v****n
发帖数: 7841 | 1 看起来不错, 不用温控不用摇. 还可以批量生产, 多弄几个罐子丢在那儿, 爱干嘛干嘛去, 一小时以后收
工.
原帖:
http://www.rangefinderforum.com/forums/showpost.php?p=927796&po
Films that are shot at speed - 35mm -
Several minute water bath
Rodinal 1:100 - disregard temperature unless extreme heat or cold
1 minute of slow inversions, maybe 20 in 60 secs
3 really hard thumps to dislodge air bubbles, very important
DO NOT TOUCH for 59 minutes, a couple minutes extra will not harm anything(
the DO NOT TOUCH is very,
very important)
3 water baths then ... 阅读全帖 |
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a*******l
发帖数: 2353 | 3 hehe, you are talking about Inversion.
as art said , if you are just a beginner, all you need is to remember some
basic chord shapes. and Transpose it to different keys.
for a C chord, only need to know chord with open string, III position and
VIII position.
for a C7 chord, I position, III position, and VIII position.
Cmaj7,min min7,Maj6,min6, or what ever.
one reason people use Inversion is because it could connect the Bass notes
fluently . but it happens more with slash chords. which is conve |
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a*t
发帖数: 2596 | 4 Whoops?!I checked again, you are right.
but if my memory serves me well, this kind
of chord is the alternative way to inverse chord.
the music theory behind shuold be chord inverse,
but I can not figure out how it works now. |
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F*****n
发帖数: 1552 | 5 来自主题: EnglishChat版 - 问个弱问题 数学上的倒数是不是inverse?
矩阵的逆好像也是inverse? |
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H********g
发帖数: 43926 | 6 【 以下文字转载自 Biology 讨论区 】
发信人: lyray (lyray), 信区: Biology
标 题: 人类灵魂就隐藏在DNA末端krypton原子
发信站: BBS 未名空间站 (Wed Aug 26 16:32:06 2015, 美东)
We owe the discovery of this mysterious biogenetic process to our scientist
AOYOO 221.
It had been discovered a long time before that in the human brain were
krypton atoms (a rare gas that you know), and this discovery was a
significant, transcendent one. It was quite simply the key to the OEMBUAW,
MAN'S THIRD FACTOR, which you do not know and which acts as a link be... 阅读全帖 |
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L****o
发帖数: 1642 | 7 赞。希望能康复。NASA 的火星探测器着陆后也曾出过故障，就是控制的vxWorks程序不
停地重启计算机，后来地面的软件工程师们发现是因为多线程软件里某个线程的
priority inversion引起的，使得其他本来有更高优先权的线程被抑制而无法运行，程
序修改后通过无线升级解决了这个问题。现在vxWorks允许设置线程属性为priority
inversion safe来避免这样的问题出现。 |
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s**r
发帖数: 255 | 8 1) I do not agree with soliton.
I do not agree with your 1/0 infinite point. A filter's transfer function
can have zeros and poles. At the poles, the transfer function goes to
infinite, that's reasonalbe. When you take inverse of the transfer
function, zeros become poles, poles become zeros. You got another
filter's transfer function, no problem.
2) I do not agree with JVC either
Even if the low pass filter has the component of e^(-wt0), I can take
out this component before I do inverse. So afte |
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N**D
发帖数: 10322 | 9 what is your goal of computing the inverse?
most of time, you don't need the explicit form of the inverse. |
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F*******X
发帖数: 143 | 10 Framework 有特征 inversion of control， 就是这“inversion of control”让我感
觉莫名其妙的，如果我要用 Framework 在 Server 方面的，那这 Framework 和 API
里面的 Collection Framework 有什么差。
还有你说的“framework比function, library更大”，那“大”是怎么定义了？那我放
很多东西文件在library里面把她做很大，那我可以说“library 比 Framework 大”吗？ |
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w**w
发帖数: 100 | 11 有道理，那只要 inverse A, 有什么好办法么？
好像时间主要花在 inverse A 上了？
我土，只用 python. matlab, 看看你说的库 python 有末有。
多谢大牛 |
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a*****e
发帖数: 1700 | 12 核心问题出在 inversion of control。
更早的（比如 X window）就不说了，单是 callback 方式从 windows 3.0 的时候就流
行（且退流行）过。设计语言的人（比如说 nodejs 的设计者），如果不吸取历史教训
，注定要掉进前人踩过的坑里。nodejs 所倡导的 non-blocking/async programming
就是一个不折不扣的谎言。
解决 inversion of control 方法有很多，但基本原理都是一样的。利用
continuation 构建 co-routine 和 event-driven 的互换，因为两者等价（这个也被
证明过)。而 continuation 这种概念从 Lisp 开始就已经被 FP 玩透了。在所谓的主
流语言里，但凡不支持它的，最后都不得不通过各种方式来弥补，成为各种各样的半调
子框架，which unfortunately is the sad truth of status-quo.
