| 1 | package de.uka.ipd.sdq.stoex.analyser.operations; |
| 2 | |
| 3 | import java.util.ArrayList; |
| 4 | import java.util.List; |
| 5 | |
| 6 | import de.uka.ipd.sdq.probfunction.math.IProbabilityFunctionFactory; |
| 7 | import de.uka.ipd.sdq.probfunction.math.IProbabilityMassFunction; |
| 8 | import de.uka.ipd.sdq.probfunction.math.ISample; |
| 9 | import de.uka.ipd.sdq.probfunction.math.IUnit; |
| 10 | import de.uka.ipd.sdq.probfunction.math.impl.ProbabilityFunctionFactoryImpl; |
| 11 | |
| 12 | /** |
| 13 | * Abstract class with interface for compare operations (e.g., equals, less, |
| 14 | * etc.). Includes some helper methods for probability functions. |
| 15 | * |
| 16 | * @author koziolek |
| 17 | * |
| 18 | */ |
| 19 | public abstract class CompareOperation { |
| 20 | |
| 21 | private static final Object TRUE_STRING = "true"; |
| 22 | private static final Object FALSE_STRING = "false"; |
| 23 | |
| 24 | /** |
| 25 | * Compares to objects that represent the left-hand side and the right-hand |
| 26 | * side of a comparison expression. |
| 27 | * |
| 28 | * @param left |
| 29 | * @param right |
| 30 | * @return |
| 31 | */ |
| 32 | public IProbabilityMassFunction compare(Object left, Object right) { |
| 33 | |
| 34 | // Assure proper handling of boolean values: |
| 35 | if (left instanceof String) { |
| 36 | if (((String) left).toLowerCase().equals(TRUE_STRING)) { |
| 37 | left = new Boolean(true); |
| 38 | } else if (((String) left).toLowerCase().equals(FALSE_STRING)) { |
| 39 | left = new Boolean(false); |
| 40 | } |
| 41 | } |
| 42 | if (right instanceof String) { |
| 43 | if (((String) right).toLowerCase().equals(TRUE_STRING)) { |
| 44 | right = new Boolean(true); |
| 45 | } else if (((String) right).toLowerCase().equals(FALSE_STRING)) { |
| 46 | right = new Boolean(false); |
| 47 | } |
| 48 | } |
| 49 | |
| 50 | // Propagate to the type-dependent handling: |
| 51 | if ((left instanceof Double) && (right instanceof Double)) { |
| 52 | return getComparePMF((Double) left, (Double) right); |
| 53 | } |
| 54 | if ((left instanceof IProbabilityMassFunction) |
| 55 | && (right instanceof Double)) { |
| 56 | return getComparePMF((IProbabilityMassFunction) left, |
| 57 | (Double) right); |
| 58 | } |
| 59 | if ((left instanceof Double) |
| 60 | && (right instanceof IProbabilityMassFunction)) { |
| 61 | return getComparePMF((Double) left, |
| 62 | (IProbabilityMassFunction) right); |
| 63 | } |
| 64 | if ((left instanceof IProbabilityMassFunction) |
| 65 | && (right instanceof IProbabilityMassFunction)) { |
| 66 | return getComparePMF((IProbabilityMassFunction) left, |
| 67 | (IProbabilityMassFunction) right); |
| 68 | } |
| 69 | if ((left instanceof String) && (right instanceof String)) { |
| 70 | return getComparePMF((String) left, (String) right); |
| 71 | } |
| 72 | if ((left instanceof String) |
| 73 | && (right instanceof IProbabilityMassFunction)) { |
| 74 | return getComparePMF((String) left, |
| 75 | (IProbabilityMassFunction) right); |
| 76 | } |
| 77 | if ((left instanceof Boolean) && (right instanceof Boolean)) { |
| 78 | return getComparePMF((Boolean) left, (Boolean) right); |
| 79 | } |
| 80 | |
| 81 | // Type not supported: |
| 82 | throw new UnsupportedOperationException(); |
| 83 | } |
| 84 | |
| 85 | /** |
| 86 | * Compares two probability mass functions pointwise. |
| 87 | * |
| 88 | * @param left |
| 89 | * @param right |
| 90 | * @return |
| 91 | */ |
| 92 | public double comparePointWise(IProbabilityMassFunction left, |
| 93 | IProbabilityMassFunction right, CompareOperation op) { |
| 94 | List<ISample> samplingPointsLeft = left.getSamples(); |
| 95 | List<ISample> samplingPointsRight = right.getSamples(); |
| 96 | double probabilitySum = 0.0; |
| 97 | for (ISample leftSamplingPoint : samplingPointsLeft) { |
| 98 | Object leftValue = leftSamplingPoint.getValue(); |
| 99 | for (ISample rightSamplingPoint : samplingPointsRight) { |
