由买买提看人间百态

topics

全部话题 - 话题: elapses
首页 上页 1 2 3 4 5 6 7 8 9 (共9页)
h*********e
发帖数: 247
1
我刚试了一个<>的例子,
svn co http://svn.springbyexample.org/enterprise/simple-spring-jms/tags/1.0.1/ simple-spring-jms
惊讶的发现logger.info print 出来的 date time 竟然比实际时间(Wed Dec 28 18:50
:02 EST 2011) 提前5个小时: Dec 28 2011 23:49:58!!!
Dec 28 2011 23:49:58 INFO org.springbyexample.jms.JmsMessageListener -
Processe

[INFO] Finished at: Wed Dec 28 18:50:02 EST 2011
哪位知道这是咋回事,也许哪儿有locale设置成比如德国, 我试着search “de" in
eclipse, 但没找到。
请参看下边输出,
....\SpringByExample\simple-spring-jms>mvn clean install
De... 阅读全帖
a*****s
发帖数: 2663
2
来自主题: Linux版 - 关于samba/cifs的速度
network itself seems to be ok, 685.56Mb/sec, however it eats up 52.45% the 1.6GHz CPU!
$ /opt/csw/bin/netperf -H ubuntu.local -t TCP_STREAM -c -C -- -S 1048576
TCP STREAM TEST from ::ffff:0.0.0.0 (0.0.0.0) port 0 AF_INET to ::ffff:192.
168.0.124 (192.168.0.124) port 0 AF_INET
Recv Send Send Utilization Service
Demand
Socket Socket Message Elapsed Send Recv Send Recv
Size Size Size Time Throughput local remote loc
y**b
发帖数: 10166
3
请问一般用什么通用的方法和工具?
有几个问题请教:
(1)PAPI_MEM_SCY(Cycles Stalled Waiting for Memory Access,好处是可以嵌在代
码里面,尤其适合并行计算)似乎不支持sandybridge/ivybridge/haswell几种处理器,
是不是意味着基于PAPI的TAU,PerfSuite,HPCToolkit也没法做这种测试?
(2)用perf进行了测试,结果如下
perf stat -p 48382 sleep 10
Performance counter stats for process id '48382':
4821.604141 task-clock (msec) # 0.963 CPUs utilized
[100.00%]
1,218 context-switches # 0.253 K/sec
[100.00%]
0 ... 阅读全帖
y****i
发帖数: 156
4
来自主题: Programming版 - Clock() problem
// from MSDN
clock():
The returned value is the product of the amount of time that has elapsed since
the start of a process and the value of the CLOCKS_PER_SEC constant.
CLOCKS_PER_SEC = 1000
the_elapse_time(sec) < 1 sec since your comuter is very fast => the_elapse_
time = 0
=> your result = 0
w***n
发帖数: 1137
5
来自主题: Programming版 - 问一个c的问题
got it, googled this
EXAMPLES
Getting the Current Time
The following example uses the time() function to calculate the time elapsed
, in seconds, since the Epoch, localtime() to convert that value to a broken
-down time, and asctime() to convert the broken-down time values into a
printable string.
#include
#include
int main(void)
{
time_t result;
result = time(NULL);
printf("%s%ju secs since the Epoch\n",
asctime(localtime(&result)),
(uintmax_t)resu
d*******o
发帖数: 5897
6
Hi, I have a C program like this:
...
CODE_BLOCK;
...
I want to know how much CPU time spent on CODE_BLOCK. Since the process
executing CODE_BLOCK may be preempted during execution, this CPU time may
not be equal to the (wall-clock) time elapsed from the beginning of CODE_
BLOCK to the end of it.
Can anyone tell me how to do this?
Thanks.
c****r
发帖数: 576
7
来自主题: Programming版 - 震惊:java 的矩阵操作比 c++ 快?
