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small. by putting many of these out and back combinations together, you can get a useful voltage. a single out and back is called a thermocouple, and can be used to sense temperature. many together is a thermocouple generator. yes, those actually exist. there have been spacecraft powered on this principle with the heat... | https://api.stackexchange.com |
according to martin chaplin's water dissociation and ph : in ice, where the local hydrogen bonding rarely breaks to separate the constantly forming and re - associating ions, the dissociation constant is much lower ( for example at $ - 4 ~ \ mathrm { ^ \ circ c } $, $ k _ \ mathrm { w } = 2 \ times 10 ^ { - 20 } ~ \ ma... | https://api.stackexchange.com |
i always though that $ \ mu $ - recursive functions nailed it. here is what defines the whole set of computable functions ; it is the smallest set of functions containing resp. closed against : the constant $ 0 $ function the successor function selecting parameters function composition primitive recursion the $ \ mu $ ... | https://api.stackexchange.com |
there exist problems that are hard to solve, but for which it is easy to verify the validity of a given solution : the so called np problems. this statement is wrong. there are many np problems which are easy to solve. " np " simply means " easy to verify ". it does not mean hard to solve. what you are probably thinkin... | https://api.stackexchange.com |
just ask her what the voltage across the resistor is | https://api.stackexchange.com |
i have thought about this some more, and think that the following should be fairly stable. note that i have limited myself to morphological operations, because these should be available in any standard image processing library. ( 1 ) open image with a npix - by - 1 mask, where npix is about the vertical distance betwee... | https://api.stackexchange.com |
##wmorph ( opimg,'skel ', inf ) ; % # prune the skeleton a bit to remove branches sk = bwmorph ( sk,'spur ', 7 ) ; riverswithwidth = dt. * sk ; ( colors correspond to width of river ( though color bar is off by a factor of 2 ) now you can get the approximate length of the rivers by counting the number of pixels in each... | https://api.stackexchange.com |
is this a valid way of introducing speed estimates into the process? if you choose your state appropriately, then the speed estimates come " for free ". see the derivation of the signal model below ( for the simple 1 - d case we've been looking at ). signal model, take 2 so, we really need to agree on a signal model be... | https://api.stackexchange.com |
; q = sigma _ a ^ 2 ; r = 0. 1 ; n = 1000 ; a = rand ( 1, n, " normal " ) * sigma _ a ; x _ truth ( :, 1 ) = x0 ; for t = 1 : n, x _ truth ( :, t + 1 ) = f * x _ truth ( :, t ) + g * a ( t ) ; y ( t ) = h * x _ truth ( :, t ) + rand ( 1, 1, " normal " ) * sqrt ( r ) ; end then, i can apply the kalman filter equations t... | https://api.stackexchange.com |
exact measurements mean that $ \ mathbf { z } _ { k + 1 } = x _ { k + 1 } $. if you assume that the initial position and speed are known so that $ \ mathbf { p } _ k = 0 $, then $ \ mathbf { p } _ { k + 1 } ^ { - } = \ mathbf { q } $ and the kalman gain matrix $ \ mathbf { k } _ { k + 1 } $ is given by $ $ \ mathbf { k... | https://api.stackexchange.com |
here is the plyr one line variant using ddply : dt < - data. frame ( age = rchisq ( 20, 10 ), group = sample ( 1 : 2, 20, rep = t ) ) ddply ( dt, ~ group, summarise, mean = mean ( age ), sd = sd ( age ) ) here is another one line variant using new package data. table. dtf < - data. frame ( age = rchisq ( 100000, 10 ), ... | https://api.stackexchange.com |
yes, deconvolution. this page describes a number of deconvolution methods and methods for estimating the point spread function : removing motion blur from astrophotographic images they say the deconvolution literature is " extremely extensive ". they choose lucy - richardson algorithm for deconvolution and develop thei... | https://api.stackexchange.com |
tl ; dr : there is a dearth of actual experimental evidence. however : there is at least one study that confirmed the process ( [ study # 7 ] - myxococcus xanthus ; by fiegna and velicer, 2003 ). another study experimentally confirmed higher extinction risk as well ( [ study # 8 ] - paul f. doherty's study of dimorphic... | https://api.stackexchange.com |
