similar to: Slope of surface

Displaying 20 results from an estimated 10000 matches similar to: "Slope of surface"

2006 Jan 28
3
Creating 3D Gaussian Plot
Hello, I requested help a couple of weeks ago creating a dipole field in R but receieved no responses. Eventually I opted to create a 3d sinusoidal plot and concatenate this with its inverse as a means for a "next best" situation. It seems that this isn't sufficient for my needs and I'm really after creating a continuous 3d gaussian mesh with a "positive" and
2004 Sep 07
6
Further png() question
Ok, I have reinstalled R-1.9.0 and this appears to have fixed the problems I was having with png(). However, I have a further question regarding png() Is it possible to pass a par() argument to the png() command? I am wanting to produce 4 plots per object, which I normally acheive on an X window by par(mfrow=c(1,4)). I have tried calling a new plot and setting par in this way but this has no
2005 Feb 16
4
Passing colnames to graphics title
Hi, Just a quick query - if I'm creating a function to produce a number of histograms per page of output (one per column from a matrix), how can I pass the column name of the matrix into the title (or indeed to form part of the x-axis label)? TIA, Laura Laura Quinn Institute of Atmospheric Science School of Earth and Environment University of Leeds Leeds LS2 9JT tel: +44 113 343 1596 fax:
2004 Aug 15
3
Stacking Vectors/Dataframes
Hello, Is there a simple way of stacking/merging two dataframes in R? I want to stack them piece-wise, not simply add one whole dataframe to the bottom of the other. I want to create as follows: x.frame: aX1 bX1 cX1 ... zX1 aX2 bX2 cX2 ... zX2 ... ... ... ... ... aX99 bX99 cX99 ... zX99 y.frame: aY1 bY1 cY1 ... zY1 aY2 bY2 cY2 ... zY2 ... ... ... ... ... aY99 bY99 cY99 ...
2006 Feb 08
2
slightly off-topic re prcomp()
Hi, I was wondering if anyone could tell me why prcomp() will "Invent" modes of variation in a PCA on identical replicates of data? I would have expected 50 (or whatever number) of identical replicates to return a null score in such an analysis (or at the least, all variables would share the same PC score). This is not the case and I was wondering could someone point me in the direction
2005 Feb 02
2
Runnning R remotely
Hi, I was wondering if anyone might be able to help. I am trying to run R on a remote machine, part of the model run I am attempting writes an external file output as a png (about 48 iterations per model run). I am running R 1.9.1 on SuSe9.0, and am accessing this via ssh from a Debian machine. Initially I used the command ssh -X IP.address and whilst I was able to run the model successfully the
2006 Jan 22
3
White Noise
I'm wanting to create a series of near-identical matrices via the addition of "white noise" to my starting matrix. Is there a function within R which will allow me to do this? Thank you Laura Quinn Institute of Atmospheric Science School of Earth and Environment University of Leeds Leeds LS2 9JT tel: +44 113 343 1596 fax: +44 113 343 6716 mail: laura at env.leeds.ac.uk
2005 Mar 01
3
Reconstructing Datasets
Hi, Is it possible to recreate "smoothed" data sets in R, by performing a PCA and then reconstructing a data set from say the first 2/3 EOFs? I've had a look in the help pages and don't seem to find anything relevant. Thanks in advance, Laura Laura Quinn Institute of Atmospheric Science School of Earth and Environment University of Leeds Leeds LS2 9JT tel: +44 113 343 1596
2005 May 16
2
Fitting Contour to Data Points
Apologies for the mass mailing today! I am attempting to produce a contour plot for phsical data on a map matrix. I have a small number of data points which each has an (x,y) co-ordinate together with a corresponding value which I would like to cvreate a contour plot for. I have tried the following code: contour(data$x,data$y,data$value) but am told: Error in contour.default(data$x, data$y,
2004 Nov 14
2
Exporting to file: passing source name to file name in loop
Hi, I'm having a mental block as to how I can automatically assign filenames to the output of the following code. I am wishing to create a separate .png file for every image created, each of them having a sequential filename ie "sourcefile_index.png" so that I can create a movie from them. Please could someone tell me where I am going wrong? the following code works fine and
2006 Feb 20
1
Further rgl()/spheres3d() query
Hi, I am applying the following code to map pca loadings onto a 3d grid, my problem is this - the output only plots the spheres in the requested color (in this case "red") for the first argument. The sphere from the second argument appear as flat dark circles. Also the text3d() command only seems to work for a couple of the positions, with no text added in most cases. Could anyone offer
2005 May 16
3
Mental Block with PCA of multivariate time series!
