M*******r
发帖数: 165 | 1 给一个seed以后，generator产生的数是uniform distribution.
那么给N个随机的seed（independent，不确定的distribution）到N个generator，产生
的第一个
随机数（N个）也是independent的吗？也是uniform distribution吗？ |
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b*******2
发帖数: 2121 | 2 现在做实验,想要一个high power,high current的pulse generator,具体要求:
square wave,voltage amp: up to 50V
current: up to 2A
pulse width: 100ns~100ms
duty cycle: up to 80%
实验室有一个Agilent | 8114A , 说是duty cycle能到100%,但是duty cycle大于50%以
后,voltage amp就只能到25V了.满足不了要求.
google一下hihg power generator,第一个跳出来就这个. 找不到其他的了,哪位大侠能
够推荐一个,或者推荐下哪里能找到? 多谢啊 |
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b*******2
发帖数: 2121 | 3 请看附图, 是个laser 的 LIV curve,主要看电流和电压,peak 处15V, 70A.
这样的IV curve 需要什么样的pulse generator 能驱动啊? 我只能找到些高电压的
pulse generator, 不知道什么样的能产生这么高电流的呢?
请帮忙推荐一下? 哪里能找到? 或者如果自制,需要怎么样做?
另外, 这个图是从别人paper 中截过来的, 不知道贴在这里合适不? 如果不合适, 请提
醒,我删除掉. 如果原作者也上mit, 看到了请不吝赐教啊. 呵呵~
多谢! |
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n****n
发帖数: 101 | 4 【 以下文字转载自 EE 讨论区 】
发信人: nissan (Go! Millan!), 信区: EE
标 题: 可以用MGF(moment generating function)方法求取非连续变量吗？
发信站: BBS 未名空间站 (Sat Feb 2 01:09:50 2008)
可以用MGF(moment generating function)方法求取非连续变量吗？
MGF思想是，如果{X1, X2,...XN} is a sequence of independent (and not
necessarily identically distributed) random variables, 那么其和M(X)=X1+X2+..
+XN的概率密度函数可以表示为M(X)=M(X1)*M(X2)*...*M(XN)，从而可以通过Xi的密度
函数f(xi)反求其和M(X)的密度函数表达式。
但能够用以上方法求解非连续(non-continuous)的密度函数分布吗？就是说如果Xi是非
连续的离散变量，也可以用此MGF思想吗？
多谢 |
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m******t
发帖数: 273 | 5 【 以下文字转载自 Statistics 讨论区 】
发信人: myregmit (myregmit), 信区: Statistics
标 题: Predict values of vectors by other vectors generated by black box
functions
发信站: BBS 未名空间站 (Sun Mar 2 11:38:56 2014, 美东)
Hi,
I need to solve a problem about predicting values of some numerical vectors
by using other numerical vectors with all these vectors in the same vector
set, which is generated by one or more black box functions.
Given a vector space:
P =[S_1, S_2, …, S_T | Sk is a vector of q numbers, k = 1, ..., T]... 阅读全帖 |
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m******t
发帖数: 273 | 6 【 以下文字转载自 Statistics 讨论区 】
发信人: myregmit (myregmit), 信区: Statistics
标 题: long time generating gamma distribution in python
发信站: BBS 未名空间站 (Thu Mar 13 19:04:24 2014, 美东)
I need to generate a truncated gamma distribution pdf curve and histogram in
python 3.
2 on win7.
import numpy as np
import matplotlib.pyplot as plt
import scipy.special as sps
shape, scale = 2., 2. # mean and dispersion
counter =0
s = []
upper_bound = 4
lower_bound = 0.5
while (counter <= 1000):
t = np.random.gamma(shape, ... 阅读全帖 |
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m******e
发帖数: 45 | 8 How to generate uniform [0,1] distributed random numbers with correlation
rho?
generating correlated gaussian r.vs are trivial, but it seems there is no
clean way
for uniform r.v. , any idea? thanks. |
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m******t
发帖数: 273 | 9 【 以下文字转载自 Statistics 讨论区 】
发信人: myregmit (myregmit), 信区: Statistics
标 题: Predict values of vectors by other vectors generated by black box
functions
发信站: BBS 未名空间站 (Sun Mar 2 11:38:56 2014, 美东)
Hi,
I need to solve a problem about predicting values of some numerical vectors
by using other numerical vectors with all these vectors in the same vector
set, which is generated by one or more black box functions.
Given a vector space:
P =[S_1, S_2, …, S_T | Sk is a vector of q numbers, k = 1, ..., T]... 阅读全帖 |
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m******t
发帖数: 273 | 10 【 以下文字转载自 Statistics 讨论区 】
发信人: myregmit (myregmit), 信区: Statistics
标 题: long time generating gamma distribution in python
发信站: BBS 未名空间站 (Thu Mar 13 19:04:24 2014, 美东)
I need to generate a truncated gamma distribution pdf curve and histogram in
python 3.
