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MaplePrimes Posts are for sharing your experiences, techniques and opinions about Maple, MapleSim and related products, as well as general interests in math and computing.

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  • I would like to pay attention to a series of applications by Samir Khan
    http://www.maplesoft.com/applications/view.aspx?SID=153600
    http://www.maplesoft.com/applications/view.aspx?SID=153599
    http://www.maplesoft.com/applications/view.aspx?SID=153596
    http://www.maplesoft.com/applications/view.aspx?SID=153598
    My congratulations to the author on his work well done. New capacities of Global Optimization Toolbox are spectacular. For example, in the first application  an optimization
    problem in 101 variables under 5050 nonlinear  constraints
    (other than 202 bounds) is solved.
    I think it requires a very powerful comp and much time.
    I tried that  problem for n=20 with the good old DirectSearch
    on my comp (4 GB RAM, Pentium Dual-Core CPU E5700@3GHz) by

    soln2 := DirectSearch:-GlobalSearch(rc, {cons1, cons2, rc >= 0,
    seq(`and`(vars[i] >= -70, vars[i] <= 70), i = 1 .. 2*n), rc <= 70},
    variables = vars, method = quadratic, number = 140, solutions = 1,
    evaluationlimit = 20000)

    and obtained not so bad rc=69.9609360106765 (whereas www.packomania.com gives rc=58.4005674790451137175957) in about one hour.

    Packing_by_DS.mw
    For n=50 the memory of my comp cannot allocate calculations or the obtained result by the Search command is far away from the one in packomania.

     

    You guys might find this article interesting.

    It presents a linear algebra problem, then writes a program to solve it in Maple, Mathematica, and Maxima to see which one is better. What do you think?

    Maplesoft regularly hosts live webinars on a variety of topics. Below you will find details on an upcoming webinar we think may be of interest to the MaplePrimes community.  For the complete list of upcoming webinars, visit our website.

    Hollywood Math 2

    In this second installment of the Hollywood Math webinar series, we will present some more examples of mathematics being used in Hollywood films and popular hit TV series. For instance, have you wondered how Ben Campbell solved his professor’s challenge so easily in the movie “21”? Or about the details of the Nash equilibrium that John Nash first developed in a “A Beautiful Mind”? We’ve got the answers! These relevant, and exciting examples can be used as material to engage your students with examples familiar to them, or you can just attend the webinar for its entertainment value.

    Anyone with an interest in mathematics, especially high school and early college math educators, will be both entertained and informed by attending this webinar. At the end of the webinar you’ll be given an opportunity to download an application containing all of the examples that we demonstrate.

    To join us for the live presentation, please click here to register.

    If you missed the first webinar in this two part series, you can view the 'Hollywood Math' recording on our website.

    Here is an example of manipulating an Array of pixels. I chose the x-rite ColorChecker as a model so there would be published results to check my work. A number of details about color spaces have become clear through this exercise. The color adaptation process was modeled by converting betweenXYZ and LMS. Different black points may be selected depending on how close to zero illuminance one would accept as a good model. 

    I look forward to extending this work to verify and improve the color calibration of my photography. Also some experimentation with demosaicing should be possible.

    Initialization

     

    restart

    with(LinearAlgebra):

    unprotect(gamma):``

    NULL

    x-rite Colorchecker xyY Matrix

      CCxyY_D50 := Matrix(4, 6, {(1, 1) = Vector(3, {(1) = .4316, (2) = .3777, (3) = .1008}), (1, 2) = Vector(3, {(1) = .4197, (2) = .3744, (3) = .3495}), (1, 3) = Vector(3, {(1) = .2760, (2) = .3016, (3) = .1836}), (1, 4) = Vector(3, {(1) = .3703, (2) = .4499, (3) = .1325}), (1, 5) = Vector(3, {(1) = .2999, (2) = .2856, (3) = .2304}), (1, 6) = Vector(3, {(1) = .2848, (2) = .3911, (3) = .4178}), (2, 1) = Vector(3, {(1) = .5295, (2) = .4055, (3) = .3118}), (2, 2) = Vector(3, {(1) = .2305, (2) = .2106, (3) = .1126}), (2, 3) = Vector(3, {(1) = .5012, (2) = .3273, (3) = .1938}), (2, 4) = Vector(3, {(1) = .3319, (2) = .2482, (3) = 0.637e-1}), (2, 5) = Vector(3, {(1) = .3984, (2) = .5008, (3) = .4446}), (2, 6) = Vector(3, {(1) = .4957, (2) = .4427, (3) = .4357}), (3, 1) = Vector(3, {(1) = .2018, (2) = .1692, (3) = 0.575e-1}), (3, 2) = Vector(3, {(1) = .3253, (2) = .5032, (3) = .2318}), (3, 3) = Vector(3, {(1) = .5686, (2) = .3303, (3) = .1257}), (3, 4) = Vector(3, {(1) = .4697, (2) = .4734, (3) = .5981}), (3, 5) = Vector(3, {(1) = .4159, (2) = .2688, (3) = .2009}), (3, 6) = Vector(3, {(1) = .2131, (2) = .3023, (3) = .1930}), (4, 1) = Vector(3, {(1) = .3469, (2) = .3608, (3) = .9131}), (4, 2) = Vector(3, {(1) = .3440, (2) = .3584, (3) = .5894}), (4, 3) = Vector(3, {(1) = .3432, (2) = .3581, (3) = .3632}), (4, 4) = Vector(3, {(1) = .3446, (2) = .3579, (3) = .1915}), (4, 5) = Vector(3, {(1) = .3401, (2) = .3548, (3) = 0.883e-1}), (4, 6) = Vector(3, {(1) = .3406, (2) = .3537, (3) = 0.311e-1})})

