In [10]:
tr->Draw("rhit");
c1->Draw();
描述一个粒子与DSSD的相互作用，需要如下信息：
常用的数据表达方式为数组，假设有三个DSSD(128x128)：
Int_t xe[3][128], ye[3][128];//raw
Double_t xec[3][128], yec[3][128]; //calibrated
Int_t xt[3][128], yt[3][128];//raw
Double_t xtc[3][128], yec[3][128]; //calibrated
而在绝大多数情况下，一个DSSD只有少数条包含有用的信息，数组中大多数元素是无用的。
固定数组的记录方式导致内存和空间的浪费。
另外数组结构不利于表达DSSD的整体特性，如无法一次检查一个DSSD中多个条的能量信息。
//%jsroot on
TFile *f = new TFile("s4.root");
TTree *tree = (TTree*)f->Get("tree");
TCanvas *c1 = new TCanvas;
tree->Scan("pe:re", "", "", 1, 1);//第4参数-事件数，第5参数-起始事件编号
//jupyter上的Scan必须指定第4个参数(事件数)
*********************************************** * Row * Instance * pe * re * *********************************************** * 1 * 0 * -10 * -10 * * 1 * 1 * -10 * -10 * * 1 * 2 * -10 * -10 * * 1 * 3 * -10 * -10 * * 1 * 4 * -10 * -10 * * 1 * 5 * -10 * -10 * * 1 * 6 * -10 * -10 * * 1 * 7 * -10 * -10 * * 1 * 8 * -10 * -10 * * 1 * 9 * -10 * -10 * * 1 * 10 * 983 * -10 * * 1 * 11 * -10 * -10 * * 1 * 12 * -10 * -10 * * 1 * 13 * -10 * -10 * * 1 * 14 * -10 * -10 * * 1 * 15 * -10 * -10 * * 1 * 16 * -10 * -10 * * 1 * 17 * -10 * -10 * * 1 * 18 * -10 * -10 * * 1 * 19 * -10 * -10 * * 1 * 20 * -10 * -10 * * 1 * 21 * -10 * -10 * * 1 * 22 * -10 * -10 * * 1 * 23 * -10 * -10 * * 1 * 24 * -10 * -10 * * 1 * 25 * -10 * -10 * * 1 * 26 * -10 * -10 * * 1 * 27 * -10 * -10 * * 1 * 28 * -10 * -10 * * 1 * 29 * -10 * -10 * * 1 * 30 * -10 * -10 * * 1 * 31 * -10 * -10 * * 1 * 32 * -10 * -10 * * 1 * 33 * -10 * -10 * * 1 * 34 * -10 * -10 * * 1 * 35 * -10 * -10 * * 1 * 36 * -10 * -10 * * 1 * 37 * -10 * -10 * * 1 * 38 * -10 * -10 * * 1 * 39 * -10 * -10 * * 1 * 40 * -10 * -10 * * 1 * 41 * -10 * -10 * * 1 * 42 * -10 * -10 * * 1 * 43 * -10 * -10 * * 1 * 44 * -10 * -10 * * 1 * 45 * -10 * -10 * * 1 * 46 * -10 * -10 * * 1 * 47 * -10 * -10 * ***********************************************
Type <CR> to continue or q to quit ==>
tree->Scan("pe:re", "", "", 1, 2);
*********************************************** * Row * Instance * pe * re * *********************************************** * 2 * 0 * -10 * -10 * * 2 * 1 * -10 * -10 * * 2 * 2 * -10 * -10 * * 2 * 3 * -10 * -10 * * 2 * 4 * -10 * -10 * * 2 * 5 * -10 * -10 * * 2 * 6 * -10 * -10 * * 2 * 7 * -10 * -10 * * 2 * 8 * 978 * -10 * * 2 * 9 * -10 * -10 * * 2 * 10 * -10 * -10 * * 2 * 11 * -10 * -10 * * 2 * 12 * -10 * -10 * * 2 * 13 * -10 * -10 * * 2 * 14 * -10 * -10 * * 2 * 15 * -10 * -10 * * 2 * 16 * -10 * -10 * * 2 * 17 * -10 * -10 * * 2 * 18 * -10 * -10 * * 2 * 19 * -10 * -10 * * 2 * 20 * -10 * -10 * * 2 * 21 * -10 * -10 * * 2 * 22 * -10 * -10 * * 2 * 23 * -10 * -10 * * 2 * 24 * -10 * -10 * * 2 * 25 * -10 * -10 * * 2 * 26 * -10 * -10 * * 2 * 27 * -10 * -10 * * 2 * 28 * -10 * -10 * * 2 * 29 * -10 * -10 * * 2 * 30 * -10 * -10 * * 2 * 31 * -10 * -10 * * 2 * 32 * -10 * -10 * * 2 * 33 * -10 * -10 * * 2 * 34 * -10 * -10 * * 2 * 35 * -10 * -10 * * 2 * 36 * -10 * -10 * * 2 * 37 * -10 * -10 * * 2 * 38 * -10 * -10 * * 2 * 39 * -10 * -10 * * 2 * 40 * -10 * -10 * * 2 * 41 * -10 * -10 * * 2 * 42 * -10 * 623 * * 2 * 43 * -10 * 287 * * 2 * 44 * -10 * -10 * * 2 * 45 * -10 * -10 * * 2 * 46 * -10 * -10 * * 2 * 47 * -10 * -10 * ***********************************************
Type <CR> to continue or q to quit ==>