Matlab矩阵计算也就零点几秒,不用循环。
tic;
s = m * repmat((0:1999)',1,2000);
allsum = sum(s(:)) + sum(0:1999);
toc
Elapsed time is 0.478149 seconds
p**o
发帖数: 3409
8
来自主题: Programming版 - Python做计算怎么只用一个核?
python3的concurrent.futures有一些便利,可以在一个with语句块里多进程。
python2可以自己摸索一下multiprocessing
偷懒的话可以参考我下面的代码(从我自己写函数库里扒出来的),
实现的是一个比较通用的进程池链(把几个进程池串联起来)。
后面附一个使用示例。
要睡觉没时间慢慢解释了,看得懂就用,看不懂就算了...
文件 parallel.py
# -*- coding: utf-8 -*-
#
#
""" Helper functions and templates for multiprocessing.
http://docs.python.org/2/library/multiprocessing.html#examples
http://hg.python.org/cpython/file/3.3/Lib/concurrent/futures/pr
http://www.ibm.com/developerworks/aix/library/au-threadingpytho
"""
__all__ = [
'ProcessPo... 阅读全帖
j******a
发帖数: 100
9
来自主题: Programming版 - 服务器测试结果
中午休息的时候,我跑了一下
两台HSX EP的DP
一台2颗CPU是 E5-2699 v3
另一台两颗CPU是 E5-2695 v3
都是8根16G的DDR4 跑1866
10G是X540对联,10G都在头一个CPU上
(client)10.10.172.1《-》10.10.172.2(server)
net/TCP参数我看了下,改了下MTU,其他的没动
netperf -t TCP_STREAM -H 10.10.172.2 -l 10
MIGRATED TCP STREAM TEST from 0.0.0.0 (0.0.0.0) port 0 AF_INET to 10.10.172.
2 () port 0 AF_INET : demo
Recv Send Send
Socket Socket Message Elapsed
Size Size Size Time Throughput
bytes bytes bytes secs. 10^6bits/sec
87380 16384 16384 10.00 ... 阅读全帖
y**b
发帖数: 10166
10
perf不错,好像不能测试mpi程序。请看这个例子:
perf stat -p 48382 sleep 10
Performance counter stats for process id '48382':
4821.604141 task-clock (msec) # 0.963 CPUs utilized
[100.00%]
1,218 context-switches # 0.253 K/sec
[100.00%]
0 cpu-migrations # 0.000 K/sec
[100.00%]
0 page-faults # 0.000 K/sec
17,312,623,873 cycles ... 阅读全帖
y***r
发帖数: 65
11
来自主题: Unix版 - [转载] Help, about clock().
【 以下文字转载自 Programming 讨论区,原文如下 】
发信人: ycbcr (psb), 信区: Programming
标 题: Help, about clock().
发信站: The unknown SPACE (Tue Nov 21 17:34:02 2000) WWW-POST
To monitor program executing time, I used clock() in the
following C program:
{
clock_t start_time, end_time;
start_time = clock();
/* body of program */
end_time = clock();
printf("Elapsed time: %f\n", (end_time - start_time) );
return 0;
}
When run under UNIX, the difference is always 0. And the
start_time and end_time are al
c********e
发帖数: 417
12
来自主题: Unix版 - What is a jiffy in linux?
As I read it, jiffies are the number of elapsed ticks starting from
the system start. It's increment by 1 for every timer interrupt.
So that depends on how linux programs the programmable timer.
Normally, it's 10ms per tick.
A*****o
发帖数: 222
13
来自主题: Unix版 - what do these numbers mean?
user system elapsed %CPU
this is the output from time commmand
try
man time
h*********s
发帖数: 14
14
来自主题: Unix版 - Question for time command
I am using "time" command to check the running time for my C program. I got
the following info:
3186.71s real 3183.12s user 0.79s system
I checked the manual page for time command but still a little bit confused
about what real, user and system mean. My impression is real actually is the
total elapsed time and real roughly equal to user + system? Am I right?
Any comments are highly appreciated!
g*********d
发帖数: 233
15
Genetic history of an archaic hominin group from Denisova Cave in
Siberia
David Reich, Richard E. Green, Martin Kircher, Johannes Krause,
Nick Patterson, Eric Y. Durand, Bence Viola, Adrian W. Briggs, Udo
Stenzel, Philip L. F. Johnson, Tomislav Maricic, Jeffrey M. Good,
Tomas Marques-Bonet, Can Alkan, Qiaomei Fu, Swapan Mallick, Heng
Li, Matthias Meyer, Evan E. Eichler, Mark Stoneking, Michael
Richards, Sahra Talamo, Michael V. Shunkov, Anatoli P. Derevi... 阅读全帖
t*d
发帖数: 1290
16
来自主题: Biology版 - Re: 时间是绝对的吗? (转载)
【 以下文字转载自 History 讨论区 】
发信人: sgld (sgld), 信区: History
标 题: Re: 时间是绝对的吗?