| 100 | Object rightValue = rightSamplingPoint.getValue(); |
| 101 | IProbabilityMassFunction boolPMF = op.compare(leftValue, |
| 102 | rightValue); |
| 103 | if ((Double) boolPMF.getSamples().get(1).getProbability() == 1.0) { |
| 104 | probabilitySum += leftSamplingPoint.getProbability() |
| 105 | * rightSamplingPoint.getProbability(); |
| 106 | } |
| 107 | } |
| 108 | } |
| 109 | return probabilitySum; |
| 110 | } |
| 111 | |
| 112 | /** |
| 113 | * Converts a probability into a boolean PMF. The probability is taken as |
| 114 | * value for true and 1-probability as value for false. |
| 115 | * |
| 116 | * @param left |
| 117 | * @param right |
| 118 | * @return |
| 119 | */ |
| 120 | public IProbabilityMassFunction getBoolPMF(double trueProb) { |
| 121 | IProbabilityFunctionFactory probFac = IProbabilityFunctionFactory.eINSTANCE; |
| 122 | |
| 123 | IUnit unit = probFac.createUnit("bool"); |
| 124 | |
| 125 | List<ISample> sampleList = new ArrayList<ISample>(); |
| 126 | sampleList.add(probFac.createSample(TRUE_STRING, trueProb)); |
| 127 | sampleList.add(probFac.createSample(FALSE_STRING, 1 - trueProb)); |
| 128 | |
| 129 | IProbabilityMassFunction boolPMF = probFac |
| 130 | .createProbabilityMassFunction(sampleList, unit, true); |
| 131 | |
| 132 | return boolPMF; |
| 133 | } |
| 134 | |
| 135 | /** |
| 136 | * Retrieves the probability for a given value from a PMF. |
| 137 | * |
| 138 | * @param iPMF |
| 139 | * @param valueToSeek |
| 140 | * @return |
| 141 | */ |
| 142 | public double getProbabilityForValue(IProbabilityMassFunction iPMF, |
| 143 | double valueToSeek) { |
| 144 | List<ISample> samplingPoints = iPMF.getSamples(); |
| 145 | for (ISample samplingPoint : samplingPoints) { |
| 146 | Object value = samplingPoint.getValue(); |
| 147 | if (value instanceof Number) { |
| 148 | Number valueNumber = (Number) samplingPoint.getValue(); |
| 149 | if (valueNumber.doubleValue() == valueToSeek) { |
| 150 | return samplingPoint.getProbability(); |
| 151 | } |
| 152 | } |
| 153 | } |
| 154 | return 0.0; |
| 155 | } |
| 156 | |
| 157 | /** |
| 158 | * Returns the sum of probabilities before a given value of a PMF. |
| 159 | * |
| 160 | * @param iPMF |
| 161 | * @param threshold |
| 162 | * @param includeThreshold |
| 163 | * @return |
| 164 | */ |
| 165 | public double getThresholdProbability(IProbabilityMassFunction iPMF, |
| 166 | double threshold, boolean includeThreshold) { |
| 167 | double probabilitySum = 0.0; |
| 168 | for (ISample sample : iPMF.getSamples()) { |
| 169 | Object sampleValueObject = sample.getValue(); |
| 170 | if (sampleValueObject instanceof Number) { |
| 171 | Double sampleValue = ((Number) sampleValueObject).doubleValue(); |
| 172 | if (sampleValue > threshold) { |
| 173 | return probabilitySum; |
| 174 | } else if (sampleValue == threshold) { |
| 175 | return (includeThreshold) ? probabilitySum |
| 176 | + sample.getProbability() : probabilitySum; |
| 177 | } else { |
| 178 | probabilitySum += sample.getProbability(); |
| 179 | } |
| 180 | } else |
| 181 | throw new UnsupportedOperationException(); |
| 182 | } |
| 183 | return 0.0; |
| 184 | } |
| 185 | |
| 186 | /** |
| 187 | * Compares two boolean values. |
| 188 | * |
| 189 | * @param left |
| 190 | * @param right |
| 191 | * @return |
| 192 | */ |
| 193 | protected abstract IProbabilityMassFunction getComparePMF(boolean left, |
| 194 | boolean right); |
| 195 | |
| 196 | /** |
| 197 | * Compares two doubles. |
| 198 | * |
| 199 | * @param left |
| 200 | * @param right |
| 201 | * @return |
| 202 | */ |
| 203 | protected abstract IProbabilityMassFunction getComparePMF(double left, |
| 204 | double right); |
| 205 | |
| 206 | /** |
| 207 | * Compares a PMF with a double. |
| 208 | * |
| 209 | * @param left |
| 210 | * @param right |
| 211 | * @return |
| 212 | */ |
| 213 | protected abstract IProbabilityMassFunction getComparePMF(double left, |
| 214 | IProbabilityMassFunction right); |
| 215 | |
| 216 | /** |
