FUNCTION BCS_DECOMP,inj,iwrap ;+ ; Program: BCS_DECOMP ; purpose: Decompression program for Solar_A BCS. ; Given a compressed value of counts in a bin, produce ; a true value of input counts. ; Uses a compression scheme of "constant error" designed by ; AF, produced by programm SCHEME_CONSTANT.PRO and ; programmed into EPROM on 5-Dec-1990 by Ian Belchamber. ; The maximum relative error (true-decompressed)/decompressed ; of this scheme is: ; 0 for decompressed values less or equal to 35. ; +- 0.0138 for decompressed values between 36.5 and 23724 ; (true input counts between 36 and 24051) ; +- 0.002 for decompressed values between 24100 and 65431 ; (true input counts between 24052 and 65535) ; The range of true values corresponding to the compressed ; value j is then (rounded to the nearest integer): ; from (1 - error)*value(j) to (1 + error)*value(j) ; where 'error' is one of the above values 0, 0.0138, 0.002 ; ; input: J = a scalar value or an array of integer compressed values ; A real number will be truncated to an integer. ; IWRAP: a scalar value, indicates whether normal ; decompression or wrapped around ; set iwrap to 24052 when wrapped around (to anything else ; when normal compression) ; output: VALUE = an array of decompressed counts. ; ; history: ; ; AF, MSSL 5-Dec-1990 written: ; RDB Feb 1991 made into a function ; RDB 18-Feb-91 renamed from DECOMPRESS to BCS_DECOMP ;- ; Convert to integer array, and allow for scalar value nj = N_elements(inj) if nj eq 1 then begin j = intarr(nj) j(0) = inj endif else j = fix(inj) ;; savej = j ;; j = intarr( N_elements(savej) ) ;; j(0) = savej ; silly cases can only be possible if input array is not a byte array ind = where(j lt 0) if ( ind(0) ge 0 ) then begin print,'$(a)',' **** Negative compressed value ***** ' stop endif ind = where(j ge 256) if ( ind(0) ge 0 ) then begin print,'$(a)', ' **** Compressed value has to be le 255 **** ' stop endif if n_params(0) eq 1 then iwrap=0 if (iwrap ne 24052 ) then begin ; normal decompression true = $ [ 0.0, 1.0, 2.0, 3.0, 4.0, 5.0, 6.0, 7.0,$ 8.0, 9.0, 10.0, 11.0, 12.0, 13.0, 14.0, 15.0,$ 16.0, 17.0, 18.0, 19.0, 20.0, 21.0, 22.0, 23.0,$ 24.0, 25.0, 26.0, 27.0, 28.0, 29.0, 30.0, 31.0,$ 32.0, 33.0, 34.0, 35.0, 36.5, 38.5, 40.5, 42.5,$ 44.5, 46.5, 48.5, 50.5, 52.5, 54.5, 56.5, 58.5,$ 60.5, 62.5, 64.5, 66.5, 68.5, 70.5, 73.0, 76.0,$ 79.0, 82.0, 85.0, 88.0, 91.0, 94.0, 97.0, 100.0,$ 103.0, 106.0, 109.5, 113.5, 117.5, 121.5, 125.5, 129.5,$ 133.5, 137.5, 141.5, 146.0, 151.0, 156.0, 161.0, 166.0,$ 171.0, 176.0, 181.5, 187.5, 193.5, 199.5, 205.5, 211.5] true = [true, $ 218.0, 225.0, 232.0, 239.0, 246.0, 253.0, 260.5, 268.5,$ 276.5, 284.5, 293.0, 302.0, 311.0, 320.0, 329.5, 339.5,$ 349.5, 359.5, 370.0, 381.0, 392.0, 403.5, 415.5, 427.5,$ 440.0, 453.0, 466.0, 479.5, 493.5, 508.0, 523.0, 538.0,$ 553.5, 569.5, 586.0, 603.0, 620.5, 638.5, 657.0, 676.0,$ 695.5, 715.5, 736.0, 757.0, 778.5, 801.0, 824.0, 847.5,$ 872.0, 897.0, 922.5, 949.0, 976.0, 1003.5, 1032.0, 1061.5,$ 1092.0, 1123.5, 1155.5, 1188.0, 1221.5, 1256.0, 1291.5, 1328.0,$ 1365.5, 1404.0, 1443.5, 1484.0, 1526.0, 1569.5, 1614.0, 1659.5,$ 1706.5, 1755.0, 