发信站: BBS 未名空间站 (Sat Sep 3 17:51:42 2011, 美东)
转一篇文章。
Ten Things Everyone Should Know About Time
by Sean
“Time” is the most used noun in the English language, yet it remains a
mystery. We’ve just completed an amazingly intense and rewarding
multidisciplinary conference on the nature of time, and my brain is swimming
with ideas and new questions. Rather than trying a summary (the talks will
be online soon), here’s my stab at ... 阅读全帖
l**********1
发帖数: 5204
17
sure
add one recent paper
Levy S at al. (2011)
The competitive advantage of a dual-transporter system.
Science. 334: 1408-12.
Abstract
Cells use transporters of different affinities to regulate nutrient influx.
When nutrients are depleted, low-affinity transporters are replaced by high-
affinity ones. High-affinity transporters are helpful when concentrations of
nutrients are low, but the advantage of reducing their abundance when
nutrients are abundant is less clear. When we eliminated such red... 阅读全帖
n*********m
发帖数: 38
18
来自主题: Biology版 - 做生物的悲剧
Doubts about Johns Hopkins research have gone unanswered, scientist says
By Peter Whoriskey, Published: March 11
The numbers didn’t add up.
Over and over, Daniel Yuan, a medical doctor and statistician, couldn’t
understand the results coming out of the lab, a prestigious facility at
Johns Hopkins Medical School funded by millions from the National Institutes
of Health.
He raised questions with the lab’s director. He reran the calculations on
his own. He looked askance at the articles arising fro... 阅读全帖
d*****s
发帖数: 647
19
Nature. 2013 Nov 7;503(7474):146. doi: 10.1038/nature12727.
Retraction: Functional dissection of lysine deacetylases reveals that HDAC1
and p300 regulate AMPK.
Yu-yi Lin, Samara Kiihl, Yasir Suhail, Shang-Yun Liu, Yi-hsuan Chou, Zheng
Kuang, Jin-ying Lu, Chin Ni Khor, Chi-Long Lin, Joel S. Bader, Rafael
Irizarry & Jef D. Boeke
Nature 482, 251'255 (2012); doi:10.1038/nature10804
In response to a concern raised by a reader about inconsistencies in our
Letter between the results from the primary mi... 阅读全帖
C****n
发帖数: 79
20
最近在用DAPI染丝状真菌的细胞核,步骤完全是照着教科书或者paper做的。突然发现
DAPI可能会导致细胞核破裂,造成了严重的fake结果。
比如without DAPI staining, 用显微镜观察NLS-GFP是细胞核定位的;但是在DAPI染色
(10min)后观察,GFP的定位变成 cytoplasmic了。然后我做了一个time elapse的实
验,很诡异的发现在某一个时间点细胞核突然间破裂了,定位在细胞核里的GFP突然
distribute to the entire hyphae。
请教各位大虾这是因为DAPI的毒性照成的吗?因为sample比较多,实在不想fix以后再
immunostaining 观察,除此之外有什么好方法吗?十分感谢!
c**m
发帖数: 757
21
先是小蜜发了封
POLY wants you to come back!
然后各大佬们纷纷表示抵制
比如
It is downright irritating to receive this mail knowing very well that at no
time has my membership elapsed. It makes me want to go ahead and cancel it
from now onwards.
Dotsevi Y Sogah
Professor, Department of Chemistry & Chemical Biology Baker Laboratory,
Cornell University, Ithaca New York 14853-1301
还有
Your terse request is both unprofessional, rude and far too late - damage
done!

Please delete my email address from your mailing list.
