Institut für Astronomie und AstrophysikAbteilung AstronomieSand 1, D-72076 Tübingen, Germany |
Array: the array that was WHERE'd Indices: the indices returned by WHERE
Col: Indices to first dimension. Row: Indices to second dimension. Frame: Indices to third dimension. Returned only for 3-d array.
If Array is not a vector or matrix, all return values are set to zero and a message is written to the screen.
1998 Sept 15 J.L.Saba Developed based on code from David Fanning's web site.
cygx1_rmsflux
calculate the rms variability sigma and the mean flux of 1s-lightcurve segments, bin sigma as a function of segment flux and fit a linear function (according to Uttley, Ph. and McHardy, I.M., MNRAS 2001, 323, L26-L30)
rmsflux.pro can conveniently be called by allrmsflux. When binning sigma as a function of segment flux, each bin has to contain at least n_val measurements to ensure an accurate estimate of the standard error in the mean sigma. The linear fit has the form y=k*x+a (sigma=k*flux+a), so the fit results are slope k and offset a.
timing tools
id : string containing the observation (e.g.'28.all.14off') obspath : string giving the directory path to the proposal number (e.g.'/xtescratch/katja/cygex/P30157')
eband : energy band(s); in case you do not want to limit yourself to one eband once, you define in an array which ebands you want to sum up e.g. eband=[1,2,3] default: 1 (lowest energy band) NB: lowest eband has number 1, not 0! freqlimits : lower and upper frequency limits, the rms is to calculated for, e.g. for [0.1,1.,10.] the rms is calculated for three frequency bands default: min/max Fourier frequency n_pts : min. number of data points for the linear fit. When this number is smaller than n_pts, the program exits without result. default: 6 binnum : number of bins the flux range is divided into default: 20 minnum : min. number of data points in each time bin. When this number is smaller than minnum, the bin is left empty default: 4 fileoutput : controls output of result files, written to resultfile and plotfile default: no output to write result files, set fileoutput=1 chatty : controls screen output ; default: no output; to turn on screen output, set chatty=1 seglength : the length (in seconds) of a lightcurve segment default: 1 (s)
b : slope b of the linear fit dev_b : probable uncertainty sigma of b a : offset a of the linear fit dev_a : probable uncertainty sigma of a
the results of the linear fit are written to a file obspath+'/'+id+'/light/fourier/rmsflux/rmsfluxfit.txt' the linear fit plot is written to a file obspath+'/'+id+'/light/fourier/rmsflux/rmsfluxplot.ps'
xdrlc_r.pro fourierfreq.pro psd.pro dtcorr.pro rmsflux.pro rebinlc.pro
cygx1_rmsflux,'31.all.14off','/xtescratch/katja/cygex/P50110', $ fileoutput='1'
Version 1.0, 2002/02/22 TG (IAAT) Version 1.1, 2002/02/26 TG Use mpfitfun.pro to fit a linear function instead of linfit.pro (uses igamma.pro) as I often received the message "IGAMMA: failed to converge within given parameters" Version 1.2, 2002/03/12 JW optional keywords fn=fn,sn=sn,errsn=errsn added 2002/04/04 TG, JW fundamental change in the binning procedure: does not follow any more rebinlc.pro from the aitlib but uses now the vector notation 2002/04/23 TG now y=B*X+A AND y=k*(x-c) are fitted and saved 2003/03/07 TG, JW computes the uncertainties at the 90 % confidence level for the two interesting parameters k and C
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