##uda and peter a. abrams ; evolution vol. 48, no. 6 ( dec., 1994 ), pp. 1764 - 1772 : [ study # 3 ] we show that purely intraspecific competition can cause evolution of extreme competitive abilities that ultimately result in extinction, without any influence from other species. the only change in the model required fo... | https://api.stackexchange.com |
, this constitutes the first study making such a prediction from empirical data. in cod, gadus morhua, the commercial fishing of large individuals has resulted in selection towards earlier maturation and smaller body sizes ( conover and munch 2002 [ study # 6 ] ). under exploitation, high mortality decreases the benefi... | https://api.stackexchange.com |
( dichromatic birds had on average a 23 % higher local extinction rate than monochromatic species ). however, despite higher local extinction probabilities, the number of dichromatic species did not decrease over the period considered in this study. this pattern was caused by higher local turnover rates of dichromatic ... | https://api.stackexchange.com |
i am working on a illumina sequencing simulator for metagenomics : insilicoseq it is still in alpha release and very experimental, but given a multi - fasta and an abundance file, it will generate reads from your input genomes with different coverages. from the documentation : iss generate - - genomes genomes. fasta - ... | https://api.stackexchange.com |
allowed by whom? there is no central graph administration that decides what you can and cannot do. you can define objects in any way that's convenient for you, as long as you're clear about what the definition is. if zero - weighted edges are useful to you, then use them ; just make sure your readers know that's what y... | https://api.stackexchange.com |
the answer depends on whether you are dealing with discrete or continuous random variables. so, i will split my answer accordingly. i will assume that you want some technical details and not necessarily an explanation in plain english. discrete random variables suppose that you have a stochastic process that takes disc... | https://api.stackexchange.com |
. thus, in the continuous case we estimate $ \ theta $ given observed outcomes $ o $ by maximizing the following function : $ l ( \ theta | o ) = f ( o | \ theta ) $ in this situation, we cannot technically assert that we are finding the parameter value that maximizes the probability that we observe $ o $ as we maximiz... | https://api.stackexchange.com |
note : that depends on what coordinates you use in the resized image. i am assuming that you are using zero - based system ( like c, unlike matlab ) and 0 is transformed to 0. also, i am assuming that you have no skew between coordinates. if you do have a skew, it should be multiplied as well short answer : assuming th... | https://api.stackexchange.com |
\ frac { m _ 1 p } { m _ 3 p } \ \ v'= ( 1 / 2 ) \ frac { m _ 2 p } { m _ 3 p } $ $ converting back to matrix form gives us : $ $ \ left ( \ begin { array } { ccc } 0. 5 & 0 & 0 \ \ 0 & 0. 5 & 0 \ \ 0 & 0 & 1 \ end { array } \ right ) \ left ( \ begin { array } { ccc } a _ x & 0 & u _ 0 \ \ 0 & a _ y & v _ 0 \ \ 0 & 0 ... | https://api.stackexchange.com |
no, samtools ( and therefore bcftools ) does not use soft - clipped bases. you can quickly confirm this by using either samtools depth or samtools mpileup to look at a region with a soft - clipped alignment. you'll note that the soft - clipped region isn't used in the depth / pileup ( both tools use the same underlying... | https://api.stackexchange.com |
there is no formal definition of " safe programming language " ; it's an informal notion. rather, languages that claim to provide safety usually provide a precise formal statement of what kind of safety is being claimed / guaranteed / provided. for instance, the language might provide type safety, memory safety, or som... | https://api.stackexchange.com |
depends on what you mean by subexponential. below i explain a few meanings of " subexponential " and what happens in each case. each of these classes is contained in the classes below it. i. $ 2 ^ { n ^ { o ( 1 ) } } $ if by subexpoential you mean $ 2 ^ { n ^ { o ( 1 ) } } $, then a conjecture in complexity theory call... | https://api.stackexchange.com |