| 217 | * Compares a PMF with a double. |
| 218 | * |
| 219 | * @param left |
| 220 | * @param right |
| 221 | * @return |
| 222 | */ |
| 223 | protected abstract IProbabilityMassFunction getComparePMF( |
| 224 | IProbabilityMassFunction left, double right); |
| 225 | |
| 226 | /** |
| 227 | * Compares two PMFs. |
| 228 | * |
| 229 | * @param left |
| 230 | * @param right |
| 231 | * @return |
| 232 | */ |
| 233 | protected abstract IProbabilityMassFunction getComparePMF( |
| 234 | IProbabilityMassFunction left, IProbabilityMassFunction right); |
| 235 | |
| 236 | /** |
| 237 | * Compares a String and an EnumPMF |
| 238 | * |
| 239 | * @param left |
| 240 | * @param right |
| 241 | * @return |
| 242 | */ |
| 243 | protected abstract IProbabilityMassFunction getComparePMF(String left, |
| 244 | IProbabilityMassFunction right); |
| 245 | |
| 246 | /** |
| 247 | * Compares two Strings. |
| 248 | * |
| 249 | * @param left |
| 250 | * @param right |
| 251 | * @return |
| 252 | */ |
| 253 | protected abstract IProbabilityMassFunction getComparePMF(String left, |
| 254 | String right); |
| 255 | |
| 256 | /** |
| 257 | * This method inverts a BoolPMF as required by a NOT statement. |
| 258 | * This method would be better placed elsewhere, but it accesses internal knowledge how |
| 259 | * a BoolPMF is represented as a IProbabilityMassFunction which is only available in this class. |
| 260 | * @see #getBoolPMF(double). |
| 261 | * @param function |
| 262 | * @return The inverted function, assuming this is a BoolPMF. |
| 263 | * @throws UnsupportedOperationException if the passed PMF is not a BoolPMF, |
| 264 | * i.e. if it does not contain the String literals "TRUE" and "FALSE". |
| 265 | */ |
| 266 | public static IProbabilityMassFunction invertBoolPMF(IProbabilityMassFunction function){ |
| 267 | //check whether this is a BoolPMF, i.e. two samples with labels TRUE and FALSE. |
| 268 | List<ISample> samples = function.getSamples(); |
| 269 | if (samples.size() == 2){ |
| 270 | ISample sample1 = samples.get(0); |
| 271 | ISample sample2 = samples.get(1); |
| 272 | |
| 273 | ISample sampleTrue = null; |
| 274 | ISample sampleFalse = null; |
| 275 | |
| 276 | if (sampleIsTrue(sample1)){ |
| 277 | if (sampleIsFalse(sample2)){ |
| 278 | sampleTrue = sample1; |
| 279 | sampleFalse = sample2; |
| 280 | } |
| 281 | } else if (sampleIsFalse(sample1)){ |
| 282 | if (sampleIsTrue(sample2)){ |
| 283 | sampleTrue = sample2; |
| 284 | sampleFalse = sample1; |
| 285 | } |
| 286 | } |
| 287 | |
| 288 | if (sampleTrue != null && sampleFalse != null){ |
| 289 | |
| 290 | IProbabilityFunctionFactory probFac = ProbabilityFunctionFactoryImpl.eINSTANCE; |
| 291 | |
| 292 | //is probably never used. |
| 293 | IUnit unit = probFac.createUnit("bool"); |
| 294 | |
| 295 | List<ISample> sampleList = new ArrayList<ISample>(); |
| 296 | |
| 297 | ISample newTrueSample = probFac.createSample(true, sampleFalse.getProbability()); |
| 298 | ISample newFalseSample = probFac.createSample(false, sampleTrue.getProbability()); |
| 299 | sampleList.add(newTrueSample); |
| 300 | sampleList.add(newFalseSample); |
| 301 | |
| 302 | IProbabilityMassFunction boolPMF = probFac |
| 303 | .createProbabilityMassFunction(sampleList, unit, true); |
| 304 | |
| 305 | return boolPMF; |
| 306 | |
| 307 | } |
| 308 | } |
| 309 | throw new UnsupportedOperationException("Cannot invert PMF "+function.toString()+" as it is no valid BoolPMF."); |
| 310 | } |
| 311 | |
| 312 | private static boolean sampleIsTrue(ISample sample) { |
| 313 | if (sample.getValue() instanceof Boolean) |
| 314 | return (Boolean)sample.getValue(); |
| 315 | return TRUE_STRING.equals(sample.getValue()); |
| 316 | } |
| 317 | |
| 318 | private static boolean sampleIsFalse(ISample sample) { |
| 319 | if (sample.getValue() instanceof Boolean) |
| 320 | return !(Boolean)sample.getValue(); |
| 321 | return FALSE_STRING.equals(sample.getValue()); |
| 322 | } |
| 323 | } |