Procedure: bin2d Purpose: A slightly simpler wrapper for vassilis's routine for 2-d binning NOTE: despite the fact that they are keywords either binsize or binnum must be set for the proceedure to function Inputs: x: the x components for the bins. Should be an N length array. y: the y components for the bins. Should be an N length array. arrs2bin: the arrays to be binned should be an NxM sized array or an N sized array (Note: Interpolation to match the N component of input arrays is the responsibility of the user.) Keywords: binsize: a number or a 2 element array. If a single number it will be treated as size of the bins for the x dimension and the y dimension. If it is a two element array, the first element will be the size of the bins on the x axis and the second element will be the size of the bins on the y axis. Warning: Either Binsize or binum must always be set. binum: a number of 2 element array. If a single number it will be treated as the number of bins on for both axes. If a 2 element array, the first element is number of bins on the x-axis and the second element is the number of bins on the y-axis. (Note: The number of bins actually produced may vary by +- 1) Bins will be evenly spaced over xrange and yrange if provided, and over the range of the data if not. Warning: Either Binsize or binum must always be set. xrange,yrange(optional): a 2 element array specifying the min and the max over which binning will occur for the respective axis(default: all data) flagnodata(optional): set this keyword to a flag to replace output values with if there is no data. (default: 0) averages(output): outputs 2-d array in which the bin averages are stored medians(output): outputs 2-d array in which the bin medians are stored stdevs(output): outputs 2-d array in which the bin stdevs are stored. binhistogram(output): a 2-d histogram of the number of elements used for constructing each cell xcenters,ycenters(output): 1-d array of the centers for the bins on each axis. minvarvec,maxvarvec(output): Either of these are set arrs2bin will must have dimension M >= 2. The first 2 arrays of the M dimension(ie arrs2bin[*,0] and arrs2bin[*,1] will be treated as corresponding elements of an X,Y flow field. The maxvariance direction will be a 2D vector in maxvarvec for each cell. The minvariance direction will be a 2D vector in minvarvec for each cell. The vector norm is the variance in the max/min direction, i.e., lambda_i=sqrt(maxvarvec(*,0)^2+maxvarvec(*,1)^2). Notes and Warnings: 1. Interpolation to match the N component of input arrays is the responsibility of the user. 2. The number of bins actually produced may vary by +- 1 from the number requested by binum 3. Either binsize or binum must always be set. 4. If both binsize and binum, binsize will take precedent. SEE ALSO: bin1d.pro,plotxyz.pro,thm_crib_plotxyz.pro $LastChangedBy: pcruce $ $LastChangedDate: 2008-02-06 13:43:58 -0800 (Wed, 06 Feb 2008) $ $LastChangedRevision: 2352 $ $URL: svn+ssh://thmsvn@ambrosia.ssl.berkeley.edu/repos/ssl_general/trunk/tplot/tplotxy.pro $