    NULL

    NULL

    M := RowDimension(CCxyY_D50) = 4NULL

    N := ColumnDimension(CCxyY_D50) = 6

    NULL

    Convert xyY to XYZ

       

    NULL

    CCXYZ_D50 := C_xyY_to_XYZ(CCxyY_D50):

    CCXYZ_D50 = Matrix(4, 6, {(1, 1) = Vector(3, {(1) = .1152, (2) = .1008, (3) = 0.509e-1}), (1, 2) = Vector(3, {(1) = .3918, (2) = .3495, (3) = .1922}), (1, 3) = Vector(3, {(1) = .1680, (2) = .1836, (3) = .2571}), (1, 4) = Vector(3, {(1) = .1091, (2) = .1325, (3) = 0.529e-1}), (1, 5) = Vector(3, {(1) = .2419, (2) = .2304, (3) = .3344}), (1, 6) = Vector(3, {(1) = .3042, (2) = .4178, (3) = .3462}), (2, 1) = Vector(3, {(1) = .4071, (2) = .3118, (3) = 0.500e-1}), (2, 2) = Vector(3, {(1) = .1232, (2) = .1126, (3) = .2988}), (2, 3) = Vector(3, {(1) = .2968, (2) = .1938, (3) = .1015}), (2, 4) = Vector(3, {(1) = 0.852e-1, (2) = 0.637e-1, (3) = .1078}), (2, 5) = Vector(3, {(1) = .3537, (2) = .4446, (3) = 0.895e-1}), (2, 6) = Vector(3, {(1) = .4879, (2) = .4357, (3) = 0.606e-1}), (3, 1) = Vector(3, {(1) = 0.686e-1, (2) = 0.575e-1, (3) = .2138}), (3, 2) = Vector(3, {(1) = .1498, (2) = .2318, (3) = 0.790e-1}), (3, 3) = Vector(3, {(1) = .2164, (2) = .1257, (3) = 0.385e-1}), (3, 4) = Vector(3, {(1) = .5934, (2) = .5981, (3) = 0.719e-1}), (3, 5) = Vector(3, {(1) = .3108, (2) = .2009, (3) = .2356}), (3, 6) = Vector(3, {(1) = .1360, (2) = .1930, (3) = .3094}), (4, 1) = Vector(3, {(1) = .8779, (2) = .9131, (3) = .7397}), (4, 2) = Vector(3, {(1) = .5657, (2) = .5894, (3) = .4894}), (4, 3) = Vector(3, {(1) = .3481, (2) = .3632, (3) = .3029}), (4, 4) = Vector(3, {(1) = .1844, (2) = .1915, (3) = .1592}), (4, 5) = Vector(3, {(1) = 0.846e-1, (2) = 0.883e-1, (3) = 0.759e-1}), (4, 6) = Vector(3, {(1) = 0.299e-1, (2) = 0.311e-1, (3) = 0.269e-1})})NULL

    XYZ D50 to XYZ D65

       

    NULL

    CCXYZ_D65 := XYZ_D50_to_D65(CCXYZ_D50):

