Checking on over-sampling of data with our box methods

Idea -- > Try to get a feel for how over- or under-sampled our data is for different box sizes, numbers of boxes, and in different fields. It is important to understand how adjusting these parameters changes the sampling of the data. The ranges are varied from a Half-Box Width of 10 up to 60, which correspond to Box Widths from 30" to 175". The number of boxes is varied from 25 to 200 in steps of 25. We use fields 3, 4, 7, and Sub, with and without our masks (hand masks + u>25 mask + sextracted/monte-carlo mask).

Code Outline: clicking on the links will take you to that section of the code - it's online, too, on a separate page.

Code --> PNeNstat.sm    PNeNstat   -   preps colours, variables, running parameters, loops and calls PNew (always), PNeNdat, PNemax, PNeD, PNeG (all sometimes)
                                        PNeNdat   -   runs 3 box programs - 1+ PNe, 0 PNe, random
                                        PNew        -   reads in .fits info and loads PNe RA/DEC data
                                        PNe1        -    finds coordinates of random boxes with at least 1 PNe in them [by the same method as given on PNe8 page]
                                                              saves to a file 8.100.Im3.fits.R10.wfound.dat [with 100 boxes, image 3.fits, range 10, w = 1+ PNe found] the RA/DEC of boxes
                                        PNe0        -    finds coordinates of random boxes with NO PNe in them
                                                              saves to a file 8.100.Im3.fits.R10.0found.dat the RA/DEC of all boxes
                                        PNer        -    finds coordinates of random boxes without stipulation on # PNe
                                                              saves to a file 8.100.Im3.fits.R10.Rfound.dat the RA/DEC of boxes
                                        PNePG    -    small program that prepares graphing stuff
                                                              sets device, sets overall limits, draws all axes/labels
                                        PNeD      -     reads back in the positional .dat files from above and computes # pixels counted more than once
                                                              calls PNePG to prep graphs
                                                              for each box selection method: 1+PNe, 0PNe, random: [links below are examples for 1+PNe method, others are very similar]
                                                                  reads in .dat file
                                                                  sets up 'image' (2D matrix) same size as image to store # times counted as each pixel value
                                                                  loops over all boxes, adds 1 to pixels inside each box
                                                                  loops over all pixels, adds 1 to counter if a pixel has value > 1
                                                                  writes to file 8.100.Im3.fits.R10.wfound.N.fits the 'image' array in case we need to look at it again
                                                                  divides # pixels counted more than once by max pixels possible (from PNemax programs) to get fraction
                                                                  plots on appropriate window of plot this fraction
                                                              after 1+ PNe, 0 PNe, random are done, writes all fractions out to file: 8.N.Im3.fits.R10.found.N.dat
                                        PNeG      -     program to JUST graph data if all .dat files have already been generated and can just be re-read
                                        PNemaxread-program to read in max values if they've already been calculated and stored in *.max files
                                        PNemax   -    runs the max finding programs, listed below, and writes out .max file after they've finished
                                        PNe1max  -   loops over all pixels, on each one, checks if it is within 2*rang+1 of a PNe AND unmasked, if so, adds to counter
                                        PNe0max  -   loops over all pixels, on each one, checks if it is farther than rang+1 of a PNe AND unmasked, if so adds to counter
                                        PNeRmax  -  finds total number of unmasked pixels


Results

NOTE: at this time (6/13/06 @ 2 pm) the 0 PNe graphs are not properly normalised for each range... the shapes are correct, but the amplitude of each curve is wrong relative to the other curves and to the scale on the axis. The problem has been corrected and the graphs will be remade and uploaded in a day or two.
     


     


7.fits      7m.fits


Sub.fits      Subm.fits





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