... 阅读全帖
G****n
发帖数: 145
22
Papers of Steve Cheung above 100 citations
Fable of the Bees: An Economic Investigation, The[PDF] from tripod.comSNS
Cheung - JL & Econ., 1973 - HeinOnline
THE FABLE OF THE BEES: AN ECONOMIC INVESTIGATION* STEVEN NS CHEUNG
University
of Washington Economists possess their full share of the common ability to
invent and commit
errors. . . . Perhaps their most common error is to believe other economists
. George J. ...
Cited by 260 - Related articles - All 11 versions
The contractual nature of the ... 阅读全帖
b**s
发帖数: 589
23
来自主题: Macromolecules版 - 今天的收获
If you have 5-dimentional (X,Y,Z,Compositional,Time-elapse) capability, you
can do it. Imagine a 3-D color printer using a drug controlled release ink.

factor,






cell,然后在放在scaffold里(当然要我们的heterogenerous的
使
s**********i
发帖数: 3
24
请各位大神拔刀相助,帮我度过考试难关,感激不尽!
1. I've made appointment to see two students, one at noon(12:00) and the
other at 12:15. The duration of the appointments are independent exponential
with mean 15 minutes. I cannot meet with the second student until I'm done
with the first. What is the expected amount of time the 12:15 student spends
at my office? Assume the students arrive at their appointed times.
2. Consider the following game. There are two clocks sounding alarms. Clock
A’s alarm sounds according to
... 阅读全帖
s*********4
发帖数: 1844
25
之前的问题都解决了,谢谢大家的答复。
再问一个问题,因为2008年国内所有护士证都换成新的号码了,在描述老证的状态一栏
,我该怎么填阿?它有active,elapsed etc,可以选。
t**********m
发帖数: 205
26
既然大爆炸理论得到了梵蒂冈的认可,那么我们来分析一下:创造生命的大爆炸理论究
竟是什么东西?
上一篇博客我谈到了广义相对论是什么东西,参见
http://www.galaxyanatomy.com/
'General Relativity is very simple. It is equivalent to one sentence:
There exists one and only one local inertial reference frame at any point of
a spacetime manifold.
This is similar to the situation that
There exists one and only one local tangent plane at any point of a surface.'
上述一句话就是著名的爱因斯坦的引力等效原理。等效原理讲的就是:引力跟其它三种
相互作用力有本质的不同,引力可以通过参考标架的变换来消灭掉!
爱因斯坦是对的。我们的身体每天遭受着引力的相互作用,而且逆来顺受,已经习惯了
。如果你要... 阅读全帖

发帖数: 1
27
我文章评审结束了, 我收到的最后一封信是这样的
Dear,
We have now given the authors of the paper criticized in your Comment
an opportunity to prepare a formal Reply. The authors will be extended
some time to prepare a Reply and additional time may be needed for
evaluation by a referee. It is our practice to give criticized authors
reasonable opportunity to prepare an acceptable Reply to be published
simultaneously with the Comment, and you should consequently expect
some time to elapse while this is carried out.
Your m... 阅读全帖
d*******1
发帖数: 854
28
来自主题: Statistics版 - 怎样用R找出unique的record
实际情况恰恰相反, 我是symbol极多, 但是每个symbol的duplication较少, 最多2,3个
. 请看以下记录(前面两行是读进CSV DATA):
> glist<- read.csv('all_diff_exp_list.csv',header=TRUE)
> nmglist<- glist[glist$SYMBOL !='',]
>
> system.time(
+ songkun<- tapply(nmglist$fold, nmglist$SYMBOL,
+ function(x) x[order(abs(nmglist$fold), decreasing = T)][1])
+ )
user system elapsed
215.44 1.27 218.31
> songkun<- as.matrix(songkun)
> tail(songkun)
[,1]
ZYG11A NA
ZYG11B NA
ZYG11BL NA
ZYX NA
ZZEF1 NA
ZZZ3 NA
d*******1
发帖数: 854
29
来自主题: Statistics版 - 怎样用R找出unique的record
i see. 谢谢了, 改来改去就晕了. 这回work了, 而且很快:
> glist<- read.csv('all_diff_exp_list.csv',header=TRUE)
> nmglist<- glist[glist$SYMBOL !='',]
>
> system.time(
+ songkun<- tapply(nmglist$fold, nmglist$SYMBOL,
+ function(x) x[order(abs(x), decreasing = T)][1])
+ )
user system elapsed
0.63 0.00 0.63
> songkun<- as.matrix(songkun)
> tail(songkun)
[,1]
ZYG11A 1.01860
ZYG11B 1.18808
ZYG11BL -1.16001
ZYX 1.07424
ZZEF1 -1.11228
ZZZ3 1.19661
z**k
发帖数: 378
30
来自主题: Statistics版 - 考大家一个R问题
为什么不可以。。。
> system.time(for (i in 1:1000) x = runif(1000))
user system elapsed
0.17 0.00 0.16
S******y
发帖数: 1123
31
> X <- matrix(rnorm(250000),500,500)
> system.time(
+ s<-mpinv(X)
+ )
user system elapsed
1.17 0.00 1.17
H*H
发帖数: 472
32
来自主题: Statistics版 - R能读多大的数据? 14GB?