2 on win7.
import numpy as np
import matplotlib.pyplot as plt
import scipy.special as sps
shape, scale = 2., 2. # mean and dispersion
counter =0
s = []
upper_bound = 4
lower_bound = 0.5
while (counter <= 1000):
t = np.random.gamma(shape, ... 阅读全帖 |
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m********r
发帖数: 811 | 11 Event generators are software packages that randomly generate particle
physics events produced in particle accelerators, collider experiments, or
during the initial phases of the creation of the Universe (Big Bang). Events
come in different types called 'processes' as discussed in Automatic
calculation of particle interaction or decay. |
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m******t
发帖数: 273 | 12 【 以下文字转载自 Statistics 讨论区 】
发信人: myregmit (myregmit), 信区: Statistics
标 题: Predict values of vectors by other vectors generated by black box
functions
发信站: BBS 未名空间站 (Sun Mar 2 11:38:56 2014, 美东)
Hi,
I need to solve a problem about predicting values of some numerical vectors
by using other numerical vectors with all these vectors in the same vector
set, which is generated by one or more black box functions.
Given a vector space:
P =[S_1, S_2, …, S_T | Sk is a vector of q numbers, k = 1, ..., T]... 阅读全帖 |
|
m******t
发帖数: 273 | 13 【 以下文字转载自 Statistics 讨论区 】
发信人: myregmit (myregmit), 信区: Statistics
标 题: Predict values of vectors by other vectors generated by black box
functions
发信站: BBS 未名空间站 (Sun Mar 2 11:38:56 2014, 美东)
Hi,
I need to solve a problem about predicting values of some numerical vectors
by using other numerical vectors with all these vectors in the same vector
set, which is generated by one or more black box functions.
Given a vector space:
P =[S_1, S_2, …, S_T | Sk is a vector of q numbers, k = 1, ..., T]... 阅读全帖 |
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p********a
发帖数: 5352 | 14 ☆─────────────────────────────────────☆
jejune (孑孓) 于 (Wed Nov 7 12:47:17 2007) 提到:
what is the simplest way to generate 2 uniform random vaiables of given
correlation?
☆─────────────────────────────────────☆
sir ( 郎 ) 于 (Wed Nov 7 18:22:27 2007) 提到:
it is hard to get the simplest one
a simple one is generate independent x and y
and use x, x+ay, where a is a parameter to adjust
☆─────────────────────────────────────☆
jejune (孑孓) 于 (Thu Nov 8 09:49:55 2007) 提到:
but if x,y ~ uni |
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h*****y
发帖数: 2 | 15 As stated in the title, I need to generate the frequencies (probalitiy) for
each category and rank the probality in SAS. If the frequencies are
generated with crosstabluate table, how to rank the numbers? Any one can
help? Thanks! |
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l***o
发帖数: 194 | 16 I am learning from this article about how you can generate a txt file for a
directory. but when I use this one line code here, not working. can anyone
help? I have been trying this for few hours. :-(
thanks.
x “dir c:\chen >c:\chen\proglist.txt”
The generated .TXT file looks like the following:
Volume in drive C has no label
Volume Serial Number is 07CF-0B10
Directory of C:\chen
. 05-24-01 2:35p .
.. 05-24-01 2:35p ..
PROG1 SAS 0 05-24-01 2:35p prog1.sas
PROG2 SAS 0 05-24-01 2:35p pr |
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s********9
发帖数: 74 | 17 I will need to generate the PDF report for a large dataset when dataset
update every time. Most of the SAS output will be acceptable, but the tables
cannot cross the pages. The font sizes will be different for the front page
, contents and section titles. And also the contents should have page number
. Does anyone here know the convenient method to control the SAS output font
size and style? Does anyone here know how to get all those done and
generate the PDF report by SAS code?
If you get any i |
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f***a
发帖数: 329 | 18 From the description of "runif()"
"runif will not generate either of the extreme values unless max = min or
max-min is small compared to min, and in particular not for the default
arguments."
It seems 0 won't be generated, so ceiling(runif(1)*N) should works OK. |
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c***z
发帖数: 6348 | 19 【 以下文字转载自 DataSciences 讨论区 】
发信人: chaoz (晨钟暮鼓), 信区: DataSciences
标 题: generating percentile-percentage charts
发信站: BBS 未名空间站 (Mon Nov 24 20:11:11 2014, 美东)
Spent some time generating this kind of charts from raw data. There might be
better ways of doing so, but I would just post my method and 抛砖引玉。
Raw table has three columns: clinic | age | count, which records the age of
patients, rather, how many of each age category.
