search for: janoska

Displaying 6 results from an estimated 6 matches for "janoska".

2011 Feb 25
5
Substituting inside expression
I am having following problem: I?m constructing model for calculation of area of triangle. I know sides a, b, and gamma angle. I wish to calculate the area using heron?s formula: S <- sqrt(s*(s-a)*(s-b)*(s-c)) where s <- (a+b+c)/2 and c is calculated using law of cosines: c <- sqrt(a^2 + b^2 -2*a*b*cos(gamma)) since i am calculating a regression model, i need derivation of this
2010 Sep 03
1
How to use lm() output for systemfit() 'Seemingly unrelated regression'
...e the problem is. The problem remains even when I try: > fo1 <- r98[,2] ~ f98[,1] + f98[,2] + ... + f98[,43] > fo2 <- r98[,1] ~ f98[,1] + f98[,2] + ... + f98[,43] instead of using lm() Could someone give me a hand? I am quite new to R, so possibly the solutions is simple:) Thanks Zbynek Janoska -- View this message in context: http://r.789695.n4.nabble.com/How-to-use-lm-output-for-systemfit-Seemingly-unrelated-regression-tp2525418p2525418.html Sent from the R help mailing list archive at Nabble.com.
2010 Dec 16
2
How can I draw a line in empirical distribution function?
I've got the graphic with this: a=c(120,40,75,85,55,75,55,90,90,55,155) plot(ecdf(a)) How can I draw lines to show the lower quatile and upper quartil? I only know there is the argument lines(), but I don't know how to use it -- View this message in context: http://r.789695.n4.nabble.com/How-can-I-draw-a-line-in-empirical-distribution-function-tp3090675p3090675.html Sent from the R
2011 Feb 28
3
Incorrectness of mean()
I have found following problem: I have a vector: > a <- c(1.04,1.04,1.05,1.04,1.04) I want a mean of this vector: > mean(a) [1] 1.042 which is correct, but: > mean(1.04,1.04,1.05,1.04,1.04) [1] 1.04 gives an incorrect value. how is this possible? thanks, zbynek -- View this message in context: http://r.789695.n4.nabble.com/Incorrectness-of-mean-tp3327701p3327701.html Sent from the R
2010 Dec 20
2
How to optimize function parameters?
Hi, I have a dataset and I want to fit a function to it. The function is variogram model (http://en.wikipedia.org/wiki/Variogram) The variogram model is defined by three parameters and I want them to be automatically optimized for real time data. I tried to use gafit {gafit} for this, but there are some data configuration, where optimal results given by gafit() are negative, which is not correct
2011 Mar 25
0
applying random functions to multisets
Hi, I am solving following problem: Suppose I have some multiset: > multiset <- c("a","a","c","d","d") and rules, which operate with it (for simplicity not writen in R functions) > rule1: "a" -> c("a","b") > rule2: "a" -> c("a","c") > rule3: "c" ->