( n ^ \ frac { 1 } { k } ) } $. iv. $ 2 ^ { o ( n ) } $ this contains the previous class, the answer is similar. v. $ \ bigcap _ { 0 < \ epsilon } 2 ^ { \ epsilon n } $, i. e. $ 2 ^ { \ epsilon n } $ for all $ \ epsilon > 0 $ this contains the previous class, the answer is similar. vi. $ \ bigcup _ { \ epsilon < 1 } 2 ... | https://api.stackexchange.com |
it is uniformly defined. it is similar to $ \ mathsf { exp } $ which uses $ 2 ^ { n ^ { o ( 1 ) } } $. ii is seems to be used in the definition of the complexity class $ \ mathsf { subexp } $. iii is used for algorithmic upper - bounds, like those mentioned in pal's answer. iv is also common. v is used to state the eth... | https://api.stackexchange.com |
you're asking about the technical tradeoffs surrounding the selection of a traction motor for an electric vehicle application. describing the full design tradespace is far beyond what can reasonably be summarized here, but i'll outline the prominent design tradeoffs for such an application. because the amount of energy... | https://api.stackexchange.com |
), net = 88 % - wear / service : brush dc : brushes subject to wear ; require periodic replacement. bearings. bldc : bearings ( lifetime ) induction : bearings ( lifetime ) - specific cost ( cost per kw ), including inverter brush dc : low - motor and controller are generally inexpensive bldc : high - high power perman... | https://api.stackexchange.com |
tend to vary much more with the actual implementation. | https://api.stackexchange.com |
fft is actually not a great way of making a tuner. fft has inherently a finite frequency resolution and it's not easy to detect very small frequency changes without making the time window extremely long which makes it unwieldy and sluggish. better solutions can be based on phase - locked loops, delay - locked loops, au... | https://api.stackexchange.com |
there was a period of time where lots of capacitors were made with a dodgy electrolyte, especially by some large taiwanese manufacturers. the capacitors looked ok in a wide variety of tests when new, but they didn't age well. because it took a few years for the capacitors to fail, and the high failure rate to become kn... | https://api.stackexchange.com |
hypothermia ( when the body is too cold ) is said to occur when the core body temperature of an individual has dropped below 35° celsius. normal core body temperature is 37°c. ( 1 ) hypothermia is then further subdivided into levels of seriousness ( 2 ) ( although all can be damaging to health if left for an extended p... | https://api.stackexchange.com |
affected will eventually literally freeze, causing cell destruction. ( 7 ) similarly to hypothermia, frostbite is divided into four degrees ( that can be viewed on wikipedia ). as to the matter of global warming cooking us to death, i would imagine that it would be more indirect changes that got us first. if the averag... | https://api.stackexchange.com |
well, i think you have a few options. if you have a stable page — such as one sponsored by a university or other non - profit institution that's unlikely to vanish anytime soon — you could publish there. you could use a service like github or bitbucket or sourceforge to distribute the code. if the code is of marginal g... | https://api.stackexchange.com |
$ $ \ ce { r - oh + oh - < = > ro - + h2o } $ $ in alcoholic solution, the $ \ ce { koh } $ is basic enough ( $ \ mathrm { p } k _ { \ mathrm { a } } = 15. 74 $ ) to deprotonate a small amount of the alcohol molecules ( $ \ mathrm { p } k _ { \ mathrm { a } } = 16 – 17 $ ), thus forming alkoxide salts ( $ \ ce { rok } ... | https://api.stackexchange.com |
there is a straightforward solution with only two passes through the data : first compute $ $ k : = \ max _ i \ ; a _ i, $ $ which tells you that, if there are $ n $ terms, then $ $ \ sum _ i e ^ { a _ i } \ le n e ^ k. $ $ since you presumably don't have $ n $ anywhere near as large as even $ 10 ^ { 20 } $, you should... | https://api.stackexchange.com |
if you want to write something general - purpose, you can do it either with shell scripts if it is something very simple, as pedro suggests, or aggregate in a higher - level mathematical programming language such as python or matlab. i agree that plain text files are useful for smaller amounts of data, but you should p... | https://api.stackexchange.com |
