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#include <stdio.h>
#include <iostream>
#include <vector>
#include <chrono>
#include "TFile.h"
#include "TTree.h"
#include "TBranch.h"
#include "TInterpreter.h"
void read_jagged0_root() {
float data;
data = 3.14;
TFile* f = new TFile("/home/jpivarski/storage/data/chep-2021-jagged-jagged-jagged/zlib9-jagged0.root");
TTree* t;
f->GetObject("tree", t);
TBranch* b;
b = nullptr;
t->SetBranchAddress("branch", &data, &b);
auto begin_time = std::chrono::high_resolution_clock::now();
int64_t num_entries = b->GetEntries();
int64_t num_baskets = b->GetWriteBasket();
Long64_t* basket_starts = b->GetBasketEntry();
for (int64_t basketid = 0; basketid < num_baskets; basketid++) {
int64_t start = basket_starts[basketid];
int64_t stop = num_entries;
if (basketid + 1 < num_baskets) {
stop = basket_starts[basketid + 1];
}
std::vector<float> content;
content.reserve(1024);
for (int64_t i = start; i < stop; i++) {
b->GetEntry(i);
content.push_back(data);
}
}
auto end_time = std::chrono::high_resolution_clock::now();
int64_t count_nanoseconds = std::chrono::duration_cast<std::chrono::nanoseconds>(
end_time - begin_time
).count();
std::cout << "ROOT zlib9-jagged0.root " << num_entries << " entries " << (count_nanoseconds / 1e9) << " seconds" << std::endl;
}
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