Target table has three columns: clinic | age_percentile | count_percentage... 阅读全帖 |
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z*******n
发帖数: 1034 | 20 January 29, 2015 8:08 PM
Jay Yarow
Now that Google has reported earnings, we can add another incredible stat to
Apple’s mind bending fourth quarter performance.
For the December quarter, Apple generated $74.6 billion in sales.
For all of 2014, Google generated $66 billion in sales.
That’s really impressive. So is this…
The combined fourth quarter revenue of Microsoft, Google, and Amazon was $73
.9 billion.
That’s less than Apple did over that same period.
Just as impressive? Apple, against a big... 阅读全帖 |
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w*******y
发帖数: 60932 | 25 Apple iPod touch 8 GB (4th Generation) NEWEST MODEL:
http://www.amazon.com/dp/B001FA1O0O/ref=gs_htljs
Get a $25 Amazon.com Gift Card with This Purchase When you buy this 4th
Generation 8 GB iPod touch, you can get a $25 Gift Card to use at Amazon.com
. Just add BOTH the qualifying iPod touch and the $25 Gift Card to your cart
via the "Add Both to Cart" button located here; you will not be charged for
the Gift Card. Hurry--offer good through 12/18/10 at 11:59 pm Pacific time,
while supplies last
... 阅读全帖 |
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w*******y
发帖数: 60932 | 26 Seventh Generation Dish Liquid, 25-Ounce Bottles (Pack of 6):
http://www.amazon.com/Seventh-Generation-Liquid-25-Ounce-Bottle
List Price: $24.13
Price: $12.57 ($0.08 / oz) & eligible for free shipping with Amazon Prime
You Save: $11.56 (48%)
Save an extra 15% with Subscribe & Save: Sign up to have this item delivered
at a regular interval of your choice, and the current price drops to $10.68
($0.07 / oz)
These are large bottles and usually retail around $4 each.
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w*******y
发帖数: 60932 | 29 Apple iPod shuffle 2 GB Blue (4th Generation) NEWEST MODEL:
http://www.amazon.com/Apple-shuffle-Silver-Generation-NEWEST/dp
Technical Details
Color: Blue
* 2 GB capacity for about 500 songs
* Up to 15 hours of audio playback on a single charge
* Easy-to-use control pad for playing your music, audiobooks, and
podcasts
* Support for AAC, Protected AAC (iTunes Store), MP3, MP3 VBR, Audible,
Apple Lossless, AIFF, and WAV audio formats
* One-year limited warranty
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w*******y
发帖数: 60932 | 30 Although I missed the deal the other day, when I went back to the ATT
wireless site I saw this, they have the iPad 1st Generation 64GB w/3G, new,
for $529.99. Same as the other day where you need to sign up for the data
plan, but can cancel it after the first month.
Here's the link to the item:
Link:
http://www.wireless.att.com/cell-phone-service/cell-phone-detai iPadwith Wi-Fi + 3G 64GB Black&q_sku=sku5110232#fbid=HdKWWOvRnWz
#fbid=HdKWWOvRnWz" rel="nofollow" target="_blank" onclick="_gaq.push... 阅读全帖 |
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w*******y
发帖数: 60932 | 31 Today only Home Depot has the Generac GP5500 generator at an additional $250
off online w/ free shipping. Price comes to $399 + tax.
Link:
http://www.homedepot.com/Featured-Products-May-Savings-Event-To
Pretty good price on a relatively solid emergency generator. $584 looks
like the next cheapest online price.
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w*******y
发帖数: 60932 | 32 Just got an Email from Apple--a big surprise since I haven't purchased any
apple product since 05. It turns out that there might be a defect in the
battery where it could overheat and catch on fire. You can send it in for a
replacement--not sure what kind of Generation you'll get though, but you
might get something better? First gen was 2gb and 4gb. I think the minimum
hdd storage for the current iPod nanos is now is 8gb?
Link is here:
Link:
http://www.apple.com/support/ipodnano_replacement
Atta... 阅读全帖 |
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w*******y
发帖数: 60932 | 33 Flip MinoHD (3rd Generation) - 2 Hour 8gb
Link:
http://www.bestbuy.com/site/Flip Video - MinoHD (3rd Generation) Camcorder - 2 Hour - Black/1325243.p?id=1218250289049&skuId=1325243&st=1325243&cp=1&lp=1
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w*******y
发帖数: 60932 | 35 Seems a good price to me. Not much information online:
homedepot: STGP-3500-Watt Portable Gas Generator $200:
http://www.homedepot.com/webapp/wcs/stores/servlet/ProductDispl
Any expert inputs?