Please could someone point me in the right direction as I appear to be having a total mental block with fairly basic PCA problem! I have a large dataframe where rows represent independent observations and columns are variables. I am wanting to perform PCA sequentially on blocks of nrows at a time and produce a graphical output of the loadings for the first 2 EOFs for each variable. I'm sure
2004 Sep 12
2
boxplot() from list
I have a list containing 48 objects (each with 30 rows and 4 columns, all numeric), and wish to produce 4 boxplot series (with 48 plots in each) , one for each column of each object. Basically I want a boxplot from boxplot(mylist[[]][,i]) for i in 1:4. It seems that I can create a boxplot of length 48 from the entire list, but I don't seem able to subscript to return 4 boxplots from the list
2004 Sep 06
1
Applying function to lots of separate data sets
I have a total mental block and can't find my way around this seemingly simple problem: I have created a function such that: my_answer_1=myfuntion(my_input_1) I am wanting to perform this calculation over a large number of datasets, but am having real difficulty calling and assigning - i think the problem les in the fact that I need to paste for call and assign. this is my best attempt so
2007 Feb 08
1
Point estimate from loess contour plot
Hi, I was wondering if anyone knows of a way by which one can estimate values from a contour plot created by using the loess function? I am hoping to use the loess contour plot as a means of interpolation to identify the loess created values at points at pre-defined (x,y) locations. Could anyone point me in the right direction please? Thanks. Laura Quinn Institute of Atmospheric Science School
2004 Oct 06
4
Performing Analysis on Subset of External data
Hi, I want to perform some analysis on subsets of huge data files. There are 20 of the files and I want to select the same subsets of each one (each subset is a chunk of 1500 or so consecutive rows from several million). To save time and processing power is there a method to tell R to *only* read in these rows, rather than reading in the entire dataset then selecting subsets and deleting the
2006 Feb 13
1
Saving surface3d Output
Hello, Please could someone advise if it's possible to save the graphical output from the surface3d() function? I have tried the dev.copy() function to save as a pdf but an error message says I cannot copy from the null device. Laura Quinn Institute of Atmospheric Science School of Earth and Environment University of Leeds Leeds LS2 9JT tel: +44 113 343 1596 fax: +44 113 343 6716 mail:
2003 Nov 07
2
Non-standard axis plotting
I am trying to plot positions on a grid where the x and y axis equate to longitudinal and latitudinal co-prdinates respectively. As these co-ordinates are southings and westings, i need the origin of my graph to contain the two highest values of each co0ordinate, with the values decreasing in both respects along both axes - I cannot seem to find any function within r to allow me to do this. Also,
2003 Oct 07
4
Beginner's query - segmentation fault
I am dealing with a huge matrix in R (20 columns, 54000 rows) and have lots of missing values within the dataset which are currently displayed as the value "-999.00" I am trying to create a new matrix (or change the existing one) to display these values as "NA" so that I can then perform the necessary analysis on the columns within the matrix. The matrix name is temp and the
2004 Jun 24
0
Problem with predict arima
I have fitted an arima(0,0,2) model to my data, and am trying to plot a forecast for the next 15 time steps, but each time i try I am given the following error message: Error in .cbind.ts(list(...), makeNames(...), dframe = dframe, union = TRUE) : non-time series not of the correct length I am calculating as follows: my.arima<-arima(my.list,order=c(0,0,2))