similar to: Function to find angle between coordinates?

Dear R-help, There seems to be a web page I am unable to download using RCurl. I don't understand why it won't download: > library(RCurl) > my.url <- "http://www.nytimes.com/2009/01/07/technology/business-computing/07program.html?_r=2" > getURL(my.url) [1] "" Other web pages are ok to download but this is the first time I have been unable to download a

Dear all, Lets say I have a data frame as follows: > Date <- as.Date(c('2006-08-23', '2006-08-30', '2006-09-06', '2006-09-13', '2006-09-20')) > Income <- c(73.79, 72.46, 76.32, 72.43, 72.62) > data.frame(Date, Income) Date Income 1 2006-08-23 73.79 2 2006-08-30 72.46 3 2006-09-06 76.32 4 2006-09-13 72.43 5 2006-09-20 72.62 >

Assuming your polyline is defined by two vectors, one for the x coordinates, one for the y coordinates, you can try the following library(NISTunits) polyangles <- function(xV,yV) { stopifnot( (length(xV)==length(yV)) && (length(xV) >= 3)) v <- function(i) { c( xV[i]-xV[i-1], yV[i]-yV[i-1])} vlen <- function(v) { sqrt(sum(v*v)) } lV <- rep(NA_real_,length(xV)) for

Dear R users I am trying to find a formula to calculate the angle of a polyline. Is there a way to do this? Many thanks. -- Best Regards Javad Bayat M.Sc. Environment Engineering Alternative Mail: bayat194 at yahoo.com [[alternative HTML version deleted]]

A polyline by definition has many angles, so your question is ill-formed. And this is a question about math, not R, so is off topic here. I suggest reading Wikipedia. -- Sent from my phone. Please excuse my brevity. On January 29, 2018 11:10:02 PM PST, javad bayat <j.bayat194 at gmail.com> wrote: >Dear R users >I am trying to find a formula to calculate the angle of a polyline. Is

I like to use complex numbers for 2-dimensional geometry. E.g., > polyAngles2 function (xV, yV) { stopifnot((length(xV) == length(yV)) && (length(xV) >= 3)) z <- complex(re = xV, im = yV) c(NA, diff(Arg(diff(z))), NA) # radians, positive is counter-clockwise } > x <- c(0:3) > y <- c(0,0,1,1) > polyAngles2(x,y) / pi * 180 [1] NA 45 -45 NA Bill

Dear all, If I have the following data frame: > set.seed(21) > df1 <- data.frame(col1=c(rep('a',5), rep('b',5), rep('c',5)), col4=rnorm(1:15)) col1 col4 1 a 0.793013171 2 a 0.522251264 3 a 1.746222241 4 a -1.271336123 5 a 2.197389533 6 b 0.433130777 7 b -1.570199630 8 b -0.934905667 9 b 0.063493345 10 b

Dear R-help, Please forgive me if any of the following sounds naieve/confused, i've just got back from a mini-pub-crawl, slightly tipsy, and am feeling brave to ask a possibly silly question... also, not to shiny on the technical side of things. Problem - I need to text mine a collection of 10,000 plain text documents, all of which are sitting in a single folder. i don't have any money

Dear all: I'm enjoying using rgl and I want to set a specific viewpoint. I understand that view3d() will do so by setting the 3d polar coordinate angles, theta and phi. In standard polar coordinates, theta is the angle away from the X axis in the X-Y plane and phi (inclination angle) is the angle between the Z axis and the radius vector It appears that when you use view3d() theta is

Dear all, I've got a problem with the function atan2. For a couple of coordinates x and y, This function returns the angle between the vector of coordinates (x, y) and the abscissa axis, i.e. it is the same as atan(y/x) (as indicated on the help page). If we consider the vector with coordinates x = 0 and y = 0, we have the following result: > atan(0/0) [1] NaN This is expected.

Is there packaged code to convert geographical coordinates (e.g., longitude, latitude, elevation) to Cartesian coordinates in 3-space? I can see how to do this using 1. a spherical-to-Cartesian conversion like pracma::sph2cart(tpr) http://cran.r-project.org/web/packages/pracma/ 2. a geographical-to-spherical conversion. This seems to involve (in roughly increasing order of difficulty or

Hi, I try to calculate the angle between two first eigenvectors of different covariance matrices of biological phenotypic traits for different populations. My issue here is, that all possibilities to do so seem to normalize the eigenvectors to length 1. Although the helpfile of eigen() states, that using eigen(, symmetric = FALSE, EISPACK =TRUE) skips normalization this is (I guess) not applicable

Thanks a lot for the reply.After ?looking at different parts of the code today I was able to start with simple 2D polar plots as the attached pdf file. ?In case the attachment is not visible I used the plot.polar function to create something like that.https://vijaybarve.files.wordpress.com/2013/04/polarplot-05.png Now the idea now will be to put three of those (for X,Y,Z) in a 3d rotatable plane.

Hi, I'd like to plot in in polar coordinates a line which is given as a vector of lengths and angles. library("plotrix")

On 21/06/2017 5:23 AM, Alaios via R-help wrote: > Thanks a lot for the reply.After looking at different parts of the code today I was able to start with simple 2D polar plots as the attached pdf file. In case the attachment is not visible I used the plot.polar function to create something like that.https://vijaybarve.files.wordpress.com/2013/04/polarplot-05.png > Now the idea now will be

Thanks Duncan for the replyI can not suppress anything these are radiation pattern measurements that are typically are taken at X,Y and Z planes. See an example here, where I want to plot the measurements for the red, green and blue planes (so the image below withouth the 3d green structure inside)https://www.researchgate.net/publication/258391165/figure/fig7/AS:322947316240401 at

Dear all, I'd like to produce a simple pie chart for a customer (I know it's bad but they insist), and I have some difficulties setting the initial angle. For example: pie(c(60, 40), init.angle=14) and pie(c(80, 20), init.angle=338) both present the slices in the same direction, where: pie(c(60, 40)) pie(c(80, 20)) present the slices in different directions. I read everything I

Tena koe Simon plot(1:10, 1:10, type='n') polygon(c(2,3,6,8), c(2,5,5,3), density=20, angle=90) polygon(c(2,3,6,8), 5+c(2,5,5,3), density=20, angle=0) I don't understand your problem. Perhaps if you "provide[d] commented, minimal, self-contained, reproducible code" it would help. HTH .... Peter Alspach -----Original Message----- From: R-help [mailto:r-help-bounces at

Filling polygons with lines is a throwback to the time when the height of quality graphics was the mechanical pen plotter (a device that used a pen in a mechanical arm to draw the plot on a piece of paper). Computing and printing technology has advanced quite a bit from that day, so you may want to reconsider why you want polygons filled with lines instead of just a solid color (and I consider

When legend() is used with the angle argument as follows, not only the boxes beside the legend text, but also the whole legend box is filled with shading lines. I think this is not intended: plot(1:10) legend(8, 4, c("A", "B"), angle=c(10, 80), fill=NULL, density=20) I'd suggest as a fix (legend.R of R-1.5.0): 25c25 < rect2 <- function(left, top, dx, dy,