刚用15 GB 数据测试了下,10分钟左右就读完了
system.time(dt <- fread(file))
Read 42663888 rows and 71 (of 71) columns from 15.589 GB file in 00:10:15
user system elapsed
608.957 8.732 617.904
l****i
发帖数: 398
33
来自主题: Statistics版 - 请教如何分割较大的data
用data.table下的fread函数。我读过一个5g多的数据,才2:30秒。对data.table的读
取速度比较满意。
system.time(DT <- fread("201403-201406_with_tv_market.csv"))
Read 16221666 rows and 29 (of 29) columns from 5.380 GB file in 00:02:30
user system elapsed
137.17 3.48 149.70
k*******a
发帖数: 772
34
来自主题: Statistics版 - R 两个大矩阵相乘,太慢怎么办呢
多快叫快?
a = matrix(rnorm(2000*2000), nrow=2000)
b = matrix(rnorm(2000*2000), nrow=2000)
system.time(a %*% b)
user system elapsed
4.705 0.004 4.708
如果你的时间远远超过这个,那估计是硬件的问题
o****o
发帖数: 8077
35
来自主题: Statistics版 - R 两个大矩阵相乘,太慢怎么办呢
你的也太慢了,用的default的BLAS吧
> a = matrix(rnorm(2000*2000), nrow=2000)
>
> b = matrix(rnorm(2000*2000), nrow=2000)
>
> system.time(a %*% b)
user system elapsed
1.47 0.04 0.26
o****o
发帖数: 8077
36
来自主题: Statistics版 - R 两个大矩阵相乘,太慢怎么办呢
你的啥机器啊,用的R自带的BLAS吧
我的i5-3570k,没超频
上一个是至强的六核CPU
> a = matrix(rnorm(2000*2000), nrow=2000)
> b = matrix(rnorm(2000*2000), nrow=2000)
> system.time(a %*% b)
user system elapsed
1.42 0.14 0.43
>
l****i
发帖数: 398
37
来自主题: Statistics版 - R 两个大矩阵相乘,太慢怎么办呢
如果嫌麻烦自己装open blas什么的, 可以直接装一个revolution r open. RRO自带
Intel Math Kernel Library (MKL)可以multi-thread矩阵运算。我用的i5-3320m, 16g
内存,只能2个线程,速度也还行。
> if(require(RevoUtilsMath)){
+ setMKLthreads(2)
+ }
Loading required package: RevoUtilsMath
>
> a = matrix(rnorm(2000*2000), nrow=2000)
> b = matrix(rnorm(2000*2000), nrow=2000)
>
> system.time(a %*% b)
user system elapsed
0.92 0.00 0.52
A*******s
发帖数: 9638
38
来自主题: Medicalpractice版 - 中国医生的偶像应该是谁?
中国医生有偶像吗? 我觉得够呛,中医可以有李时珍什么的,中国的西医们不会把希
波克拉底当偶像吧?
最近因为externship的事与韩国人有一些接触,我知道中国人似乎对韩国人对中国古代
文化的说法有非议,但这个韩国医生实在让我另眼相看,他说他从小崇拜孙中山,我的
老中朋友是不信的,觉得是忽悠,但看看他给我的这个文章,他能不崇拜孙中山吗?
