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// 0.403273203 sec | |
package main | |
import "fmt" | |
import "time" | |
func main() { | |
start := time.Now().UnixNano() | |
for i := 0; i < 1000000000; i++ { | |
} | |
finish := time.Now().UnixNano() | |
dur := float64(finish-start) | |
fmt.Println(dur / 1000000000) | |
} |
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# 41.40947604179382 sec | |
import time | |
start = time.time() | |
for i in range(1000000000): | |
pass | |
finish = time.time() | |
print(finish-start) |
А вообще, эквивалентный код на питоне будет таким:
import time
start = time.time()
i = 0
while i < 1000000000:
++i
finish = time.time()
print(finish-start)
У вас питон-то хоть третьей версии? :-)
Я тут запилил эквивалент на D - в дебажном режиме в 4 раза медленнее Go, в релизе - в 2 раза быстрее.
package main
import "fmt"
import "time"
func main()
{
start := time.Now().UnixNano()
accum := 0
for i := 0; i < 1000000000; i++ {
accum += i
}
finish := time.Now().UnixNano()
dur := float64(finish-start)
fmt.Println(dur / 1000000000)
}
import std.stdio;
import std.datetime;
void main()
{
StopWatch timer;
timer.start();
int accum = 0;
for( int i = 0 ; i < 1000000000 ; i++ ) {
accum += i;
}
writeln( timer.peek().msecs / 1000.0 );
}
> go run test.go
0.5103397
> dub
2.136
> dub --build=release
0.297
Добавлю свои 5 копеек по питончику. Я, правда, не понял то ли у вас тут выше код суммирует числа от 1 до миллиарда, то ли суммирует миллиард единичек. Но я и такой и такой тест сделал.
import sys
import timeit
import itertools
executions = 10
def sum_of_one():
return sum(itertools.repeat(1, 1000000000))
def accum():
return sum(range(1000000000))
sum_of_one_time = timeit.timeit(sum_of_one, number=executions)
accum_time = timeit.timeit(accum, number=executions)
print(sys.version)
print('Executed %s times' % executions)
print('Sum of 1', sum_of_one_time, sum_of_one_time/executions)
print('Accumulate from 1 to 1000000000', accum_time, accum_time/executions)
Результаты:
Python 3.5.0:
3.5.0 (default, Oct 15 2015, 12:52:25)
[GCC 4.2.1 Compatible Apple LLVM 7.0.0 (clang-700.0.72)]
Executed 10 times
Sum of 1 96.66175519199987 9.666175519199987
Accumulate from 1 to 1000000000 249.16431563599963 24.916431563599964
PyPy
2.7.10 (f3ad1e1e1d62, Aug 28 2015, 09:36:42)
[PyPy 2.6.1 with GCC 4.2.1 Compatible Apple LLVM 5.1 (clang-503.0.40)]
Executed 10 times
('Sum of 1', 12.96062684059143, 1.2960626840591432)
('Accumulate from 1 to 1000000000', 12.47924280166626, 1.247924280166626)
PyPy3
3.2.5 (b2091e973da6, Oct 19 2014, 18:30:58)
[PyPy 2.4.0 with GCC 4.2.1 Compatible Apple LLVM 6.0 (clang-600.0.51)]
Executed 10 times
Sum of 1 12.533483028411865 1.2533483028411865
Accumulate from 1 to 1000000000 12.479850053787231 1.2479850053787231
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хотя при текущем уровне развития процессоров такой простой цикл может выкинуть процессор при трансляции в микрокод. поэтому пустые циклы не рекомендуется использовать для сравнения производительности.