    CCXYZ_D65 = Matrix(4, 6, {(1, 1) = Vector(3, {(1) = .1110, (2) = 0.996e-1, (3) = 0.670e-1}), (1, 2) = Vector(3, {(1) = .3785, (2) = .3459, (3) = .2533}), (1, 3) = Vector(3, {(1) = .1726, (2) = .1861, (3) = .3403}), (1, 4) = Vector(3, {(1) = .1045, (2) = .1318, (3) = 0.690e-1}), (1, 5) = Vector(3, {(1) = .2470, (2) = .2329, (3) = .4430}), (1, 6) = Vector(3, {(1) = .3030, (2) = .4206, (3) = .4556}), (2, 1) = Vector(3, {(1) = .3850, (2) = .3044, (3) = 0.651e-1}), (2, 2) = Vector(3, {(1) = .1340, (2) = .1165, (3) = .3966}), (2, 3) = Vector(3, {(1) = .2855, (2) = .1895, (3) = .1347}), (2, 4) = Vector(3, {(1) = 0.867e-1, (2) = 0.642e-1, (3) = .1431}), (2, 5) = Vector(3, {(1) = .3334, (2) = .4409, (3) = .1142}), (2, 6) = Vector(3, {(1) = .4600, (2) = .4275, (3) = 0.777e-1}), (3, 1) = Vector(3, {(1) = 0.777e-1, (2) = 0.606e-1, (3) = .2839}), (3, 2) = Vector(3, {(1) = .1428, (2) = .2315, (3) = .1022}), (3, 3) = Vector(3, {(1) = .2063, (2) = .1216, (3) = 0.512e-1}), (3, 4) = Vector(3, {(1) = .5578, (2) = .5888, (3) = 0.906e-1}), (3, 5) = Vector(3, {(1) = .3073, (2) = .1990, (3) = .3131}), (3, 6) = Vector(3, {(1) = .1451, (2) = .1976, (3) = .4092}), (4, 1) = Vector(3, {(1) = .8646, (2) = .9129, (3) = .9759}), (4, 2) = Vector(3, {(1) = .5579, (2) = .5895, (3) = .6458}), (4, 3) = Vector(3, {(1) = .3434, (2) = .3633, (3) = .3997}), (4, 4) = Vector(3, {(1) = .1818, (2) = .1915, (3) = .2100}), (4, 5) = Vector(3, {(1) = 0.836e-1, (2) = 0.884e-1, (3) = .1002}), (4, 6) = Vector(3, {(1) = 0.296e-1, (2) = 0.311e-1, (3) = 0.355e-1})})

    NULL

    NULLConvert XYZ to Lab (D50 or D65 White Point)

     

    NULLNULL

    Reference White Point for D50

    NULL

    X_D50wht := XYZ_D50wht[1] = .96422NULL

    Y_D50wht := XYZ_D50wht[2] = 1NULL

    Z_D50wht := XYZ_D50wht[3] = .82521

    NULL

    Lab Conversion Constants;

    `&epsilon;` := 216/24389:

    kappa := 24389/27:

    NULL

    fx_D50 := proc (XYZ) options operator, arrow; piecewise(`&epsilon;` < XYZ[1]/X_D50wht, (XYZ[1]/X_D50wht)^(1/3), XYZ[1]/X_D50wht <= `&epsilon;`, (1/116)*kappa*XYZ[1]/X_D50wht+4/29) end proc
                    

    NULLNULL

    NULL

     
    fy_D50 := proc (XYZ) options operator, arrow; piecewise(`&epsilon;` < XYZ[2]/Y_D50wht, (XYZ[2]/Y_D50wht)^(1/3), XYZ[2]/Y_D50wht <= `&epsilon;`, (1/116)*kappa*XYZ[2]/Y_D50wht+4/29) end proc
    NULLNULL

    NULLNULL

    fz_D50 := proc (XYZ) options operator, arrow; piecewise(`&epsilon;` < XYZ[3]/Z_D50wht, (XYZ[3]/Z_D50wht)^(1/3), XYZ[3]/Z_D50wht <= `&epsilon;`, (1/116)*kappa*XYZ[3]/Z_D50wht+4/29) end proc
    NULL

    XYZ_to_Lab_D50 := proc (XYZ) options operator, arrow; `<,>`(116*fy_D50(XYZ)-16, 500*fx_D50(XYZ)-500*fy_D50(XYZ), 200*fy_D50(XYZ)-200*fz_D50(XYZ)) end proc:

    NULL

    Reference White Point for D65

    NULL

    X_D65wht := XYZ_D65wht[1] = .95047NULL

    Y_D65wht := XYZ_D65wht[2] = 1NULL

    Z_D65wht := XYZ_D65wht[3] = 1.08883 

    NULL

    NULL

    NULL

    NULL

    NULL

    NULL

    NULL

    fx_D65 := proc (XYZ) options operator, arrow; piecewise(`&epsilon;` < XYZ[1]/X_D65wht, (XYZ[1]/X_D65wht)^(1/3), XYZ[1]/X_D65wht <= `&epsilon;`, (1/116)*kappa*XYZ[1]/X_D65wht+4/29) end proc
                    

    NULLNULL

    NULL

     
    fy_D65 := proc (XYZ) options operator, arrow; piecewise(`&epsilon;` < XYZ[2]/Y_D65wht, (XYZ[2]/Y_D65wht)^(1/3), XYZ[2]/Y_D65wht <= `&epsilon;`, (1/116)*kappa*XYZ[2]/Y_D65wht+4/29) end proc
    NULLNULL