tree->Scan("pe:re", "pe>0&& re>0", "", 1000, 1);
*********************************************** * Row * Instance * pe * re * *********************************************** * 54 * 1 * 1139 * 876 * * 124 * 15 * 914 * 156 * * 198 * 22 * 1057 * 794 * * 305 * 35 * 1031 * 106 * * 313 * 12 * 946 * 710 * * 395 * 35 * 377 * 157 * * 805 * 41 * 886 * 822 * * 812 * 20 * 1066 * 79 * * 838 * 40 * 1392 * 1307 * * 958 * 22 * 1415 * 1350 * *********************************************** ==> 10 selected entries
tree->Scan("pe:re", "" ,"" ,1 , 54);
*********************************************** * Row * Instance * pe * re * *********************************************** * 54 * 0 * -10 * 212 * * 54 * 1 * 1139 * 876 * * 54 * 2 * -10 * -10 * * 54 * 3 * -10 * -10 * * 54 * 4 * -10 * -10 * * 54 * 5 * -10 * -10 * * 54 * 6 * -10 * -10 * * 54 * 7 * -10 * -10 * * 54 * 8 * -10 * -10 * * 54 * 9 * -10 * -10 * * 54 * 10 * -10 * -10 * * 54 * 11 * -10 * -10 * * 54 * 12 * -10 * -10 * * 54 * 13 * -10 * -10 * * 54 * 14 * -10 * -10 * * 54 * 15 * -10 * -10 * * 54 * 16 * -10 * -10 * * 54 * 17 * -10 * -10 * * 54 * 18 * -10 * -10 * * 54 * 19 * -10 * -10 * * 54 * 20 * -10 * -10 * * 54 * 21 * -10 * -10 * * 54 * 22 * -10 * -10 * * 54 * 23 * -10 * -10 * * 54 * 24 * -10 * -10 * * 54 * 25 * -10 * -10 * * 54 * 26 * -10 * -10 * * 54 * 27 * -10 * -10 * * 54 * 28 * -10 * -10 * * 54 * 29 * -10 * -10 * * 54 * 30 * -10 * -10 * * 54 * 31 * -10 * -10 * * 54 * 32 * -10 * -10 * * 54 * 33 * -10 * -10 * * 54 * 34 * -10 * -10 * * 54 * 35 * -10 * -10 * * 54 * 36 * -10 * -10 * * 54 * 37 * -10 * -10 * * 54 * 38 * -10 * -10 * * 54 * 39 * -10 * -10 * * 54 * 40 * -10 * -10 * * 54 * 41 * -10 * -10 * * 54 * 42 * -10 * -10 * * 54 * 43 * -10 * -10 * * 54 * 44 * -10 * -10 * * 54 * 45 * -10 * -10 * * 54 * 46 * -10 * -10 * * 54 * 47 * -10 * -10 * ***********************************************
Type <CR> to continue or q to quit ==>
f->Close();
Flattening data structure-把数据结构拉平
以事件pie: (8,978)，ring: (42,623),(43,287) 为例
pie和ring的有效信号总数分别为1和2 ，记为 phit=1，rhit=2。
事件信息用多个可变长数组表达：
Int_t phit;
Int_t pid[phit];//pie_id
Int_t per[phit];//pie_energy
Int_t rhit;
Int_t rid[rhit];//ring_id
Int_t rer[rhit];//ring_energy
pid[0] = 8;
per[0] = 978;
rid[0] = 42;
rer[0] = 623;
rid[1] = 43;
rer[1] = 287;
如果有多个同类型探测器：
Int_t xe[3][128], ye[3][128];//raw
Double_t xec[3][128], yec[3][128]; //calibrated
Int_t xhit;
Int_t xdet[xhit]; //dssd:1-3
Int_t xid[xhit];//1-128
Double_t xe[xhit],xec[xhit];
Int_t yhit;
Int_t ydet[yhit]; //dssd:1-3
Int_t yid[yhit];//1-128
Double_t ye[yhit],yec[yhit];
// declaration
Int_t phit;
Int_t pid[1000];
Int_t per[1000];
Int_t rhit;
Int_t rid[1000];
Int_t rer[1000];
TFile *fout=new TFile("s4hit.root", "recreate");
TTree *tree=new TTree("tree", "dssd-hit");
// fixed-length array
tree->Branch("pe", &pe, "pe[48]/I");
tree->Branch("re", &re, "re[48]/I");
// variable length array
//size of array : phit
tree->Branch("phit",&phit,"phit/I");
//array: pid, per
tree->Branch("pid",&pid,"pid[phit]/I");
tree->Branch("per",&pee,"per[phit]/I");
//size of array : rhit
tree->Branch("rhit",&rhit,"rhit/I");
//array: pid, per
tree->Branch("rid",&rid,"rid[rhit]/I");
tree->Branch("rer",&rer,"rer[rhit]/I");
// tree event loop
//... ... ...