steel, having just around 10 times higher resistivity than copper means it will take ten times the conductor area to match copper. if you measured 13 meter of it to 3. 8 ω, the cross sectional area would be 2 mm ^ 2, assuming 5. 95 * 10 ^ - 7 ωm of resistivity for " high alloy steel " ( this varies greatly unfortunatel... | https://api.stackexchange.com |
the main reason is because you can't safely connect diodes in parallel. so when we use one resistor, we have a current limit for the whole diode section. after that it's up to each diode to control the current that goes through it. the problem is that real world diodes don't have same characteristics and therefore ther... | https://api.stackexchange.com |
step 1 ) identify the package, note how many pins, match up the pins first. note that sometimes the package pins are underneath the part or extended away from the part. also get the dimensions of the part with a ruler or ( preferably ) calipers and match them up with a chart, write them down for a later step. one way y... | https://api.stackexchange.com |
the opamps with 5 pin packages. then start checking datasheets as most of the leading manufactures provide smt codes in datasheets with the package information. if it is an old part, a search through old datasheets or maybe an email to the manufacturer might be the way to clarify the part. many manufacturers have also ... | https://api.stackexchange.com |
maxwell's equations do follow from the laws of electricity combined with the principles of special relativity. but this fact does not imply that the magnetic field at a given point is less real than the electric field. quite on the contrary, relativity implies that these two fields have to be equally real. when the pri... | https://api.stackexchange.com |
the $ x $ - direction, you mix the time coordinate $ 0 $ with the spatial $ x $ - coordinate $ 1 $. consequently, a part of the $ f _ { 03 } $ field is transformed into the component $ f _ { 13 } $ which is interpreted as the magnetic field $ b _ y $, up to a sign. alternatively, one may describe the electricity by the... | https://api.stackexchange.com |
what's the difference between ( ~ 1 +.... ) and ( 1 |... ) and ( 0 |... ) etc.? say you have variable v1 predicted by categorical variable v2, which is treated as a random effect, and continuous variable v3, which is treated as a linear fixed effect. using lmer syntax, simplest model ( m1 ) is : v1 ~ ( 1 | v2 ) + v3 th... | https://api.stackexchange.com |
v4 effect from p3 in each level of v2 p8 : deviations of the v3 - by - v4 interaction from p4 in each level of v2 p9 correlation between p5 and p6 across levels of v2 p10 correlation between p5 and p7 across levels of v2 p11 correlation between p5 and p8 across levels of v2 p12 correlation between p6 and p7 across leve... | https://api.stackexchange.com |
1. there is a difference in terms of optimality criteria kalman filter is a linear estimator. it is a linear optimal estimator - i. e. infers model parameters of interest from indirect, inaccurate and uncertain observations. but optimal in what sense? if all noise is gaussian, the kalman filter minimizes the mean squar... | https://api.stackexchange.com |
in 1970, h. w. sorenson published an ieee spectrum article titled " least - squares estimation : from gauss to kalman. " [ see ref 3. ] this is a seminal paper that provides great insight about how gauss'original idea of least squares to today's modern estimators like kalman. gauss'work not only introduced the least sq... | https://api.stackexchange.com |
can be treated within the least squares framework. 3. they are same as far as causality direction of prediction is concerned ; besides implementation efficiency sometimes it is perceived that kalman filter is used for prediction of future events based on past data where as regression or least squares does smoothing wit... | https://api.stackexchange.com |
we all know that \ begin { equation } \ exp ( x ) = \ sum _ { n = 0 } ^ \ infty \ frac { x ^ n } { n! } = 1 + x + \ frac12 x ^ 2 + \ dots \ end { equation } implies that for $ | x | \ ll 1 $, we have $ \ exp ( x ) \ approx 1 + x $. this means that if we have to evaluate in floating point $ \ exp ( x ) - 1 $, for $ | x ... | https://api.stackexchange.com |
