search for: geochemistri

I'm in e-mail contact with a geochemist who maintains a well regarded geochemistry web site. He's drawing diagrams either with a Turbo Pascal program running in a DOS window or with Excel. I'm trying to persuade him that R would be a better choice. Something he's particularly keen on is ternary diagrams. I think he is talking about ternary phase diagrams, and if so, it looks as

Fellow R users, I'm using the BCE {BCE} function to run a Bayesian sediment mixing model. The aim is to find the optimum % contribution from each of the 4 source areas that can yield the target geochemistry. I have geochemistry for 4 source areas called Rat: Rat<-read.table(text="CaO MgO Na2O Al2O3 Topsoils 2.511250 0.7445500 0.7085500 14.10375 ChannelBanks

I have some data (REE plots - geochemistry) where I have values 1:14 for the x axis, but have no data for some x values. Here for example, let's say that I don't have data for x=2,5,8. So x<-1:14 y<-c(4, NA, 5, 9, NA, 3.4, 8, NA, 19, 22, 12, 14, 15.3, 15) if I plot the data plot(x,y) and then I want to join with lines lines(x,y) How do I get it so the points join across the

I've recently come across the following results reported from the lm() function when applied to a particular type of admittedly difficult data. When working with small data sets (for instance 3 points) with the same response for different predicting variable, the resulting slope estimate is a reasonable approximation of the expected 0.0, but the p-value of that slope estimate is a surprising

Hi, First checking out http://www.openbsd.org/errata.html Following is output and error from trying to compile the latest openssh on SGI IRIX (using cc). Previous versions of openssh have compiled cleanly on this system using the following configure options. Is there a quick fix for this? Cheers, Lachlan. ------------------------------------------------------- For SGI IRIX 6.5x 10151453

Hello all, I am a mac user running Wine to run geochemistry program on my mac under OS X 10.5.8 using Wine 1.1.35. I've got two out of my three programs up and running without a problem! When I try to run PhreePlot I get the following error in the wine command prompt: ***Error: Invalid PhreePlot system path. Check that the PhreePlot environment variable is specifying a valid directory

Tim, I think what you're seeing is https://en.wikipedia.org/wiki/Loss_of_significance. Cheers, Mark From: "Glover, Tim" <Tim.Glover at amecfw.com> To: "r-help at r-project.org" <r-help at r-project.org> Date: 09/05/2017 11:37 AM Subject: [R] Interesting behavior of lm() with small, problematic data sets Sent by: "R-help"

Dear Rich, It depends how the data is generated. Although I am not an expert in ecology, I can explain it based on a biomedical example. Certain variables are generated geometrically (exponentially), e.g. MIC or Titer. MIC = Minimum Inhibitory Concentration for bacterial resistance Titer = dilution which still has an effect, e.g. serially diluting blood samples; Obviously, diluting the

Hi, I am trying to create what are called "spider diagrams" in the geochemical literature using R. A spider diagram is basically a plot of the atomic number versus the concentration on a log scale. Lines are drawn from each atomic number for each sample. Right now, my data frame looks like: SAMPLE SITE V3 LA.NASC LAATNUM CE.NASC CEATMNUM 1 1A:001

Hi All I have a vector of about 15 million numbers which I would like to plot. The goal is the see the distribution. I tired the usual steps. 1. Histogram : never gets complete my window freezes w/out log base 10 2. Density : I first calculated the kernel density and then plotted it which worked. It would be nice to superimpose histogram with density but as of now I am not able to get this