for(Long64_t jentry=0; jentry<nentries; jentry++) {
tree->GetEntry(jentry);
//x-side
phit = 0;
for(int i=0; i<48; i++) {
if(pe[i]>0) {//有效信号的能量阈值
pid[phit] = i;
per[phit] = pe[i];
phit++;
}
}
rhit = 0;
for(int i=0; i<48; i++) {
if(re[i] > 0) {//有效信号的能量阈值
pid[rhit] = i;
per[rhit] = pe[i];
rhit++;
}
}
if(rhit>0 || phit>0) tree->Fill();
if(jentry % 20000 == 0)
cout << jentry << endl;
}
tree->Write();
fout->Close();
}
//%jsroot on
TFile *fhit=new TFile("s4hit.root");
TTree *tr=(TTree*) fhit->Get("tree");
tr->Print();//ree，pee为刻度后数据。
****************************************************************************** *Tree :tree : alpha * *Entries : 5790825 : Total = 2541888463 bytes File Size = 188942263 * * : : Tree compression factor = 13.46 * ****************************************************************************** *Br 0 :pe : pe[48]/I * *Entries : 5790825 : Total Size= 1112292512 bytes File Size = 29248218 * *Baskets : 5099 : Basket Size= 25600000 bytes Compression= 38.03 * *............................................................................* *Br 1 :re : re[48]/I * *Entries : 5790825 : Total Size= 1112292512 bytes File Size = 41772927 * *Baskets : 5099 : Basket Size= 25600000 bytes Compression= 26.62 * *............................................................................* *Br 2 :rhit : rhit/I * *Entries : 5790825 : Total Size= 23179708 bytes File Size = 2833849 * *Baskets : 177 : Basket Size= 291840 bytes Compression= 8.18 * *............................................................................* *Br 3 :rid : rid[rhit]/I * *Entries : 5790825 : Total Size= 52791843 bytes File Size = 14089701 * *Baskets : 357 : Basket Size= 7382528 bytes Compression= 3.75 * *............................................................................* *Br 4 :ree : ree[rhit]/F * *Entries : 5790825 : Total Size= 52791850 bytes File Size = 34140607 * *Baskets : 357 : Basket Size= 7382528 bytes Compression= 1.55 * *............................................................................* *Br 5 :rer : rer[rhit]/I * *Entries : 5790825 : Total Size= 52791843 bytes File Size = 22519855 * *Baskets : 357 : Basket Size= 7382528 bytes Compression= 2.34 * *............................................................................* *Br 6 :phit : phit/I * *Entries : 5790825 : Total Size= 23179708 bytes File Size = 2488050 * *Baskets : 177 : Basket Size= 291840 bytes Compression= 9.31 * *............................................................................* *Br 7 :pid : pid[phit]/I * *Entries : 5790825 : Total Size= 37522837 bytes File Size = 10440561 * *Baskets : 288 : Basket Size= 7190016 bytes Compression= 3.59 * *............................................................................* *Br 8 :pee : pee[phit]/F * *Entries : 5790825 : Total Size= 37522844 bytes File Size = 18283102 * *Baskets : 288 : Basket Size= 7190016 bytes Compression= 2.05 * *............................................................................* *Br 9 :per : per[phit]/I * *Entries : 5790825 : Total Size= 37522837 bytes File Size = 13024115 * *Baskets : 288 : Basket Size= 7190016 bytes Compression= 2.88 * *............................................................................*
tr->Scan("phit:pid:per:rhit:rid:rer","","",10,1);