* Amperage (amps) : 25 A
* Assembled Depth (in.) : 23.5 in
* Assembled Height (in.) : 18 in
* Assembled Width (in.) : 17 in
* Auto idle control : Yes
* Automatic Voltage Regulation : Yes
* Built-in inverter : No
* CSA Listed : No
* ETL Listed : No
* Electrical Produ... 阅读全帖 |
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w*******y
发帖数: 60932 | 37 Amazon has Apple iPod touch 8G (4th Generation) + $30 Amazon MP3 Credit for
$ 189.98.
Link:
http://www.amazon.com/Apple-iPod-touch-8GB-Generation/dp/B001FA
Promotional offer is valid from December 12, 2011 through December 16, 2011
at 11:59 PM PST.
To Qualify:
1. Add at least one qualifying 8GB iPod touch to your Shopping Cart and
complete the purchase. The items that qualify are 8GB iPod touch products in
the Amazon.com store that display the offer message on their product
information pages.
Up... 阅读全帖 |
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w*******y
发帖数: 60932 | 39 Jomashop Link:
http://www.jomashop.com/montblanc-ballpoint-7385.html
has the Montblanc Generation Black Ballpoint Pen for $152 + tax
use code xclsv10 for an extra $10 off, shipping is free.
Montblanc Generation Black Ballpoint Pen:
Ballpoint pen with twist mechanism.
Black precious resin cap and barrel.
Mont blanc white star on cap.
Trim Platinum-plated rings with embossed logo Platinum-plated clip.
Black ink included.
Refills are interchangeable.
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w*******y
发帖数: 60932 | 43 Star Trek: The Next Generation - Next Level [Blu-ray]:
http://www.amazon.com/dp/B0064NLQYG
Pre-order Price Guarantee of $14.99. This title will be released on January
31, 2012.
For the first time ever, you can experience Star Trek: The Next Generation's
most important and beloved episodes in 1080p high definition, with true
high definition visual effects and digitally remastered 7.1 sound - or with
the original audio. The visual effects have been painstakingly re-created
from the original film e... 阅读全帖 |
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G*******s
发帖数: 10605 | 46 【 以下文字转载自 SmartShopper 俱乐部 】
发信人: GoRockets (火箭加油), 信区: SmartShopper
标 题: iPad 3rd Generation 64GB with Wi-Fi $549.99
发信站: BBS 未名空间站 (Tue Dec 4 15:04:47 2012, 美东)
BestBuy has Apple iPad 3rd Generation 64GB White or Black for $549.99 with
free store pickup.
http://userquote.com/forum/index.php?topic=1648.msg1929#msg1929 |
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G*******s
发帖数: 10605 | 47 【 以下文字转载自 SmartShopper 俱乐部 】
发信人: GoRockets (火箭加油), 信区: SmartShopper
标 题: Apple iPad 3rd Generation 16GB $405.99
发信站: BBS 未名空间站 (Thu Mar 28 23:12:06 2013, 美东)
BestBuy Clearance has Apple iPad MD369LL/A (16GB, Wi-Fi + 4G, White) 3rd
Generation for $405.99 with free store pickup.
http://userquote.com/forum/index.php?topic=1826 |
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s*****t
发帖数: 1994 | 48 Next-Generation Space Telescope Chosen to Peer Into Past
By WARREN E. LEARY
WASHINGTON, Sept. 10 NASA chose a successor to the Hubble Space Telescope
today, announcing that it would launch a next-generation space observatory in 2010
that would study light produced in the earliest days of the universe.
The space agency selected TRW Inc., of Redondo Beach, Calif., to lead a team that will build
the observatory, which will be called the James Webb Space Telescope in honor of a
pioneering NASA |
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h****g
发帖数: 312 | 49 C O N F I D E N T I A L SECTION 01 OF 04 BEIJING 001760
SIPDIS
SIPDIS
EO 12958 DECL: 03/15/2032
TAGS PGOV, PREL, ECON, SOCI, CH
SUBJECT: FIFTH GENERATION STAR LI KEQIANG DISCUSSES
DOMESTIC CHALLENGES, TRADE RELATIONS WITH AMBASSADOR
REF: SHENYANG 26
Classified By: Ambassador Clark T. Randt, Jr. Reasons 1.4 (b) and (d).
Summary |
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c**i
发帖数: 6973 | 50 【 以下文字转载自 Hardware 讨论区 】
发信人: choi (choi), 信区: Hardware
标 题: 2nd-Generation GPS on the Way
发信站: BBS 未名空间站 (Sun May 23 13:12:48 2010, 美东)
WJ Hennigan, GPS is getting an $8-billion upgrade; Improvements, including
the replacement of satellites, aim to make the system more reliable, more
widespread and much more accurate. Los Angeles Times, May 23, 2010.
http://www.latimes.com/business/la-fi-gps-20100523,0,3054578.story
Note:
(1) El Segundo, California
http://en.wikipedia.org/wiki/El_Segundo,_Cali |
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