) - 1 $ for small $ x $. using it for general $ x $ is not harmful, since expm1 is expected to be accurate over its full range : > > > exp ( 200 ) - 1 = = exp ( 200 ) = = expm1 ( 200 ) true ( in the above example $ 1 $ is well below 1ulp of $ \ exp ( 200 ) $, so all three expression return exactly the same floating poi... | https://api.stackexchange.com |
of your three " thoughts ", you are correct that an aldol reaction is not an option. not only is the product " crowded ", but the reaction is reversible. [ btw, an aldol condensation occurs when water is eliminated from the initial aldol product. in the case of a benzoin aldol product, elimination of water is impossibl... | https://api.stackexchange.com |
first, let us remark that there exist several hundred read mappers, most of which have been even published ( see, e. g., pages 25 - 29 of this thesis ). developing a new mapper probably makes sense only as a programming exercise. whereas developing a quick proof - of - concept read mapper is usually easy, turning it in... | https://api.stackexchange.com |
the meaning of that formula is really quite simple. imagine you take two same - sized small areas of an image, the blue one and the red one : the window function equals 0 outside the red rectangle ( for simplicity, we can assume the window is simply constant within the red rectangle ). so the window function selects wh... | https://api.stackexchange.com |
s the kind of patch a corner - detector is looking for. many references say it is the magnitude by which the window'w'shifted... so how much is the window shifted? one pixel... two pixels? normally, you don't calculate e ( u, v ) at all. you're only interested in the shape of it in the neighborhood of ( u, v ) = ( 0, 0... | https://api.stackexchange.com |
in order : because the term " gauge symmetry " pre - dates qft. it was coined by weyl, in an attempt to extend general relativity. in setting up gr, one could start with the idea that one cannot compare tangent vectors at different spacetime points without specifying a parallel transport / connection ; weyl tried to ex... | https://api.stackexchange.com |
| b \ right \ rangle $ $ where $ a $ is any physical observable. " gauge " symmetries are those where we decide to label the same state $ \ left | \ psi \ right \ rangle $ as both $ a $ and $ b $. in classical mechanics, both are represented the same way as symmetries ( discrete or otherwise ) of a symplectic manifold.... | https://api.stackexchange.com |
the same ( carefully ) commuting superselection with gauge fixing. | https://api.stackexchange.com |
first of all, let me make it clear that the heart is at the vertical centre of the body - - it is not shifted towards left ( or right ). however, it is slightly tilted towards the left in most cases. in some cases, it is tilted towards the right, and the condition is called dextrocardia. for why it is so, lets look at ... | https://api.stackexchange.com |
one side, it becomes difficult to make it symmetrical. ( the only option imo is to have another pointed end at the right side. ) in this case again, what advantage would a symmetrical heart provide? none. and it might even be harmful since having an even bigger heart would mean making both lungs smaller. thus, a symmet... | https://api.stackexchange.com |
" electricity " is not a thing, more like a concept. " amount of electricity " does not have a real meaning. you can have some specified amount of power, voltage, current, or other measurable properties, but not " electricity ". for those that don't fully understand current, voltage, and power, it is best to just avoid... | https://api.stackexchange.com |
tl ; dr : the $ \ ce { o - o } $ and $ \ ce { s - s } $ bonds, such as those in $ \ ce { o2 ^ 2 - } $ and $ \ ce { s2 ^ 2 - } $, are derived from $ \ sigma $ - type overlap. however, because the $ \ pi $ and $ \ pi ^ * $ mos are also filled, the $ \ pi $ - type overlap also affects the strength of the bond, although th... | https://api.stackexchange.com |
are the two $ \ mathrm { p } _ z $ orbitals. the extent to which the $ \ sigma $ mo is stabilised depends on an integral, called the overlap, between the two $ n \ mathrm { p } _ z $ orbitals ( $ n = 2, 3 $ ). formally, this is defined as $ $ s ^ { ( \ sigma ) } _ { n \ mathrm { p } n \ mathrm { p } } = \ left \ langle... | https://api.stackexchange.com |