*********************************************************************************************** * Row * Instance * phit * pid * per * rhit * rid * rer * *********************************************************************************************** * 1 * 0 * 1 * 10 * 983 * 0 * * * * 2 * 0 * 1 * 8 * 978 * 2 * 42 * 623 * * 2 * 1 * 1 * * * 2 * 43 * 287 * * 3 * 0 * 1 * 27 * 928 * 2 * 4 * 740 * * 3 * 1 * 1 * * * 2 * 5 * 169 * * 4 * 0 * 0 * * * 2 * 1 * 670 * * 4 * 1 * 0 * * * 2 * 2 * 379 * * 5 * 0 * 1 * 44 * 1402 * 0 * * * * 6 * 0 * 0 * * * 2 * 27 * 58 * * 6 * 1 * 0 * * * 2 * 28 * 854 * * 7 * 0 * 0 * * * 2 * 20 * 240 * * 7 * 1 * 0 * * * 2 * 21 * 807 * * 8 * 0 * 0 * * * 2 * 45 * 1236 * * 8 * 1 * 0 * * * 2 * 46 * 183 * * 9 * 0 * 0 * * * 1 * 11 * 52 * * 10 * 0 * 0 * * * 2 * 35 * 811 * * 10 * 1 * 0 * * * 2 * 36 * 624 * ***********************************************************************************************
tr->Draw("rhit");
c1->Draw();
tr->Draw("rer>>(1600,0,1600)","rhit==0");
c1->Draw();
tr->Draw("phit");
c1->Draw();
tr->Scan("pid:per:rid:rer:phit:rhit","","",10,1);
*********************************************************************************************** * Row * Instance * pid * per * rid * rer * phit * rhit * *********************************************************************************************** * 1 * 0 * 10 * 983 * * * 1 * 0 * * 2 * 0 * 8 * 978 * 42 * 623 * 1 * 2 * * 2 * 1 * * * 43 * 287 * 1 * 2 * * 3 * 0 * 27 * 928 * 4 * 740 * 1 * 2 * * 3 * 1 * * * 5 * 169 * 1 * 2 * * 4 * 0 * * * 1 * 670 * 0 * 2 * * 4 * 1 * * * 2 * 379 * 0 * 2 * * 5 * 0 * 44 * 1402 * * * 1 * 0 * * 6 * 0 * * * 27 * 58 * 0 * 2 * * 6 * 1 * * * 28 * 854 * 0 * 2 * * 7 * 0 * * * 20 * 240 * 0 * 2 * * 7 * 1 * * * 21 * 807 * 0 * 2 * * 8 * 0 * * * 45 * 1236 * 0 * 2 * * 8 * 1 * * * 46 * 183 * 0 * 2 * * 9 * 0 * * * 11 * 52 * 0 * 1 * * 10 * 0 * * * 35 * 811 * 0 * 2 * * 10 * 1 * * * 36 * 624 * 0 * 2 * ***********************************************************************************************
tr->Draw("rid[0]:rid[1]>>(48,0,48,48,0,48)","rhit==2","colz");
gPad->SetLogz();
c1->Draw();
tr->Draw("rer[0]:rer[1]>>(400,0,1600,400,0,1600)","abs(rid[0]-rid[1])==1","colz");
c1->Draw();
tr->Draw("rer[0]:rer[1]>>(400,0,1600,400,0,1600)","abs(rid[0]-rid[1])!=1","colz");
c1->Draw();
tr->Draw("per[0]:rer[0]>>(400,0,1600,400,0,1600)","","colz");//per[0]:rer[1]
c1->Draw();
tr->Draw("per:rer>>(400,0,1600,400,0,1600)","pid[0]==10 && rid[0]==30","colz");
gPad->SetLogz();
c1->Draw();
tr->Draw("rer[0]:rer[1]>>(400,0,1600,400,0,1600)","rid[0]==13&&rid[1]==14","colz");
gPad->SetLogz();
c1->Draw();
tr->Draw("per:pid>>(48,0,48,800,0,1600)","","colz");
c1->Draw();
tr->Draw("rer:rid>>(48,0,48,800,0,1600)","","colz");
c1->Draw();
tr->Draw("pee:pid>>(48,0,48,800,0,10000)","","colz");
c1->Draw();
tr->Draw("ree:rid>>(48,0,48,800,0,10000)","","colz");
c1->Draw();
