<html><body style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space; "><div><br></div><div>Hi, </div><div><br></div><div>The mass member in the FourMomentum class sometimes returns NaN, in particularly for the photons. </div><div>Now it's going to be a question for me that how should I consider those values in my analysis ? </div><div><br></div><div><br></div><div><span class="Apple-style-span" style="font-family: monospace, fixed; font-size: 15px; -webkit-border-horizontal-spacing: 2px; -webkit-border-vertical-spacing: 2px; "><pre class="fragment" style="font-family: monospace, fixed; font-size: 14px; border-top-width: 1px; border-right-width: 1px; border-bottom-width: 1px; border-left-width: 1px; border-top-style: solid; border-right-style: solid; border-bottom-style: solid; border-left-style: solid; border-top-color: rgb(204, 204, 204); border-right-color: rgb(204, 204, 204); border-bottom-color: rgb(204, 204, 204); border-left-color: rgb(204, 204, 204); background-color: rgb(245, 245, 245); margin-top: 4px; margin-bottom: 4px; margin-left: 2px; margin-right: 8px; padding-left: 6px; padding-right: 6px; padding-top: 4px; padding-bottom: 4px; position: static; z-index: auto; ">00368 { <a name="l00369" style="text-decoration: none; color: rgb(153, 51, 51); "></a>00369 assert(<a class="code" href="https://projects.hepforge.org/rivet/code/dev/a00346.html#a372c22beaa39783d6a395c422badbc59" style="text-decoration: none; color: rgb(0, 0, 255); font-weight: normal; ">Rivet::isZero</a>(<a class="code" href="https://projects.hepforge.org/rivet/code/dev/a00108.html#a1b9eda3f3f3a13229ab21fa9436a7812" title="Get squared mass (the Lorentz self-invariant)." style="text-decoration: none; color: rgb(0, 0, 255); font-weight: normal; ">mass2</a>()) || <a class="code" href="https://projects.hepforge.org/rivet/code/dev/a00108.html#a1b9eda3f3f3a13229ab21fa9436a7812" title="Get squared mass (the Lorentz self-invariant)." style="text-decoration: none; color: rgb(0, 0, 255); font-weight: normal; ">mass2</a>() > 0); <a name="l00370" style="text-decoration: none; color: rgb(153, 51, 51); "></a>00370 <span class="keywordflow" style="color: rgb(224, 128, 0); ">return</span> sqrt(<a class="code" href="https://projects.hepforge.org/rivet/code/dev/a00108.html#a1b9eda3f3f3a13229ab21fa9436a7812" title="Get squared mass (the Lorentz self-invariant)." style="text-decoration: none; color: rgb(0, 0, 255); font-weight: normal; ">mass2</a>()); <a name="l00371" style="text-decoration: none; color: rgb(153, 51, 51); "></a>00371 }</pre></span></div><div><br></div><div><br></div><div><div><div>Rivet.Analysis.Handler: DEBUG Event #100 weight = 1</div><div>Rivet.Analysis.LHC_2010_EFWDDIFFGAP: DEBUG [mass, mass2, id, E, p] = [0.93957, 0.882792, 2112, 938.54, (0.426217, 0.418899, 938.539)]</div><div>Rivet.Analysis.LHC_2010_EFWDDIFFGAP: DEBUG [mass, mass2, id, E, p] = [0.93957, 0.882792, 2112, 211.161, (0.214592, 0.0281939, 211.159)]</div><div>Rivet.Analysis.LHC_2010_EFWDDIFFGAP: DEBUG [mass, mass2, id, E, p] = [0.49765, 0.247656, 130, 11.0824, (0.516175, -0.0481894, 11.0591)]</div><div>Rivet.Analysis.LHC_2010_EFWDDIFFGAP: DEBUG [mass, mass2, id, E, p] = [0.49765, 0.247656, 130, 5.22922, (-0.123332, -0.202639, 5.20008)]</div><div>Rivet.Analysis.LHC_2010_EFWDDIFFGAP: DEBUG [mass, mass2, id, E, p] = [3.33818e-08, 1.11434e-15, 22, 1.65032, (-0.08561, -0.0331697, 1.64776)]</div><div>Rivet.Analysis.LHC_2010_EFWDDIFFGAP: DEBUG [mass, mass2, id, E, p] = [4.68262e-08, 2.19269e-15, 22, 4.94035, (-0.145798, 0.106414, 4.93705)]</div><div>Rivet.Analysis.LHC_2010_EFWDDIFFGAP: DEBUG [mass, mass2, id, E, p] = [1.60095e-08, 2.56305e-16, 22, 1.45722, (-0.246436, 0.0124048, 1.43617)]</div><div>Rivet.Analysis.LHC_2010_EFWDDIFFGAP: DEBUG [mass, mass2, id, E, p] = [2.52661e-08, 6.38378e-16, 22, 3.71863, (-0.441186, -0.0710671, 3.69168)]</div><div>Rivet.Analysis.LHC_2010_EFWDDIFFGAP: DEBUG [mass, mass2, id, E, p] = [nan, -3.09561e-15, 22, 7.35588, (-0.145765, 0.0699382, 7.3541)]</div><div>Rivet.Analysis.LHC_2010_EFWDDIFFGAP: DEBUG [mass, mass2, id, E, p] = [1.13449e-07, 1.28707e-14, 22, 7.48494, (-0.0504706, -0.0235015, 7.48474)]</div><div>Rivet.Analysis.LHC_2010_EFWDDIFFGAP: DEBUG [mass, mass2, id, E, p] = [nan, -5.82867e-16, 22, 0.710786, (-0.189912, 0.135686, 0.671371)]</div><div>Rivet.Analysis.LHC_2010_EFWDDIFFGAP: DEBUG [mass, mass2, id, E, p] = [1.20236e-05, 1.44567e-10, 22, 487.876, (0.134386, 0.0574909, 487.876)]</div><div>Rivet.Analysis.LHC_2010_EFWDDIFFGAP: DEBUG [mass, mass2, id, E, p] = [nan, -2.1452e-12, 22, 468.457, (-0.00154584, 0.0341641, 468.457)]</div><div>Rivet.Analysis.LHC_2010_EFWDDIFFGAP: DEBUG [mass, mass2, id, E, p] = [8.57925e-06, 7.36036e-11, 22, 411.51, (0.134967, -0.0703667, 411.51)]</div><div>Rivet.Analysis.LHC_2010_EFWDDIFFGAP: DEBUG [mass, mass2, id, E, p] = [1.04885e-07, 1.10008e-14, 22, 1.17373, (-0.00163007, 0.00672073, 1.17371)]</div><div>Rivet.Analysis.LHC_2010_EFWDDIFFGAP: DEBUG [mass, mass2, id, E, p] = [2.12389e-06, 4.51093e-12, 22, 68.9775, (-0.0401148, 0.0518824, 68.9775)]</div><div>Rivet.Analysis.LHC_2010_EFWDDIFFGAP: DEBUG [mass, mass2, id, E, p] = [7.09915e-06, 5.03979e-11, 22, 283.375, (-0.00347369, -0.00781676, 283.375)]</div><div style="font-size: 17px; ">Rivet.Analysis.LHC_2010_EFWDDIFFGAP: DEBUG [mass, mass2, id, E, p] = [nan, -4.27735e-14, 22, 10.7512, (-0.129995, 0.0453852, 10.7503)]</div><div style="font-size: 17px; ">Rivet.Analysis.LHC_2010_EFWDDIFFGAP: DEBUG [mass, mass2, id, E, p] = [nan, -5.52943e-17, 22, 1.50234, (-0.0526513, 0.0431477, 1.5008)]</div><div>Rivet.Analysis.LHC_2010_EFWDDIFFGAP: DEBUG [mass, mass2, id, E, p] = [9.04115e-08, 8.17423e-15, 22, 4.85834, (-0.141602, 0.0259915, 4.85621)]</div><div>Rivet.Analysis.LHC_2010_EFWDDIFFGAP: DEBUG [mass, mass2, id, E, p] = [1.29497e-07, 1.67696e-14, 22, 7.48867, (-0.262596, -0.121533, 7.48308)]</div></div></div><div>Rivet.Analysis.Handler: DEBUG Event #101 weight = 1</div><div><br></div><div><br></div><div><div>Cheers </div><div>Sercan </div></div><div><br></div></body></html>