建议使用 nodejs 的同学都先来学习一下它的坑：
http://notes.ericjiang.com/p... 阅读全帖 |
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a*****e
发帖数: 1700 | 13 我什么时候说过 inversion of control 和 async 有关系？我说的是：
1. "callback 反人类" 是因为 "inversion of control"
2. nodejs 鼓吹的 async programming 和 callback 没有一毛钱关系，用 co-routine
一样可以做 async，而且早很多年就被做过了。强迫用户使用 callback 是 nodejs
的设计者脑残。
3. continuation 是实现 co-routine 和 event-driven 之间转换的核心方法。你前面
说的 promise 和 generator 什么的，都属于 imitation of co-routine |
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a*****e
发帖数: 1700 | 14 一定程度上的 hair splitting 也是有意义的。至少我现在明白你说的 IoC is
strictly in a OO sense。
如果我们追溯一下 IoC 这个词的起源，wiki 上给出的是 Martin Fowler 的博文:
http://martinfowler.com/bliki/InversionOfControl.html
里面提到:
"There is some confusion these days over the meaning of inversion of control
due to the rise of IoC containers; some people confuse the general
principle here with the specific styles of inversion of control (such as
dependency injection) that these containers use. The name is somewhat
confusing ..."
我使用 IoC 这个词的原意和 F... 阅读全帖 |
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r*****l
发帖数: 457 | 18 next next generation sequencing出来以后，瓶颈就在于硬件了
几百个marker做矩阵inverse和百万个做inverse，区别就不说了
GLM也许还可以，MLM估计超级计算机也够呛吧 |
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B******w
发帖数: 1040 | 19 比如说loxp2272 序列： ATAACTTCGTATA-AaGTATcC-TATACGAAGTTA。。。。。
ATAACTTCGTATA-AaGTATcC-TATACGAAGTTA 会导致deletion
ATAACTTCGTATA-AaGTATcC-TATACGAAGTTA。。。。。。。TAACTTCGTATA-GgATACtT-
TATACGAAGTTAT会导致inversion
那TAACTTCGTATA-GgATACtT-TATACGAAGTTAT。。。。。。ATAACTTCGTATA-AaGTATcC-
TATACGAAGTTA会同样导致inversion吗
不好意思，有点迷糊，问题可能太傻了 |
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l***y
发帖数: 1166 | 20 We owe the discovery of this mysterious biogenetic process to our scientist
AOYOO 221.
It had been discovered a long time before that in the human brain were
krypton atoms (a rare gas that you know), and this discovery was a
significant, transcendent one. It was quite simply the key to the OEMBUAW,
MAN'S THIRD FACTOR, which you do not know and which acts as a link between
the HEART and the BODY (BUAWAA and OEMII).
69 XEE before [approximately 18 months NdT ], in laboratory fertilization
experime... 阅读全帖 |
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f***8
发帖数: 571 | 21 我有个办法，稍微麻烦点，但是可以用Action自动处理，PS高手轻砸
1. 图片打开后，首先在Actions panel（右上角）里创建一个新的Action，并开始录制。
2. 选择Magic wand tool，tolerance=30，mode="Add To Selection"，然后点选图片
左上角的黑色背景
3. 在Select菜单下，先选择Inverse，再选择Contract=15 px,再选择Expand=22 px。
（这一步选择了除了虚线以外的其他分子结构）
4. 再次使用Magic wand tool，点选左上角的黑色背景，然后选择Select->Inverse。
(这一步选择了所有虚线)
5. 再次选择Select->Expand(4 px)，然后Select->Feather(3 px),调节background
color为你需要的绿色，按Ctrl+回车进行填充。（这一步加粗了虚线，并对边缘略加虚
化后填充）
6. 大功告成，在Actions panel里选择停止录制，然后就可以运行这个Action自动处理
其他图片了。
效果如图 |
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C********5
发帖数: 194 | 22 In your case, there are k_dissociation and k_pre-dissociation, in addition
to k_ic, k_isc, and k_quenching.
k_nr generally decreases as energy gap increases. I saw linear inverse, also
square inverse relationships with energy gap. There may be a negative
exponential relationship. I guess this is a case-by-case question.