    NULLNULL

    fz_D65 := proc (XYZ) options operator, arrow; piecewise(`&epsilon;` < XYZ[3]/Z_D65wht, (XYZ[3]/Z_D65wht)^(1/3), XYZ[3]/Z_D65wht <= `&epsilon;`, (1/116)*kappa*XYZ[3]/Z_D65wht+4/29) end proc
    NULL

    XYZ_to_Lab_D65 := proc (XYZ) options operator, arrow; `<,>`(116*fy_D65(XYZ)-16, 500*fx_D65(XYZ)-500*fy_D65(XYZ), 200*fy_D65(XYZ)-200*fz_D65(XYZ)) end proc:

    NULL

    NULL

     

    NULL

    C_XYZ_to_Lab := proc (XYZ, L) options operator, arrow; piecewise(evalb(L = D50), Array([`$`('[`$`('XYZ_to_Lab_D50(XYZ[m, n])', n = 1 .. N)]', m = 1 .. M)]), evalb(L = D65), Array([`$`('[`$`('XYZ_to_Lab_D65(XYZ[m, n])', n = 1 .. N)]', m = 1 .. M)])) end proc
     NULL

    NULL

    NULLNULL

    NULL

    CCLab_D50 := C_XYZ_to_Lab(CCXYZ_D50, D50): NULL

    CCLab_D50 = Matrix(4, 6, {(1, 1) = Vector(3, {(1) = 37.99, (2) = 13.55, (3) = 14.06}), (1, 2) = Vector(3, {(1) = 65.71, (2) = 18.14, (3) = 17.82}), (1, 3) = Vector(3, {(1) = 49.93, (2) = -4.91, (3) = -21.92}), (1, 4) = Vector(3, {(1) = 43.14, (2) = -13.10, (3) = 21.89}), (1, 5) = Vector(3, {(1) = 55.11, (2) = 8.84, (3) = -25.39}), (1, 6) = Vector(3, {(1) = 70.72, (2) = -33.39, (3) = -.21}), (2, 1) = Vector(3, {(1) = 62.66, (2) = 36.06, (3) = 57.08}), (2, 2) = Vector(3, {(1) = 40.01, (2) = 10.42, (3) = -45.98}), (2, 3) = Vector(3, {(1) = 51.13, (2) = 48.24, (3) = 16.26}), (2, 4) = Vector(3, {(1) = 30.33, (2) = 23.00, (3) = -21.59}), (2, 5) = Vector(3, {(1) = 72.53, (2) = -23.70, (3) = 57.27}), (2, 6) = Vector(3, {(1) = 71.94, (2) = 19.37, (3) = 67.86}), (3, 1) = Vector(3, {(1) = 28.77, (2) = 14.17, (3) = -50.30}), (3, 2) = Vector(3, {(1) = 55.26, (2) = -38.32, (3) = 31.36}), (3, 3) = Vector(3, {(1) = 42.11, (2) = 53.38, (3) = 28.20}), (3, 4) = Vector(3, {(1) = 81.73, (2) = 4.03, (3) = 79.85}), (3, 5) = Vector(3, {(1) = 51.94, (2) = 50.00, (3) = -14.57}), (3, 6) = Vector(3, {(1) = 51.04, (2) = -28.65, (3) = -28.63}), (4, 1) = Vector(3, {(1) = 96.54, (2) = -.46, (3) = 1.19}), (4, 2) = Vector(3, {(1) = 81.26, (2) = -.64, (3) = -.35}), (4, 3) = Vector(3, {(1) = 66.76, (2) = -.72, (3) = -.51}), (4, 4) = Vector(3, {(1) = 50.86, (2) = -.14, (3) = -.28}), (4, 5) = Vector(3, {(1) = 35.65, (2) = -.44, (3) = -1.23}), (4, 6) = Vector(3, {(1) = 20.48, (2) = -0.7e-1, (3) = -.98})})NULL

    NULL

    Convert XYZ to aRGB (XYZ D50 or D65 to aRGB D65)

     

    XYZ Scaling for aRGB Ymax,Ymin (Ref. Adobe RGB (1998) Color Image Encoding Section 4.3.2.2 and 4.3.8)

    NULL

    White Point (Luminance=160Cd/m^2) D65

    Black Point (Luminance=0.5557Cd/m^2) D65

    White Point (Luminance=160Cd/m^2) D50

    Black Point (Luminance=0.5557Cd/m^2) D50

    XW_D65 := 152.07*(1/160) = .9504375000NULL

    YW_D65 := 160*(1/160) = 1``

    ZW_D65 := 174.25*(1/160) = 1.089062500``

    NULL

    xXK_D65 := .5282*(1/160) = 0.3301250000e-2``

    xYK_D65 := .5557*(1/160) = 0.3473125000e-2``

    xZK_D65 := .6025*(1/160) = 0.3765625000e-2``

    XK_D65 := 0:

