Logo ROOT   6.18/05
Reference Guide
treeClient.C
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1/// \file
2/// \ingroup tutorial_net
3/// Client program which creates and fills 2 histograms and a TTree.
4/// Every 1000000 fills the histograms and TTree is send to the server which displays the histogram.
5///
6/// To run this demo do the following:
7/// - Open at least 2 windows
8/// - Start ROOT in the first windows
9/// - Execute in the first window: .x fastMergeServer.C
10/// - Execute in the other windows: root.exe -b -l -q .x treeClient.C
11/// (You can put it in the background if wanted).
12/// If you want to run the hserv.C on a different host, just change
13/// "localhost" in the TSocket ctor below to the desired hostname.
14///
15/// \macro_code
16///
17/// \authors Fons Rademakers, Philippe Canal
18
19#include "TMessage.h"
20#include "TBenchmark.h"
21#include "TSocket.h"
22#include "TH2.h"
23#include "TTree.h"
24#include "TMemFile.h"
25#include "TRandom.h"
26#include "TError.h"
27
28void treeClient(Bool_t evol=kFALSE)
29{
30 gBenchmark->Start("treeClient");
31
32 // Open connection to server
33 TSocket *sock = new TSocket("localhost", 9090);
34 if (!sock->IsValid()) {
35 Error("treeClient","Could not establish a connection with the server %s:%d.","localhost",9090);
36 return;
37 }
38
39 // Wait till we get the start message
40 // server tells us who we are
41 Int_t status, version, kind;
42 sock->Recv(status, kind);
43 if (kind != 0 /* kStartConnection */)
44 {
45 Error("treeClient","Unexpected server message: kind=%d status=%d\n",kind,status);
46 delete sock;
47 return;
48 }
49 sock->Recv(version, kind);
50 if (kind != 1 /* kStartConnection */)
51 {
52 Fatal("treeClient","Unexpected server message: kind=%d status=%d\n",kind,status);
53 } else {
54 Info("treeClient","Connected to fastMergeServer version %d\n",version);
55 }
56
57 int idx = status;
58
59 Float_t messlen = 0;
60 Float_t cmesslen = 0;
61
62 TMemFile *file = new TMemFile("mergedClient.root","RECREATE");
63 TH1 *hpx;
64 if (idx == 0) {
65 // Create the histogram
66 hpx = new TH1F("hpx","This is the px distribution",100,-4,4);
67 hpx->SetFillColor(48); // set nice fillcolor
68 } else {
69 hpx = new TH2F("hpxpy","py vs px",40,-4,4,40,-4,4);
70 }
71 Float_t px, py;
72 TTree *tree = new TTree("tree","tree");
73 tree->SetAutoFlush(4000000);
74 tree->Branch("px",&px);
75 tree->Branch("py",&py);
76
79
80 // Fill histogram randomly
82 const int kUPDATE = 1000000;
83 for (int i = 0; i < 25000000; ) {
84 gRandom->Rannor(px,py);
85 if (idx%2 == 0)
86 hpx->Fill(px);
87 else
88 hpx->Fill(px,py);
89 tree->Fill();
90 ++i;
91 if (i && (i%kUPDATE) == 0) {
92 file->Write();
93 mess.Reset(kMESS_ANY); // re-use TMessage object
94 mess.WriteInt(idx);
95 mess.WriteTString(file->GetName());
96 mess.WriteLong64(file->GetEND()); // 'mess << file->GetEND();' is broken in CINT for Long64_t
97 file->CopyTo(mess);
98 sock->Send(mess); // send message
99 messlen += mess.Length();
100 cmesslen += mess.CompLength();
101
102 file->ResetAfterMerge(0); // This resets only the TTree objects.
103 hpx->Reset();
104 }
105 }
106 sock->Send("Finished"); // tell server we are finished
107
108 if (cmesslen > 0)
109 printf("Average compression ratio: %g\n", messlen/cmesslen);
110
111 gBenchmark->Show("hclient");
112
113 // Close the socket
114 sock->Close();
115}
@ kMESS_ANY
Definition: MessageTypes.h:31
@ kMESS_OBJECT
Definition: MessageTypes.h:35
int Int_t
Definition: RtypesCore.h:41
const Bool_t kFALSE
Definition: RtypesCore.h:88
bool Bool_t
Definition: RtypesCore.h:59
float Float_t
Definition: RtypesCore.h:53
R__EXTERN TBenchmark * gBenchmark
Definition: TBenchmark.h:59
void Info(const char *location, const char *msgfmt,...)
void Error(const char *location, const char *msgfmt,...)
void Fatal(const char *location, const char *msgfmt,...)
R__EXTERN TRandom * gRandom
Definition: TRandom.h:62
virtual void SetFillColor(Color_t fcolor)
Set the fill area color.
Definition: TAttFill.h:37
virtual void Start(const char *name)
Starts Benchmark with the specified name.
Definition: TBenchmark.cxx:174
virtual void Show(const char *name)
Stops Benchmark name and Prints results.
Definition: TBenchmark.cxx:157
1-D histogram with a float per channel (see TH1 documentation)}
Definition: TH1.h:571
The TH1 histogram class.
Definition: TH1.h:56
virtual void Reset(Option_t *option="")
Reset this histogram: contents, errors, etc.
Definition: TH1.cxx:6700
virtual Int_t Fill(Double_t x)
Increment bin with abscissa X by 1.
Definition: TH1.cxx:3258
2-D histogram with a float per channel (see TH1 documentation)}
Definition: TH2.h:248
A TMemFile is like a normal TFile except that it reads and writes only from memory.
Definition: TMemFile.h:19
static void EnableSchemaEvolutionForAll(Bool_t enable=kTRUE)
Static function enabling or disabling the automatic schema evolution.
Definition: TMessage.cxx:116
virtual void SetSeed(ULong_t seed=0)
Set the random generator seed.
Definition: TRandom.cxx:597
virtual void Rannor(Float_t &a, Float_t &b)
Return 2 numbers distributed following a gaussian with mean=0 and sigma=1.
Definition: TRandom.cxx:489
virtual Int_t Recv(TMessage *&mess)
Receive a TMessage object.
Definition: TSocket.cxx:816
virtual void Close(Option_t *opt="")
Close the socket.
Definition: TSocket.cxx:388
virtual Bool_t IsValid() const
Definition: TSocket.h:132
virtual Int_t Send(const TMessage &mess)
Send a TMessage object.
Definition: TSocket.cxx:521
A TTree represents a columnar dataset.
Definition: TTree.h:71
Definition: file.py:1
Definition: tree.py:1