To answer your first question, both k_r and k_nr decrease, and k_r decreases
faster than k_nr. So you see less fluorescence. This is also why pi-
conjugated system usually has st... 阅读全帖 |
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c*******a
发帖数: 18 | 23 I think that can be solved in this way.
let A be your equation matrix
X be your parameters, B is your result vector
so AX = B
Where A is a 10,000x100 matrix, X is a 100x1 matrix
B is a 10,000x1 matrix
we need to solve x, so we multiply A'(A transpose to both side)
we get (A'A)X=A'B
Now A'A becomes a 100x100 square matrix,so we can calculate the inverse
multiply the inverse on both side
we get X=(A'A)^(-1) A'B
That is just a illustration of the method, there should be more
efficient method to ac |
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h***z
发帖数: 233 | 24 How does your matrix change between iterations? If the change is low rank,
you can use the Woodbury formula to quickly update the inverse of the new
matrix based on the inverse of the old matrix.
的c |
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c*****a
发帖数: 16 | 26 【 以下文字转载自 Statistics 讨论区 】
发信人: cdsdata (CDS), 信区: Statistics
标 题: Heckman two-step
发信站: BBS 未名空间站 (Sun Jan 20 10:31:48 2013, 美东)
First step: run a probit equation of participation using all the
observations. The estimates of from this probit model are then used to
construct consistent estimates of the inverse Mills ratio term.
Second step: Include the inverse Mills ratio and run the original regression
equation.
Question: do these two equations have to include the SAME control variables
(exce... 阅读全帖 |
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l******f
发帖数: 32 | 27 假如 A, B are both n-by-n matrix. And B > A > 0. Furthermore, A and B are
both symmetric and non-singular.
inverse( A ) > inverse( B ) is established or not?
非常感谢！ |
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p******h
发帖数: 577 | 28 If winded on the same leg of core, for example center leg, and the 100%
coupling can be assumed. Then it depends on whether it is coupling or
inverse coupling. If it is coupling, then the final inductance is same. If
it is inverse coupling, then ideally, the inductance becomes zero.
or
... |
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y********g
发帖数: 81 | 29 1.Current and load cap. Its current is a
function of length, width, bias, etc.
2. 45nm, 32nm is half pitch dimension. This
is not transistor physical gate length nor
effect channel length. Refer to device
physics for detail.
3. 1/rate? how do you define resolution?
4. NMOS is stronger than PMOS in term of
larger current under the same condition.
NMOS conducts electron current whereas PMOS
conducts hole current. Whichever carrier it
is, current is proportional to mobility.
mobility is inverse pro... 阅读全帖 |
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m****o
发帖数: 27 | 30 帮朋友转发清华大学博士后机会
Post doctor in Electrical Tomography based Subsea Gas oil water
Multiphase Flow Metering
Graduate School at Shenzhen, Tsinghua University, China
Division of Ocean Science and Technology in Tsinghua University now is
looking for 1 to 2 two years post doctor in research on Electrical
tomography
based subsea gas﹐il﹚ater multiphase flow metering. The working location
will be in Shenzhen campus but frequently travel to Beijing.
http://www.sz.tsinghua.edu.cn/
The major research includ... 阅读全帖 |
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l***u
发帖数: 1 | 31 1. Fourier Inversion Theorem
Th: If \int_{-\inf}^{\inf} \abs(g_{X}(t))dt <\inf, then X is absolutely
continuous with density
f(x)=1/(2*pi) \int_{\-inf}^{\inf} exp(-itx) g(t)dt
2. The Ch. f. of Laplace distribution, which has density is 1/2*exp(-\abs(x)),
is
g(t)=1/(1+t^2)
This is easy to verify by standard calculation.