这个讲话时是孙中山100年前在日本的一个讲话, 难怪中国有中山医学院,但有几个人
知道孙中山的这个讲话?
Gentlemen: I highly appreciate this cordial reception with which you are
honoring me today. The topic of the day is "Pan-Asianism," but before we
touch upon the subject, we must first have a clear conception of Asia's
place in the world. Asia, in my opinion, is the cradle of t... 阅读全帖
A*******s
发帖数: 9638
39
来自主题: Medicalpractice版 - 中国医生的偶像应该是谁?
中国医生有偶像吗? 我觉得够呛,中医可以有李时珍什么的,中国的西医们不会把希
波克拉底当偶像吧?
最近因为externship的事与韩国人有一些接触,我知道中国人似乎对韩国人对中国古代
文化的说法有非议,但这个韩国医生实在让我另眼相看,他说他从小崇拜孙中山,我的
老中朋友是不信的,觉得是忽悠,但看看他给我的这个文章,他能不崇拜孙中山吗?
这个讲话时是孙中山100年前在日本的一个讲话, 难怪中国有中山医学院,但有几个人
知道孙中山的这个讲话?
Gentlemen: I highly appreciate this cordial reception with which you are
honoring me today. The topic of the day is "Pan-Asianism," but before we
touch upon the subject, we must first have a clear conception of Asia's
place in the world. Asia, in my opinion, is the cradle of t... 阅读全帖
d*****n
发帖数: 1875
40
来自主题: Tri版 - 梦开始的地方
Wednesday night group riding, 算是骑的比较轻松吧。
骑行效率很高,平均 watts 才 147 瓦就能达到比较快的速度。
Summary
Distance: 26.73 mi
Time: 1:12:55
Avg Speed: 22.0 mph
Elevation Gain: 688 ft
Calories: 629 C
Details
Timing
Time: 1:12:55
Moving Time: 1:12:55
Elapsed Time: 1:13:08
Avg Speed: 22.0 mph
Avg Moving Speed: 22.0 mph
Max Speed: 33.6 mph
SpeedPace
Elevation
Elevation Gain: 688 ft
Elevation Loss: 700 ft
MinElevation: 808 ft
... 阅读全帖
w***n
发帖数: 9040
41
2012.08.19 密西根湖里游泳43分钟,1800m
中午做饭不小心把手指给切破了,伤口虽然不大,但是挺深的。
轻伤不下火线,贴了个创可贴还是按计划去湖里游泳,结果穿wet suit,创可贴就掉了。
游完上岸,血就开始哗哗流呀。
开放水域果然不一样呀,今天风大浪大,感觉跟坐电梯似的,上上下下的享受呀。
经常是游得好好的,一个大浪过来就给我打歪了,交替锻炼了4次打腿,和两次打腿。
Activity Type: Open Water Swimming
Distance: 1.14 mi
Time: 43:00
Avg Pace: 37:46 min/mi
Calories: 598 C
Time: 43:00
Moving Time: 42:16
Elapsed Time: 43:00
Avg Pace: 37:46 min/mi
Avg Moving Pace: 37:07 min/mi
Avg Swim Cadence: 23 strokes/min
Max Swim Cadence: 73 strokes/min
w***n
发帖数: 9040
42
来自主题: Tri版 - Aquathlon回来啦
游泳37分钟,Transition 5分钟,5公里24分钟
Swim:
200人同时一起下水,跟下饺子一样,各种踢、打、换气被溅水,我还跟一个人游偏了
很远。
1500m,愣是游出来1658m(GPS显示)
Distance: 1.03 mi
Time: 37:02
Avg Pace: 36:01 min/mi
Elevation Gain: 0 ft
Calories: 561 C
Time: 37:02
Moving Time: 36:03
Elapsed Time: 37:05
Avg Pace: 36:01 min/mi
Avg Swim Cadence: 25 strokes/min
Max Swim Cadence: 40 strokes/min
Transition Time 5:10
Running:GPS显示5.23公里我跑了24分整
Distance: 3.25 mi
Time: 24:00
Avg Pace: 7:23 min/mi
Elevation Gain: 259 f... 阅读全帖
c*****9
发帖数: 32
43
我的比赛报告, 平均心率有点高:168. 最后奔到了188,是因为冲刺了200米。 中间5
-7mile的时候是那个大爬坡, 连走带跑点。 最后一迈抽筋走了会。 大侠请給指点一
下, 下一步在训练上应该如何改进。 多谢!