    YK_D65 := 0:

    ZK_D65 := 0:

    ``

    ``

    XW_D50 := .9462:NULL

    YW_D50 := 1.0000:

    ZW_D50 := .8249:

    ``

    NULL

    xXK_D50 := 0.33488e-2:

    xYK_D50 := 0.34751e-2:

    xZK_D50 := 0.28650e-2:

    ``

    XK_D50 := 0:

    YK_D50 := 0:

    ZK_D50 := 0:

    NULL

     

    NULL

    XYZD65_to_aXYZ := proc (XYZ) options operator, arrow; `<,>`((XYZ[1]-XK_D65)*XW_D65/((XW_D65-XK_D65)*YW_D65), (XYZ[2]-YK_D65)/(YW_D65-YK_D65), (XYZ[3]-ZK_D65)*ZW_D65/((ZW_D65-ZK_D65)*YW_D65)) end proc:

    XYZD50_to_aXYZ := proc (XYZ) options operator, arrow; `<,>`((XYZ[1]-XK_D50)*XW_D50/((XW_D50-XK_D50)*YW_D50), (XYZ[2]-YK_D50)/(YW_D50-YK_D50), (XYZ[3]-ZK_D50)*ZW_D50/((ZW_D50-ZK_D50)*YW_D50)) end proc:

     

    NULL

    (ref. Adobe RGB(1998) section 4.3.6.1, Bradford Matrix includes D50 to D65 adaptation)

    M_XYZtoaRGB_D50 := Matrix(3, 3, {(1, 1) = 1.96253, (1, 2) = -.61068, (1, 3) = -.34137, (2, 1) = -.97876, (2, 2) = 1.91615, (2, 3) = 0.3342e-1, (3, 1) = 0.2869e-1, (3, 2) = -.14067, (3, 3) = 1.34926})

      aXYZ_to_RGB_D50 := proc (aXYZ) options operator, arrow; `<,>`(Typesetting:-delayDotProduct(M_XYZtoaRGB_D50, aXYZ)) end proc: NULL

     

    (ref. Adobe RBG(1998) section 4.3.4.1, Bradford Matrix assumes XYZ is D65)

    M_XYZtoaRGB_D65 := Matrix(3, 3, {(1, 1) = 2.04159, (1, 2) = -.56501, (1, 3) = -.34473, (2, 1) = -.96924, (2, 2) = 1.87597, (2, 3) = 0.4156e-1, (3, 1) = 0.1344e-1, (3, 2) = -.11836, (3, 3) = 1.01517})

      NULL

    aXYZ_to_RGB_D65 := proc (aXYZ) options operator, arrow; `<,>`(Typesetting:-delayDotProduct(M_XYZtoaRGB_D65, aXYZ)) end proc:

    NULL

      aRGB Expansion for 8bits

     

    `&gamma;a` := 2.19921875:

    RGB_to_aRGB := proc (RGB) options operator, arrow; `<,>`(round(255*Norm(RGB[1])^(1/`&gamma;a`)), round(255*Norm(RGB[2])^(1/`&gamma;a`)), round(255*Norm(RGB[3])^(1/`&gamma;a`))) end proc:
    NULL

     

    Combine Steps

    NULL

    XYZ_to_aRGB := proc (XYZ, L) options operator, arrow; piecewise(evalb(L = D50), Array([`$`('[`$`('RGB_to_aRGB(aXYZ_to_RGB_D50(XYZD50_to_aXYZ(XYZ[m, n])))', n = 1 .. N)]', m = 1 .. M)]), evalb(L = D65), Array([`$`('[`$`('RGB_to_aRGB(aXYZ_to_RGB_D65(XYZD65_to_aXYZ(XYZ[m, n])))', n = 1 .. N)]', m = 1 .. M)])) end proc

    NULLNULL

    NULLNULL

    Note: The aRGB values published for ColorChecker assume a black point of 0cd/m^2.