3. So, by Fourier Inversion Theorem,
1/2*exp(-\abs(x))=1/(2*pi) \int_{\-inf}^{\inf} exp(-itx)*1/(1+t^2) dt
=1/(2*pi) \int_{\-inf}^{\inf} exp(itx)*1/(1+t^2) dt
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y**t
发帖数: 50 | 32 from left to right, inverse L.T., choose carefully the curve consisting
of a vertical line, a near semicircle (towards left) and two near semilines
(one end is -infinity) just below and above the real axis
with 2 tiny semicircles and a tiny circle around -a and -b. Now the inverse
L.T. becomes 4 integrals, combine them together and you reach the rhs.
from right to left, L.T., easy done by variable substitution. |
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e***e
发帖数: 5 | 33 最近发现inverse和reverse的用法都开始混淆了.好像矩阵的逆是inverse. reverse是不
是符号相反? 这两个词在数学中是否可以互换? |
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H****h
发帖数: 1037 | 34 Very simple.
How about this:
if the left inverse exists, then the right inverse also exists,
and vice visa. |
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l******f
发帖数: 32 | 35 假如 A, B are both n-by-n matrix. And B > A > 0. Furthermore, A and B are
both symmetric and non-singular.
inverse( A ) > inverse( B ) is established or not?
非常感谢！ |
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p*****g
发帖数: 41 | 36 大家好，我试着用 Mathematic 来解 AX=B 的矩阵方程, 结果返回 "Inverse::"luc":
"Result for Inverse of badly conditioned matrix may contain significant
numerical errors. 用MathCAD解，求出的A-1和A相乘后，却不为单位矩阵。我求了一
下Determinant, 很小,10^-48左右，不知是不是这个原因。
具体的矩阵在附件中，我不是数学专业的，不知道还有什么方法可以解，请各位帮忙。
多谢！ |
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l*****a
发帖数: 119 | 37 求inverse 首先做一个LU, 之后做n个backsolve 每个backsolve是O(n^2) n个加起
来就是O(n^3) 简单说, 求inverse 和做LU是一个数量级上的, 常数可能大个两三倍
的样子, 具体不记得了 |
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J*******g
发帖数: 267 | 38 来自主题: Mathematics版 - 问个问题 【 以下文字转载自 Quant 讨论区 】
发信人: JackSheng (重新振作), 信区: Quant
标 题: 问个问题
发信站: BBS 未名空间站 (Sat May 16 22:59:30 2009), 转信
证明matrix inversion和matrix multiplication是equivalent in terms of
complexity？
I can show one direction (realize matrix multiplication using matrix
inversion) but got stuck on the other direction. Someone assured me that
the other direction is true too. Any thoughts? |
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c*******v
发帖数: 2599 | 39 A(x)*P=f(x)
f(x)是函数在chebyshev grids的值.x是chebyshev grids.P是要求的系数.
显然,A(x)是一个和函数f无关的矩阵.
所以inverse A可以预先算好放起来,对所有函数通用.
这个求逆通常是不计入计算时间的.我怀疑这个A(x),inverse A(x)
有很不错的表达式。
同样的数据量FFT好像是n*log(n)，求逆是n^3。但是如果你的目的
是函数逼近，那么用三角函数做基(fft)比Chebyshev要采样多得多的点。
而且三角函数不保证一致误差。 |
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g*****h
发帖数: 15 | 40 College Algebra by Larson & Hostetler
DVDRip | MKV / AVC 692 Kbps | 720х544 | 29.97 fps | MP3 128 kbps | 8.75 GB
Language: English
Lecture Titles:
Prerequisites
P-1 Review of Real Numbers and Their Properties
P-2 Exponents and Radicals
P-3 Polynomials and Special Products
P-4 Factoring
P-5 Rational Expressions
P-6 Errors and the Algebra of Calculus
P-7 Graphical Representations of Data
Chapter 1 – Equations and Inequalities
1-1 Graphs of Equations
1-2 Linear Equations in in One Variable
1-3 Mode... 阅读全帖 |
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n*********3
发帖数: 534 | 41 I see A lot of books places say that Euler solved the Basel problem. But
they only show the results, and not how.
Can anyone show how?
Lookacar and others?