Split Time Distance Avg Pace
Summary 2:04:12.8 13.23 9:23
1 9:40.3 1.00 9:40
2 9:33.4 1.00 9:34
3 9:10.4 1.00 9:10
4 9:30.2 1.00 9:30
5 9:39.6 1.00 9:40
6 9:36.7 1.00 9:37
7 9:28.7 1.00 9:29
8 9:02.8 1.00 9:03
9 9:30.2 1.00 9:30
10 9:04.9 1.00 9:05
11 9:21.8 ... 阅读全帖
g*r
发帖数: 67
44
来自主题: DataSciences版 - 在R里merge两个dataframe太慢了
R的merge效率太低了。根据一个列合并两个dataframe,长的有1m行,短的1k行:
long =data.frame(a=seq(1,1000000), b=rnorm(10) )
short=data.frame(a=seq(1,2000, 2), c=rnorm(10) )
system.time(merge(x=long, y=short, all.x=T))
user system elapsed
10.286 0.370 10.624
4m行就要将近1分钟。8m行超过2分钟。16m要4分钟。
我的真实数据比例子里的复杂些,且有100m行或更高,卡了半天没动静,只好强行终止
进程。对这个效率有点失望。早听说merge很慢,这次领教了。
如果不依靠外部程序(shell,python之类的script),大家是怎么多快好省做合并的
呢?菜鸟一个,轻拍。
z*******n
发帖数: 1034
45
http://gamerboom.com/archives/83506
发布时间:2014-04-24 11:23:24 Tags:Facebook游戏收益,mark pincus,发现游戏渠道
1)据gamasutra报道,Facebook日前宣布其游戏收益在上个季度仍然强劲,但预计未来
发展将出现困难,因为大量Facebook用户已从桌面平台转向移动平台,而Facebook目前
主要游戏支付收益却是来自桌面平台。
Facebook“整体支付及其他费用”收益是Facebook游戏的主要收益来源,在2014年第一
季度(截止3月31日)达到2.37亿美元,同比去年第一季度增长10%,但其中主要增长却
并非来自游戏业务。
facebook-q12014 payments(from gamasutra)
facebook-q12014 payments(from gamasutra)
Facebook首席财务官David Ebersman表示第一季度Facebook游戏支付收益同比上年仅增
长1%,远低去2013年时Facebook报告所显示的8%年增长率,可见Facebook游戏支付收益... 阅读全帖
p****3
发帖数: 448
46
来自主题: CellularPlan版 - 婷来信催了
什么都不做的话,应该还是安全的我想。
Please act in the next 24 hours
If you haven't already taken action to authenticate with Ting, your previous
RingPlus number is in a holding pattern. 24 hours have elapsed. In another
24 hours, your phone will lose service.
No pressure. OK, fine: Some pressure.
If you want to keep your phone number
Please follow the simple process to authenticate your number. You'll be
invited to try Ting and claim at least $35 in Ting credit. We'd argue you
should totally do that. You don't h... 阅读全帖
L**********y
发帖数: 2525
47
来自主题: _Les_Forum123版 - 需要做些机械的事情
好的,我记着。
谢谢!
(lost track of post #s. about .5hr elapsed)
L**********y
发帖数: 2525
48
来自主题: _Les_Forum123版 - 人生没有后悔药可以吃
我还一直以为双子座的同志长袖善舞,见人说人话,见鬼说鬼话
* 50min elapsed
g****r
发帖数: 306
49
来自主题: _pennystock版 - tomorrow: shippers and coals
pcx looks good
dac,prgn,sblk deserve your attention.
egle ER today and exm tomorrow.
best time for drys and gnk has elapsed
首页 上页 1 2 3 4 5 6 7 8 9 (共9页)