function cbar_zenith, dummy $ , bw=bw_, D0=D0, black_bkg=black_bkg, notable=notable $ , gray=gray, wrap=wrap, invert=invert_, min=min_, max=max_ ;+ ; ; function: cbar_zenith ; ; purpose: Return tvasp zenith color bar image. ; ; author: paul@ncar, 4/96 ; ;============================================================================== ; ; Check number of parameters. ; if n_params() ne 0 then begin print print, "usage: azbar = cbar_zenith()" print print, " Return tvasp zenith color bar image." print print, "keywords:" print, " bw - set to get black & white lithograph." print, " min - min keyword for tvasp.pro (def: 0 )" print, " max - max keyword for tvasp.pro (def: 180 )" print, " invert - invert keyword for tvasp.pro (def: bw )" print, " wrap - wrap keyword for tvasp.pro (def: unset)" print, " gray - gray keyword for tvasp.pro (def: unset)" print, " D0 - y dimension of returned image" print, " x dimension is half this size." print, " (def: 100)." print print, " notable - set to prevent tvasp from loading" print, " color table (def: load color table)." print print, " black_bkg - set to make background black" print, " (def: make background white)." print print, "ex:" print, " ; Display zenith color bar at 0,0 in window." print, " tv, cbar_zenith(), 0,0" print print, " ; Compute 100x200 zenith color bar image." print, " cbar_image = cbar_zenith(D0=200)" print print, " ; Compute 100x200 zenith color bar image," print, " ; use black background and prevent loading" print, " ; tvasp color table." print, " cbar_image = cbar_zenith(D0=200,/black,/notable)" return, 0 endif ;- ;Set black & white lithograph. bw = keyword_set(bw_) ;Set wrap or default. if n_elements(invert_) eq 0 then invert=bw else invert=invert_ ;Set min max or default. if n_elements(min_) eq 0 then min=0 else min=min_ if n_elements(max_) eq 0 then max=180 else max=max_ ;Set image dimensions. if n_elements(D0) ne 0 then ydim=round(D0) else ydim=100L xdim = ydim/2 ;Rasters arrays of x & y. tmp = lindgen(xdim,ydim) yrast = tmp/xdim xrast = tmp-yrast*xdim ;Where colors are in the image. radius = xdim-1. whr = where( xrast^2+(yrast-radius)^2 le radius^2 ) ;Array with zenuth angle values. tmp = replicate(1000.,xdim,ydim) tmp(whr) = atan( xrast(whr), yrast(whr)-radius )*(180./!pi) ;Background where array. if keyword_set( black_bkg ) $ then bbkg = where( tmp eq 1000. ) $ else wbkg = where( tmp eq 1000. ) ;Compute byte image. tvasp, tmp, bi=bi, min=min, max=max $ , bw=bw, white=wbkg, black=bbkg, /notv, notable=notable $ , gray=gray, wrap=wrap, invert=invert ;Return byte image. return, bi end