    ````

    aRGB_D50in := XYZ_to_aRGB(CCXYZ_D50, D50):

    aRGB_D50in = Matrix(4, 6, {(1, 1) = Vector(3, {(1) = 107, (2) = 82, (3) = 70}), (1, 2) = Vector(3, {(1) = 184, (2) = 146, (3) = 128}), (1, 3) = Vector(3, {(1) = 101, (2) = 122, (3) = 153}), (1, 4) = Vector(3, {(1) = 95, (2) = 107, (3) = 69}), (1, 5) = Vector(3, {(1) = 128, (2) = 127, (3) = 173}), (1, 6) = Vector(3, {(1) = 129, (2) = 188, (3) = 171}), (2, 1) = Vector(3, {(1) = 201, (2) = 123, (3) = 56}), (2, 2) = Vector(3, {(1) = 77, (2) = 92, (3) = 166}), (2, 3) = Vector(3, {(1) = 174, (2) = 83, (3) = 97}), (2, 4) = Vector(3, {(1) = 86, (2) = 61, (3) = 104}), (2, 5) = Vector(3, {(1) = 167, (2) = 188, (3) = 75}), (2, 6) = Vector(3, {(1) = 213, (2) = 160, (3) = 55}), (3, 1) = Vector(3, {(1) = 49, (2) = 65, (3) = 143}), (3, 2) = Vector(3, {(1) = 99, (2) = 148, (3) = 80}), (3, 3) = Vector(3, {(1) = 155, (2) = 52, (3) = 59}), (3, 4) = Vector(3, {(1) = 227, (2) = 197, (3) = 52}), (3, 5) = Vector(3, {(1) = 169, (2) = 85, (3) = 147}), (3, 6) = Vector(3, {(1) = 61, (2) = 135, (3) = 167}), (4, 1) = Vector(3, {(1) = 245, (2) = 245, (3) = 242}), (4, 2) = Vector(3, {(1) = 200, (2) = 201, (3) = 201}), (4, 3) = Vector(3, {(1) = 160, (2) = 161, (3) = 162}), (4, 4) = Vector(3, {(1) = 120, (2) = 120, (3) = 121}), (4, 5) = Vector(3, {(1) = 84, (2) = 85, (3) = 86}), (4, 6) = Vector(3, {(1) = 52, (2) = 53, (3) = 54})})NULL

      

    NULL

    aRGB_D65in := XYZ_to_aRGB(CCXYZ_D65, D65):

    aRGB_D65in = Matrix(4, 6, {(1, 1) = Vector(3, {(1) = 107, (2) = 82, (3) = 70}), (1, 2) = Vector(3, {(1) = 184, (2) = 146, (3) = 128}), (1, 3) = Vector(3, {(1) = 101, (2) = 122, (3) = 153}), (1, 4) = Vector(3, {(1) = 95, (2) = 107, (3) = 69}), (1, 5) = Vector(3, {(1) = 128, (2) = 127, (3) = 173}), (1, 6) = Vector(3, {(1) = 129, (2) = 188, (3) = 171}), (2, 1) = Vector(3, {(1) = 201, (2) = 123, (3) = 56}), (2, 2) = Vector(3, {(1) = 77, (2) = 92, (3) = 166}), (2, 3) = Vector(3, {(1) = 174, (2) = 83, (3) = 97}), (2, 4) = Vector(3, {(1) = 86, (2) = 61, (3) = 104}), (2, 5) = Vector(3, {(1) = 167, (2) = 188, (3) = 75}), (2, 6) = Vector(3, {(1) = 213, (2) = 160, (3) = 55}), (3, 1) = Vector(3, {(1) = 49, (2) = 65, (3) = 143}), (3, 2) = Vector(3, {(1) = 99, (2) = 148, (3) = 80}), (3, 3) = Vector(3, {(1) = 155, (2) = 52, (3) = 59}), (3, 4) = Vector(3, {(1) = 227, (2) = 197, (3) = 52}), (3, 5) = Vector(3, {(1) = 169, (2) = 85, (3) = 147}), (3, 6) = Vector(3, {(1) = 61, (2) = 135, (3) = 167}), (4, 1) = Vector(3, {(1) = 245, (2) = 245, (3) = 242}), (4, 2) = Vector(3, {(1) = 200, (2) = 201, (3) = 201}), (4, 3) = Vector(3, {(1) = 160, (2) = 161, (3) = 162}), (4, 4) = Vector(3, {(1) = 120, (2) = 120, (3) = 121}), (4, 5) = Vector(3, {(1) = 84, (2) = 85, (3) = 86}), (4, 6) = Vector(3, {(1) = 52, (2) = 53, (3) = 54})})

    Convert XYZ to ProPhoto RGB (D50)

       

    NULL

    CC_PPhoto := XYZ_to_PPhoto(CCXYZ_D50):