at oxygen and sulfur would be doing ourselves a disservice. so let's look at how the trend continues. $ $ \ begin { array } { | c | c | c | c | } \ hline \ mathbf { x } & \ mathbf { bde ( x - x ) \ / \ kj \ mol ^ { - 1 } } & \ mathbf { x } & \ mathbf { bde ( x - x ) \ / \ kj \ mol ^ { - 1 } } \ \ \ hline \ ce { o } & 1... | https://api.stackexchange.com |
\ pi ^ * $ orbitals generate a net bonding effect. ( after all, this is where the second " bond " comes from. ) since the $ \ pi $ - $ \ pi ^ * $ splitting is much larger in $ \ ce { o2 } $ than in $ \ ce { s2 } $, the $ \ pi $ bond in $ \ ce { o2 } $ is much stronger than the $ \ pi $ bond in $ \ ce { s2 } $. so, in t... | https://api.stackexchange.com |
answering my own question after reading the 2018 nature review article “ mrna vaccines — a new era in vaccinology ” the resources and motivation engendered by the covid - 19 pandemic are a major factor in the development of the first mrna vaccines approved by national governments. however, before the covid - 19 pandemi... | https://api.stackexchange.com |
, as well as enrichment of g : c content16, have been examined for increasing in vivo protein expression. 2. progress in mrna vaccine delivery there are numerous delivery methods for mrna vaccines that have been examined in the literature. in recent years, the limitations of some of these, such as using physical method... | https://api.stackexchange.com |
, m., zhang, z., gong, t. & sun, x. induction of hiv ‑ 1 gag specific immune responses by cationic micelles mediated delivery of gag mrna. drug deliv. 23, 2596 – 2607 ( 2016 ). li, m. et al. enhanced intranasal delivery of mrna vaccine by overcoming the nasal epithelial barrier via intra - and paracellular pathways. j.... | https://api.stackexchange.com |
##6 – 1464 ( 2015 ). kariko, k., muramatsu, h., ludwig, j. & weissman, d. generating the optimal mrna for therapy : hplc purification eliminates immune activation and improves translation of nucleoside - modified, protein - encoding mrna. nucleic acids res. 39, e142 ( 2011 ). gustafsson, c., govindarajan, s. & minshull... | https://api.stackexchange.com |
" a few " 100kb reads won't help much. you need to apply the ultra - long protocol, which is different from the standard protocol. you can't resolve 20kb near identical repeats / segdups with 10kb reads. all you can do is to bet your luck on a few excessively long reads spanning some units by chance. for divergent copi... | https://api.stackexchange.com |
what you are asking for is the elsivier grand challenge of the " executable paper ". while many approaches have been tried, none are as compelling as the authors might suggest. here are a few examples of techniques used. madagascar project takes your approach, inside the make script have the simulations run that produc... | https://api.stackexchange.com |
well, you said that you...... have a lot of trouble connecting the photo to the diagram. and that's quite excusable : interpreting that x - ray image is actually very complicated. all the quotes and images in this answer, except the bulleted list further down, come from this paper ( lucas, 2008 ), which explains that h... | https://api.stackexchange.com |
##ffraction pattern for a - dna along the first few layer lines, these suggest the crystalline order in the fibre. in the high - humidity b - dna pattern, these crystalline spots are absent, suggesting that the extra water molecules must have invaded the space between the dna molecules, freeing them from being locked i... | https://api.stackexchange.com |
from nitish shirish keskar, dheevatsa mudigere, jorge nocedal, mikhail smelyanskiy, ping tak peter tang. on large - batch training for deep learning : generalization gap and sharp minima. : the stochastic gradient descent method and its variants are algorithms of choice for many deep learning tasks. these methods opera... | https://api.stackexchange.com |
highly curved ) then the approximation will not be very good for very far, so only small step sizes are safe. you can read more about this in chapter 4 of the deep learning textbook, on numerical computation : when you put m examples in a minibatch, you need to do o ( m ) computation and use o ( m ) memory, but you red... | https://api.stackexchange.com |
that wiki page is abusing language by referring to this number as a probability. you are correct that it is not. it is actually a probability per foot. specifically, the value of 1. 5789 ( for a height of 6 feet ) implies that the probability of a height between, say, 5. 99 and 6. 01 feet is close to the following unit... | https://api.stackexchange.com |
