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items: Bug fixed in PndKinFitter read-in covariance matrix
items: Re: Bug fixed in PndKinFitter read-in covariance matrix

Bug fixed in PndKinFitter read-in covariance matrix
type: item
description: Dear all, I just found a bug in RhoKinFitter::ReadMatrix(), when the original cov matrix is re-arranged from (X, Y, Z, Px, Py, Pz, E) basis to (Px, Py, Pz, E, X, Y, Z). For example, the origianal cov matrix of a photon in (X, Y, Z, Px, Py, Pz, E) is | 0 | 1 | 2 | 3 | 4 | 5 | 6 | --------------------------------------------------------------------------------------------- 0 | 0.2111 0.008221 -0.02881 0.0002914 1.135e-05 -3.977e-05 0 1 | 0.008221 0.2217 0.02912 1.135e-05 0.0003061 4.02e-05 0 2 | -0.02881 0.02912 0.008063 -3.977e-05 4.02e-05 1.113e-05 0 3 | 0.0002914 1.135e-05 -3.977e-05 3.203e-06 -2.683e-06 1.97e-05 2.013e-05 4 | 1.135e-05 0.0003061 4.02e-05 -2.683e-06 3.022e-06 -1.897e-05 -1.939e-05 5 | -3.977e-05 4.02e-05 1.113e-05 1.97e-05 -1.897e-05 0.0001393 0.000142 6 | 0 0 0 2.013e-05 -1.939e-05 0.000142 0.0001447 but the re-arranged one in (Px, Py, Pz, E, X, Y, Z) is | 0 | 1 | 2 | 3 | 4 | 5 | 6 | ---------------------------------------------------------------------------------------------- 0 | 3.203e-06 -2.683e-06 1.97e-05 2.013e-05 1.135e-05 -3.977e-05 0 1 | -2.683e-06 3.022e-06 -1.897e-05 -1.939e-05 0.0003061 4.02e-05 0 2 | 1.97e-05 -1.897e-05 0.0001393 0.000142 4.02e-05 1.113e-05 0 3 | 2.013e-05 -1.939e-05 0.000142 0.0001447 0 0 0 4 | 0.0002914 1.135e-05 -3.977e-05 0 0.2111 0.008221 -0.02881 5 | 1.135e-05 0.0003061 4.02e-05 0 0.008221 0.2217 0.02912 6 | -3.977e-05 4.02e-05 1.113e-05 0 -0.02881 0.02912 0.008063 . One can notice that some elements in the new cov matrix are wrongly filled, eg. the new (0,4) should be equel to the old (3,0)=0.0002914 rather than 1.135e-05. Since the new cov matrix is not symmetric, the whole fitting procedure will be badly influenced. This is caused by a bug in the code: 272 //Change to px,py,pz,E,x,y,z 273 for(int i=0; i<7; i++) { 274 for(int j=0; j<7; j++) { 275 if(i>=3) { 276 if(j>=3) { 277 p4Cov[i-3][j-3] = p3Cov[i][j]; 278 } else { p4Cov[i-3][j+3] = p3Cov[i][j]; } 279 } else { 280 if(j>=3) { 281 p4Cov[i+4][j-3] = p3Cov[i][…
creator: Lu Cao
date: 2016-09-29T14:33:51-00:00

Re: Bug fixed in PndKinFitter read-in covariance matrix
type: item
description: Dear Lu, I changed the line in the repository for you. Great thing you found that bug! Cheers! Ralf
creator: Ralf Kliemt
date: 2016-09-30T07:33:01-00:00

Re: Bug fixed in PndKinFitter read-in covariance matrix
type: item
description: I would be curious to see the difference between probability distributions before and after the bug fix. Could you please provide such plots?
creator: StefanoSpataro
date: 2016-09-30T07:57:39-00:00

Re: Bug fixed in PndKinFitter read-in covariance matrix
type: item
description: Thanks, Ralf. Lu
creator: Lu Cao
date: 2016-09-30T12:41:29-00:00

Re: Bug fixed in PndKinFitter read-in covariance matrix
type: item
description: Hi Stefano, Here's a link of my slides for our group seminar yesterday, which includes the plots you asked for. https://www.dropbox.com/s/hvh6263wqylv46x/lucao_ikp_29092016.pdf?dl=0 I'm going to present the results on the software meeting basically with the same slides. Best, Lu
creator: Lu Cao
date: 2016-09-30T12:47:59-00:00

Re: Bug fixed in PndKinFitter read-in covariance matrix
type: item
description: Hi. As it was pointed out by Jennifer, the same bug was existent in the KinVtxFitter, too. It's fixed now, too (rev. 29531). Cheers! Ralf
creator: Ralf Kliemt
date: 2016-10-06T12:33:55-00:00