search for: pedagogical

Hi I am currently (for pedagogical purposes) writing a simple numerical analysis library in R. I have come unstuck when writing a simple Newton-Raphson implementation, that looks like this: f <- function(x) { 2*cos(x)^2 + 3*sin(x) + 0.5 } root <- newton(f, tol=0.0001, N=20, a=1) My issue is calculating the symbolic deriva...

...starting with a brute-force approach and refining progressively. http://jostamon.blogspot.com/2009/02/goldbachs-comet.html I'd welcome your suggestions on improvements, alternatives, other optimisations, esp. to do with space vs time tradeoffs. Is this an example interesting enough for pedagogical purposes, do you think? Please advise. Cheers, MM [[alternative HTML version deleted]]

...this dataset as sugested Weiwei here: https://stat.ethz.ch/pipermail/r-help/2007-July/136627.html. I tried to adapt his recommendation but no succes. Can anyone help me? Regards, Iurie Malai, Senior Lecturer Department of Psychology Faculty of Psychology and Special Education Ion Creanga Moldova Pedagogical State University -------------- next part -------------- "esan" "reus" 1 9.3 1 9.05 1 7.78 1 7.11 1 7.14 1 8.12 1 7.5 1 7.84 1 7.8 1 7.52 1 8.84 1 6.98 1 6.1 1 6.89 1 6.5 1 7.5 1 7.8 1 5.5 1 6.61 1 7.65 1 7.68 1 7.65 1 8.37 1 5.38 1 7.89 1 7.59 1 6.31 1 7.79 1 6.01 1 7.41 1 7.56...

Dear all, I have written a small set of functions for drawing graphical representations of R objects and evaluations of R expressions. It is mainly intended for pedagogical purposes. Here are some samples: http://panini.u-paris10.fr/~sloiseau/sampleGraphics.pdf The idea is to use some graphical conventions in order to make clear the abstract syntax and to explain function, extraction, recycling, type conversion, properties of data structures, etc. I would be very i...

...; by(eval(parse(text=(paste("data",data.n[3],sep="$")))), data$groupFactor, shapiro.test) > } but not working and no errors. Why? Please help. -- Regards, Iurie Malai, Senior Lecturer Department of Psychology Faculty of Psychology and Special Education Ion Creanga Moldova Pedagogical State University - www.upsm.md http://en.wikipedia.org/wiki/Ion_Creang%C4%83_Pedagogical_State_University

For a pedagogical purpose, I was trying to show how the formula for a simple regression line (~1+x) could be crossed with a factor (~1:group + x:group) to fit separate regressions by group. For example: set.seed(201108) dat <- data.frame(x=1:15, y=1:15+rnorm(15), group = sample(c('A','B&...

...test with continuity correction data: X3 by X2 W = 439, p-value = 0.1291 alternative hypothesis: true location shift is not equal to 0 > I researched on this, but I can't find a solution. I would really appreciate any help. P.S. Excuse my lack of terminology :). Iurie Malai Moldova Pedagogical State University -- View this message in context: http://www.nabble.com/How-to-apply-the-Wilcoxon-test-to-a-hole-table-at-once--tp26030572p26030572.html Sent from the R help mailing list archive at Nabble.com.

Howdy All, I''ve a bit of a strange problem here. I have a filesystem with one snapshot that simply refuses to be destroyed. The snapshots just prior to it and just after it were destroyed without problem. While running the zfs destroy command on this particular snapshot, the server becomes more-or-less hung. It''s pingable but will not open a new shell (local or via ssh) however

..., lwd=2) Now I would like to add yet another trend line, but this time a quadratic one. So I have two trend lines. One linear trend line and a quadratic trend line. A trend line as if I had taken I(income^2) into the equation. I know I can make two models and compare them using anova, but for pedagogical resons I wold like to visualise it. I know the trick from my past as an SPSS user, but I would like to do this in R as well. Se it in SPSS http://www.childrens-mercy.org/stats/weblog2006/QuadraticRegression.asp Thanks in adcance Eric

Hi, Is there a simple way of rolling back to a specific TXG of a volume to recover from such a situation? Many thanks, Przem -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://mail.opensolaris.org/pipermail/zfs-discuss/attachments/20110627/9b1c5a85/attachment.html>

...or data analysis and graphics (alas not cited in the approved manner): http://labs.google.com/papers/disk_failures.pdf Perhaps some of the eminences grises of the R Foundation could prevail upon Google to make some the data reported in the paper available for inclusion in an R library or two, for pedagogical purposes? Tim C

....test(Dataset$age, Dataset$sex) Levene's Test for Homogeneity of Variance Df F value Pr(>F) group 1 0.8739 0.3567 33 I am not sure what means "Pr(>F)"? Can anyone explain/translate this? Regards, Iurie Malai Department of Psychology and Special Education Moldova Pedagogical State University iurie.malai@gmail.com [[alternative HTML version deleted]]

How to make a launcher for Rattle? Regards, Iurie Malai Moldova Pedagogical State University [[alternative HTML version deleted]]

Hi all We have a 100kVA GE LP Series UPS. I can't find this series in the HCL, but other GE UPSes are listed. Would it be possible to somehow use NUT with this UPS? -- Vennlige hilsener / Best regards roy -- Roy Sigurd Karlsbakk (+47) 98013356 roy at karlsbakk.net http://blogg.karlsbakk.net/ GPG Public key: http://karlsbakk.net/roysigurdkarlsbakk.pubkey.txt -- I all pedagogikk er det

Hi all I have installed a new server with 77 2TB drives in 11 7-drive RAIDz2 VDEVs, all on WD Black drives. Now, it seems two of these drives were bad, one of them had a bunch of errors, the other was very slow. After zfs offlining these and then zfs replacing them with online spares, resilver ended and I thought it''d be ok. Appearently not. Albeit the resilver succeeds, the pool status

Hi all Trying to setup dovecot with mysql and postfix, I have configured it as given below. thecot user has the dovecot group as primary, and is also a member of mail and dovecot-users. Still, it can't setgid to dovecot-users. I tried changing the shell for the dovecot user to something useful and chmod'ing a file to dovecot-users, and it work well. Still, no mail comes through

Hi all Has anyone done any testing with dedup with OI? On opensolaris there is a nifty "feature" that allows the system to hang for hours or days if attempting to delete a dataset on a deduped pool. This is said to be fixed, but I haven''t seen that myself, so I''m just wondering... I''ll get a 10TB test box released for testing OI in a few weeks, but before

The public connection API is defined in https://github.com/wch/r-source/blob/trunk/src/include/R_ext/Connections.h I'm not sure of a good pedagogic example; people who want to write their own connections usually want to do so for complicated reasons! This is my own abandoned attempt

...use the grplasso package on a data set where I want to fit a linear model.? My interest is in identifying significant?beta coefficients.? The documentation is a bit cryptic so I'd appreciate some help. ? I know this is a strategy for large numbers of variables but consider a simple case for pedagogical puposes.? Say I have?two 3 category predictors (2 dummies each), a binary predictor and a continuous predictor with a continuous outcome: ? y? x1? x2? x3? x4 x5 x6 rows of data here ...... ...... ? Naturally, I want to select x1 and x2 as a group and x3 and x4 as another group.? The documentation...

Hi I''m running OpenSolaris 148 on a few boxes, and newer boxes are getting installed as we speak. What would you suggest for a good SLOG device? It seems some new PCI-E-based ones are hitting the market, but will those require special drivers? Cost is obviously alsoo an issue here.... Vennlige hilsener / Best regards roy -- Roy Sigurd Karlsbakk (+47) 97542685 roy at karlsbakk.net