} } \ exp ( - z ^ 2 / 2 ) dz = 0. 29544 \ d ( \ text { height } ) / 0. 18717 = 1. 5789 \ d ( \ text { height } ). $ $ ( actually, i cheated : i simply asked excel to compute normdist ( 6, 5. 855, 0. 18717, false ). but then i really did check it against the formula, just to be sure. ) when we strip the essential differ... | https://api.stackexchange.com |
turns out, simply keeping track of the next candidate line ( after sorting the sample line numbers ) fixes the performance issue, and most of the remaining slowness seems to be due to the overhead of actually reading the file so there ’ s not very much to improve. since i don ’ t know how how to do this in sed, and it ... | https://api.stackexchange.com |
if you have multi - line fasta files, as is very common, you can use these scripts1 to convert between fasta and tbl ( sequence _ name < tab > sequence ) format : fastatotbl #! / usr / bin / awk - f { if ( substr ( $ 1, 1, 1 ) = = " > " ) if ( nr > 1 ) printf " \ n % s \ t ", substr ( $ 0, 2, length ( $ 0 ) - 1 ) else ... | https://api.stackexchange.com |
##cgcatagctaacgatcgactagtgatgc atagagctagatcagctacgatagcatcgatcgactacgatcagcatcac this can be a very useful trick when searching a fasta file for a string : tbltofasta file. fa | grep'foo'| fastatotbl if you really want to keep the leading > of the header ( which doesn't seem very useful ), you could do something like ... | https://api.stackexchange.com |
what does this soft masking actually mean? a lot of the sequence in genomes are repetitive. human genome, for example, has ( at least ) two - third repetitive elements. [ 1 ]. these repetitive elements are soft - masked by converting the upper case letters to lower case. an important use - case of these soft - masked b... | https://api.stackexchange.com |
there is a very nice database, pdbcull ( also known as the pisces server in the literature ). it filters the pdb for high resolution and reduced sequence identity. it also seems to be updated regularly. depending on the cut - offs, you get between 3000 and 35000 structures. if you are specifically interested in rotamer... | https://api.stackexchange.com |
proper bypassing and grounding are unfortunately subjects that seem to be poorly taught and poorly understood. they are actually two separate issues. you are asking about the bypassing, but have also implicitly gotten into grounding. for most signal problems, and this case is no exception, it helps to consider them bot... | https://api.stackexchange.com |
everything else is considered relative to the ground net. however, think what happens as you run current thru the ground net. it's resistance isn't zero, so that causes a small voltage difference between different points of the ground. the dc resistance of a copper plane on a pcb is usually low enough so that this is n... | https://api.stackexchange.com |
nets can be a star or whatever right under the microcontroller and still allow other signals to be routed around them as required. however, once again, these local nets must have exactly one connection to the main board power and ground nets. if you have a board level ground plane, then there will be one via some place... | https://api.stackexchange.com |
piece of sheet metal soldered over the nasty section at production time. he thought that just by enclosing everything in metal that it wouldn't radiate. that's wrong, but somewhat of a aside i'm not going to get into now. the can did reduce emissions so that they just squeaked by fcc testing with 1 / 2 db to spare ( th... | https://api.stackexchange.com |
i just received a reply from 1000genomes regarding this. i'll post it in its entirety below : looking at the example you mention, i find it difficult to come up with an interpretation of the information whereby the stated end seems to be correct, so believe that this may indeed be an error. since the v4. 0 was created,... | https://api.stackexchange.com |
this is a very good question. einstein himself, in a 1907 review ( available in translation as am. j. phys. 45, 512 ( 1977 ), e. g. here ), and planck, one year later, assumed the first and second law of thermodynamics to be covariant, and derived from that the following transformation rule for the temperature : $ $ t'... | https://api.stackexchange.com |