    NULL

    CC_PPhoto = Matrix(4, 6, {(1, 1) = Vector(3, {(1) = 81, (2) = 67, (3) = 54}), (1, 2) = Vector(3, {(1) = 159, (2) = 135, (3) = 113}), (1, 3) = Vector(3, {(1) = 94, (2) = 102, (3) = 133}), (1, 4) = Vector(3, {(1) = 75, (2) = 86, (3) = 55}), (1, 5) = Vector(3, {(1) = 118, (2) = 111, (3) = 154}), (1, 6) = Vector(3, {(1) = 127, (2) = 168, (3) = 157}), (2, 1) = Vector(3, {(1) = 167, (2) = 118, (3) = 54}), (2, 2) = Vector(3, {(1) = 79, (2) = 74, (3) = 145}), (2, 3) = Vector(3, {(1) = 141, (2) = 83, (3) = 80}), (2, 4) = Vector(3, {(1) = 68, (2) = 49, (3) = 82}), (2, 5) = Vector(3, {(1) = 144, (2) = 170, (3) = 74}), (2, 6) = Vector(3, {(1) = 181, (2) = 152, (3) = 60}), (3, 1) = Vector(3, {(1) = 57, (2) = 50, (3) = 120}), (3, 2) = Vector(3, {(1) = 85, (2) = 123, (3) = 69}), (3, 3) = Vector(3, {(1) = 120, (2) = 59, (3) = 46}), (3, 4) = Vector(3, {(1) = 199, (2) = 188, (3) = 66}), (3, 5) = Vector(3, {(1) = 143, (2) = 85, (3) = 127}), (3, 6) = Vector(3, {(1) = 78, (2) = 111, (3) = 148}), (4, 1) = Vector(3, {(1) = 242, (2) = 243, (3) = 240}), (4, 2) = Vector(3, {(1) = 189, (2) = 190, (3) = 191}), (4, 3) = Vector(3, {(1) = 145, (2) = 146, (3) = 146}), (4, 4) = Vector(3, {(1) = 102, (2) = 102, (3) = 102}), (4, 5) = Vector(3, {(1) = 66, (2) = 66, (3) = 68}), (4, 6) = Vector(3, {(1) = 37, (2) = 37, (3) = 38})})NULL

    Convert XYZ to sRGB (XYZ D50 or D65 to sRGB D65)

       

    NULL

    Note: The sRGB values published for ColorChecker assume a black point of 0cd/m^2.

    ``

    CCsRGB_D65in := XYZ_to_sRGB(CCXYZ_D65, D65):

    NULL

    CCsRGB_D65in = Matrix(4, 6, {(1, 1) = Vector(3, {(1) = 115, (2) = 81, (3) = 67}), (1, 2) = Vector(3, {(1) = 199, (2) = 147, (3) = 129}), (1, 3) = Vector(3, {(1) = 91, (2) = 122, (3) = 156}), (1, 4) = Vector(3, {(1) = 90, (2) = 108, (3) = 64}), (1, 5) = Vector(3, {(1) = 130, (2) = 128, (3) = 176}), (1, 6) = Vector(3, {(1) = 92, (2) = 190, (3) = 172}), (2, 1) = Vector(3, {(1) = 224, (2) = 124, (3) = 47}), (2, 2) = Vector(3, {(1) = 68, (2) = 91, (3) = 170}), (2, 3) = Vector(3, {(1) = 198, (2) = 82, (3) = 97}), (2, 4) = Vector(3, {(1) = 94, (2) = 58, (3) = 106}), (2, 5) = Vector(3, {(1) = 159, (2) = 189, (3) = 63}), (2, 6) = Vector(3, {(1) = 230, (2) = 162, (3) = 39}), (3, 1) = Vector(3, {(1) = 35, (2) = 63, (3) = 147}), (3, 2) = Vector(3, {(1) = 67, (2) = 149, (3) = 74}), (3, 3) = Vector(3, {(1) = 180, (2) = 49, (3) = 57}), (3, 4) = Vector(3, {(1) = 238, (2) = 198, (3) = 20}), (3, 5) = Vector(3, {(1) = 193, (2) = 84, (3) = 151}), (3, 6) = Vector(3, {(1) = 54, (2) = 136, (3) = 170}), (4, 1) = Vector(3, {(1) = 245, (2) = 245, (3) = 243}), (4, 2) = Vector(3, {(1) = 200, (2) = 202, (3) = 202}), (4, 3) = Vector(3, {(1) = 161, (2) = 163, (3) = 163}), (4, 4) = Vector(3, {(1) = 121, (2) = 121, (3) = 122}), (4, 5) = Vector(3, {(1) = 82, (2) = 84, (3) = 86}), (4, 6) = Vector(3, {(1) = 49, (2) = 49, (3) = 51})})NULL

    ``

    CCsRGB_D50in := XYZ_to_sRGB(CCXYZ_D50, D50):