"Notably, Euler directly proved the power series expansions for e and the
inverse tangent function. (Indirect proof via the inverse power series
technique was given by Newton and Leibniz between 1670 and 1680.) His daring
use of power series enabled him to solve the famous Basel problem in 1735 (
he provided a more elaborate argument in 1741)... 阅读全帖 |
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s*h
发帖数: 1538 | 42 我从资料上copy的，希望对你有用。我自己是脑袋昏的。
Acute Pericarditis (see ECG below)
Concave upwards ST elevation in most leads except aVR
No reciprocal ST segment depression (except in lead aVR)
Unlike "early repolarization", T waves are usually lower in
amplitude, and heart rate
is usually increased.
May see PR segment depression, a manifestation of atrial injury
Example: Post-op pericarditis; note diffuse, concave-upwards ST elevation,
HR 100 bpm, PR
segm... 阅读全帖 |
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h********g
发帖数: 5 | 43 Ming Liu and Fuqian Yang, Finite element simulation of the effect of
electric boundary conditions on the spherical indentation of transversely
isotropic piezoelectric films, Smart Materials and Structures 21 (2012)
105020 (10pp)
Finite element simulation was used to analyze the effect of electric
boundary conditions on the
indentation deformation of a transversely isotropic piezoelectric film
with the contact radius
much larger than the film thickness. Six different combinations of... 阅读全帖 |
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m*********3
发帖数: 1425 | 44 160B$的大deal,总部会设在爱尔兰，估计马上又要大裁人了
http://www.reuters.com/article/2015/11/23/us-allergan-m-a-pfize
Pfizer Inc on Monday said it would buy Botox maker Allergan Plc in a deal
worth $160 billion to slash its U.S. tax bill, rekindling a fierce political
debate over the financial maneuver.
The acquisition, which would create the world's largest drugmaker and shift
Pfizer's headquarters to Ireland, would also be the biggest-ever instance of
a U.S. company re-incorporating overseas to lower its taxes. U.S... 阅读全帖 |
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p*x
发帖数: 260 | 45 For equity prices, brownian motion by no means produces good results.
A possible improvement would be Normal Inverse Gaussian process coupled with
Inverse Gaussian Bridge technique.
In terms of MC simulation, you would be able to further improve your results
by the stratified sampling method.
Good luck. |
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g****e
发帖数: 1829 | 46 Fourier inversion is not complicated. it is fast and easy to implement. If
you use Monte-Carlo, be sure to find a good measure to reduce the variance,
or find a good quasi method, which can be tricky.
杂的用什么fourier inversion, charactersitics function去推导price formula的，
看得我头晕。能用simulation的方便去模拟stock price dynamics under risk
neutral measure无数遍然后把每次得到的option payoff平均下来当成option price么
？这样的结果精确么？
volatility jump，两个jump size是linearly correlated. Jump arrival rate 是
lambda*V_t, lambda是个positive constan... 阅读全帖 |
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i***6
发帖数: 442 | 47 是股票投资组合，而且只是对冲一部份的downside,并不想完全hedge。想到的工具有：
1、买各股的put option；
2、卖空delta one index etf；
3、买inverse index etf；
4、卖空leveraged index etf；
5、买inverse leveraged index etf。
个人当前偏好1和4。选项1比较理想，但是缺历史数据，回溯测试比较困难。
各位大侠有什么高见？ |
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l**********e
发帖数: 336 | 48 thank you so much~~Inverse Mills ratio这个概念没有听说过，去看看
btw，Inverse Mills ratio给出的这个解里面，还是带有normal的c.d.f函数，这个部
分还是算没有closed-form？～～
是不是如果要给一定bound E(Z|Z>a)，到最后其实还是回避不开bound高斯的c.d.f呢？ |
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L*******t
发帖数: 2385 | 49 有些recovery，impose一些structural model，这些有经济含义，但是具体表现怎样不
知道。
也有些recovery是pure data driven的，这些个我觉得虽然理论漂亮但不怎么靠谱。
上次看了Rama Cont的一篇文章，inverse problem on option pricing的，理论结果很
漂亮，但凡是没有给numerics。
估计option pricing会更受大家喜欢一点。
我在想的问题是，是否有一种结合structural form和reduced form的方法来做这个问
题？我对PDE和FBSDE的inverse problem不太了解，隐约地觉得可能会用到。 |
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r***a
发帖数: 58 | 50 U is column orthogonal, the elements of S are positive or zero,
and V'V=I.
Singular value decomposition is used to obtain accurate inverses
of nearly singular matrices and to obtain g2-inverses of matrices
which are singular, to construct orthonormal bases, and to develop
approximation matrices |
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