there are both biological and social factor for that : biological females have two x chromosomes. when mutations in genes of the x chromosome occur, females have a second x to compensate. males, on the other hand gave just one chromosome x and all genes its genes express themselves, even those lethal or deleterious. fe... | https://api.stackexchange.com |
both sift and surf authors require license fees for usage of their original algorithms. i have done some research about the situation and here are the possible alternatives : keypoint detector : harris corner detector harris - laplace - scale - invariant version of harris detector ( an affine invariant version also exi... | https://api.stackexchange.com |
you have to subclass the rv _ continuous class in scipy. stats import scipy. stats as st class my _ pdf ( st. rv _ continuous ) : def _ pdf ( self, x ) : return 3 * x * * 2 # normalized over its range, in this case [ 0, 1 ] my _ cv = my _ pdf ( a = 0, b = 1, name ='my _ pdf') now my _ cv is a continuous random variable... | https://api.stackexchange.com |
i think linear predictive coding ( otherwise known as an auto - regressive moving average ) is what you are looking for. lpc extrapolates a time series by first fitting a linear model to the time series, in which each sample is assumed to be a linear combination of previous samples. after fitting this model to the exis... | https://api.stackexchange.com |
a, zeros ( 1, p - m ), zf ) ; here is the output : it does a reasonable job, though the prediction dies off with time for some reason. i don't actually know much about ar models and would also be curious to learn more. - - edit : @ china and @ emre are right, the burg method appears to work much better than lpc. simply... | https://api.stackexchange.com |
there's a flaw in jason r's answer, which is discussed in knuth's " art of computer programming " vol. 2. the problem comes if you have a standard deviation which is a small fraction of the mean : the calculation of e ( x ^ 2 ) - ( e ( x ) ^ 2 ) suffers from severe sensitivity to floating point rounding errors. you can... | https://api.stackexchange.com |
##1 = sum ( x ) n = len ( x ) s2 = sum ( [ x _ i * * 2 for x _ i in x ] ) return {'mean': s1 / n,'variance': ( s2 / n - ( s1 / n ) * * 2 ) } x1 = [ 1, - 1, 2, 3, 0, 4. 02, 5 ] x2 = [ x + 1e9 for x in x1 ] print " naive _ stats : " print naive _ stats ( x1 ) print naive _ stats ( x2 ) print " stats : " print stats ( x1 ... | https://api.stackexchange.com |
i don't think that's really true anymore. some fortran use is historical ( i. e., early codes were developed in fortran because that was the best programming language for number crunching in the 70s and 80s ). heck, the name stands for " formula translation. " some fortran use is because of performance. the language wa... | https://api.stackexchange.com |
there are about 100 ( purves, 2001 ) to 400 ( zozulya et al., 2001 ) functional olfactory receptors in man. while the total tally of olfactory receptor genes exceeds 1000, more than half of them are inactive pseudogenes. the combined activity of the expressed functional receptors accounts for the number of distinct odo... | https://api.stackexchange.com |
it just means that you can create levels or puzzles within these games that encode np - hard problems. you can take a graph coloring problem, create an associated super mario bros. level, and that level is beatable if and only if the graph is 3 - colorable. if you want to see the specific way the np - complete problems... | https://api.stackexchange.com |
in programming language design and implementation, there is a large number of choices that can affect performance. i'll only mention a few. every language ultimately has to be run by executing machine code. a " compiled " language such as c + + is parsed, decoded, and translated to machine code only once, at compile - ... | https://api.stackexchange.com |
the programmer than in c, where that would cause undefined behavior, meaning that the program might crash, overwrite some random data in memory, or even perform absolutely anything else ( the iso c standard poses no limits whatsoever ). however, keep in mind that, when evaluating a language, performance is not everythi... | https://api.stackexchange.com |
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