1804.5, 1855.5, 1908.0, 1962.0, 2017.5, 2074.5] true = [true, $ 2133.0, 2193.0, 2255.0, 2319.0, 2384.5, 2451.5, 2520.5, 2591.5,$ 2664.5, 2739.5, 2816.5, 2895.5, 2977.0, 3061.0, 3147.0, 3235.5,$ 3326.5, 3420.0, 3516.5, 3615.5, 3717.0, 3821.5, 3929.0, 4039.5,$ 4153.0, 4269.5, 4389.5, 4513.0, 4640.0, 4770.5, 4904.5, 5042.5,$ 5184.5, 5330.5, 5480.5, 5634.5, 5792.5, 5955.0, 6122.0, 6293.5,$ 6470.0, 6651.5, 6838.0, 7030.0, 7227.5, 7430.5, 7639.0, 7853.0,$ 8073.0, 8299.5, 8532.5, 8772.0, 9018.0, 9270.5, 9530.5, 9798.0,$ 10073.0,10355.5,10645.5,10944.0,11251.0,11566.5,11891.0,12224.5,$ 12567.0,12919.0,13281.0,13653.0,14035.5,14429.0,14833.5,15249.0,$ 15676.0,16115.0,16566.5,17031.0,17508.5,17999.0,18503.0,19021.0,$ 19553.5,20101.0,20664.0,21243.0,21838.0,22449.5,23078.0,23724.0] endif else begin ; wrapped around ( input was ge 24052): true = $ [24100.0,24197.0,24294.5,24392.5,24490.5,24589.0,24688.0,24787.5,$ 24887.5,24987.5,25088.0,25189.0,25290.5,25392.5,25494.5,25597.0,$ 25700.0,25803.5,25907.5,26012.0,26117.0,26222.0,26327.5,26433.5,$ 26540.0,26647.0,26754.5,26862.5,26970.5,27079.0,27188.0,27297.5,$ 27407.5,27518.0,27629.0,27740.0,27851.5,27963.5,28076.0,28189.0,$ 28302.5,28416.5,28531.0,28646.0,28761.5,28877.5,28993.5,29110.0,$ 29227.0,29344.5,29462.5,29581.0,29700.0,29819.5,29939.5,30060.0,$ 30181.0,30302.5,30424.5,30547.0,30670.0,30793.5,30917.5,31042.0,$ 31167.0,31292.5,31418.5,31545.0,31672.0,31799.5,31927.5,32056.0,$ 32185.0,32314.5,32444.5,32575.0,32706.0,32837.5,32969.5,33102.0 ] true = [true, $ 33235.0,33368.5,33503.0,33638.0,33773.5,33909.5,34046.0,34183.0,$ 34320.5,34458.5,34597.0,34736.0,34875.5,35016.0,35157.0,35298.5,$ 35440.5,35583.0,35726.0,35869.5,36014.0,36159.0,36304.5,36450.5,$ 36597.0,36744.0,36891.5,37040.0,37189.0,37338.5,37488.5,37639.0,$ 37790.5,37942.5,38095.0,38248.0,38401.5,38556.0,38711.0,38866.5,$ 39023.0,39180.0,39337.5,39495.5,39654.0,39813.5,39973.5,40134.0,$ 40295.5,40457.5,40620.0,40783.5,40947.5,41112.0,41277.5,41443.5,$ 41610.0,41777.5,41945.5,42114.0,42283.5,42453.5,42624.0,42795.5,$ 42967.5,43140.0,43313.5,43487.5,43662.0,43837.5,44014.0,44191.0,$ 44368.5,44547.0,44726.0,44905.5,45086.0,45267.5,45449.5,45632.0 ] true = [true, $ 45815.5,46000.0,46185.0,46370.5,46557.0,46744.0,46931.5,47120.0,$ 47309.5,47500.0,47691.0,47882.5,48075.0,48268.5,48462.5,48657.0,$ 48852.5,49049.0,49246.0,49443.5,49642.0,49841.5,50042.0,50243.0,$ 50444.5,50647.0,50850.5,51055.0,51260.5,51466.5,51673.0,51880.5,$ 52089.0,52298.5,52509.0,52720.0,52931.5,53144.0,53357.5,53572.0,$ 53787.5,54004.0,54221.0,54438.5,54657.0,54876.5,55097.0,55318.5 ] true = [true, $ 55541.0,55764.5,55988.5,56213.0,56438.5,56665.0,56892.5,57121.0,$ 57350.5,57581.0,57812.5,58045.0,58278.5,58513.0,58748.0,58983.5,$ 59220.0,59457.5,59696.0,59935.5,60176.0,60417.5,60660.0,60903.5,$ 61148.0,61393.5,61640.0,61887.5,62136.0,62385.5,62636.0,62887.5,$ 63140.0,63393.5,63648.0,63903.5,64160.0,64417.5,64676.0,64935.5,$ 65196.0,65431.0 ] nt = N_elements(true) if ( max(j) ge nt ) then begin print,'$(a,i3)', ' ** WRAP AROUND - compressed value has to be le ',nt-1 stop endif endelse value = true(j) return,value end