value *= convert[supplied_units][target_units];
 491   } else {
 492     value = 0.0;
 493     cerr << "Could not find a Z triplet item for this column vector." << endl;
 494   }
 495   triplet(3) = value;
 496
 497   return triplet;
 498 }
 499
 500 //%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 501
 502 void Element::Print(unsigned int level)
 503 {
 504   unsigned int i, spaces;
 505
 506   level+=2;
 507   for (spaces=0; spaces<=level; spaces++) cout << " "; // format output
 508   cout << "Element Name: " << name;
 509   for (i=0; i<attributes.size(); i++) {
 510     cout << "  " << attribute_key[i] << " = " << attributes[attribute_key[i]];
 511   }
 512   cout << endl;
 513   for (i=0; i<data_lines.size(); i++) {
 514     for (spaces=0; spaces<=level; spaces++) cout << " "; // format output
 515     cout << data_lines[i] << endl;
 516   }
 517   for (i=0; i<children.size(); i++) {
 518     children[i]->Print(level);
 519   }
 520 }
 521
 522 //%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 523
 524 void Element::AddAttribute(const string& name, const string& value)
 525 {
 526   attribute_key.push_back(name);
 527   attributes[name] = value;
 528 }
 529
 530 //%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 531
 532 void Element::AddData(string d)
 533 {
 534   string::size_type string_start = d.find_first_not_of(" \t");
 535   if (string_start != string::npos && string_start > 0) {
 536     d.erase(0,string_start);
 537   }
 538   data_lines.push_back(d);
 539 }
 540
 541 //%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 542
 543 } // end namespace JSBSim