    ``

    CCsRGB_D50in = Matrix(4, 6, {(1, 1) = Vector(3, {(1) = 115, (2) = 81, (3) = 67}), (1, 2) = Vector(3, {(1) = 199, (2) = 148, (3) = 129}), (1, 3) = Vector(3, {(1) = 91, (2) = 123, (3) = 156}), (1, 4) = Vector(3, {(1) = 90, (2) = 108, (3) = 64}), (1, 5) = Vector(3, {(1) = 130, (2) = 129, (3) = 176}), (1, 6) = Vector(3, {(1) = 92, (2) = 190, (3) = 172}), (2, 1) = Vector(3, {(1) = 224, (2) = 125, (3) = 47}), (2, 2) = Vector(3, {(1) = 68, (2) = 92, (3) = 170}), (2, 3) = Vector(3, {(1) = 198, (2) = 83, (3) = 97}), (2, 4) = Vector(3, {(1) = 94, (2) = 59, (3) = 106}), (2, 5) = Vector(3, {(1) = 159, (2) = 190, (3) = 63}), (2, 6) = Vector(3, {(1) = 230, (2) = 163, (3) = 39}), (3, 1) = Vector(3, {(1) = 35, (2) = 64, (3) = 147}), (3, 2) = Vector(3, {(1) = 67, (2) = 149, (3) = 74}), (3, 3) = Vector(3, {(1) = 180, (2) = 51, (3) = 57}), (3, 4) = Vector(3, {(1) = 238, (2) = 199, (3) = 20}), (3, 5) = Vector(3, {(1) = 193, (2) = 85, (3) = 151}), (3, 6) = Vector(3, {(1) = 54, (2) = 137, (3) = 170}), (4, 1) = Vector(3, {(1) = 245, (2) = 246, (3) = 243}), (4, 2) = Vector(3, {(1) = 200, (2) = 203, (3) = 202}), (4, 3) = Vector(3, {(1) = 161, (2) = 164, (3) = 163}), (4, 4) = Vector(3, {(1) = 121, (2) = 122, (3) = 122}), (4, 5) = Vector(3, {(1) = 82, (2) = 84, (3) = 86}), (4, 6) = Vector(3, {(1) = 49, (2) = 50, (3) = 51})})``

    NULL

    ``

    NULL

    NULL

    ``

     

     

     

     

     

     

     

     

    ``

     

    Corrections to the original version of theis document;
    • Make the scaling for a nonzero black point the same for all RGB color spaces.
    • Clip negative RGB values to zero.
    • Remove the redundant Array container from matrix multiplications.
    Use map in place of the $ to apply a function to each element of an Array.

    Pixel_Conversion_B.mw

     

    The Interactive Embedded Components in Physics are of great importance today and will be even more in the future. Hereand leave a small tutorial of Embedded Components in Physics applied to physics. I hope that somehow you motives to continue the development of science.

     

      Interactive_Embedded_Components_in_Physics.mw      (in spanish)                 

     Ponencia_CRF.pdf

    Atte.

    Lenin Araujo Castillo

    Physics Pure

    Computer Science

     

    To calculate the day of the week for a given date, first of all we need to find out the number of odd days.

    Today I thought of sharing a beautiful problem I learned in my school, though it is easy, it is tricky too.
    Odd Days are number of days more than the complete number of weeks in given period.
    Leap Year is the year which is divisible by 4.
    A normal year has 365 days
    A leap year has 366 days
    One normal year = 365 days = 52weeks + 1day
    One normal year has one odd day

    One leap year = 366 days = 52weeks + 2days
    One leap year has two odd days

    100 years = 76 ordinary years + 24 leap years = 5200 weeks + 124 days = 5217 weeks + 5 days
    100 years have 5 odd days

    400 years have (20+1) 0 odd days

    The number of odd days and the corresponding day of the week is given below

    0-Sunday
    1-Monday
    2-Tuesday
    3-Wednesday
    4-Thursday
    5-Friday
    6-Saturday

    So by finding out the number of odd days you can find out the day of the week. I hope this procedure Will be helpful in solving math problems in exams.

    Thanks.

    The search operation on both questions and posts doesn't work. I get the same set of results for both, and the same results regardless of the search term.

    When I login and then create a question or post and click submit (or preview), I get a new request to login, and, after I do that login, the originally entered message body has been erased.

    We have issued an update to correct a problem a small number of Mac and 64-bit Linux users have experienced when doing certain types of floating point computations on very recent hardware (such as this report on MaplePrimes: http://www.mapleprimes.com/questions/201815-Problem-Loading-MKL-In-Maple-18). When the problem occurs, instead of giving the result, Maple issues a “lost kernel connection” error message and must be restarted.

    While this issue does not occur on most computers, we recommend that all Maple 18 customers running on Mac or 64-bit Linux install this update to ensure they do not encounter this problem. This update can be safely applied to any Mac or 64-bit Linux computer. Windows and 32-bit Linux users do not need, and cannot install, this update.

    To get this update, you can use Tools>Check for Updates from within Maple, or visit Maple 18.01a Downloads.

     

    eithne

    Announcing the 2014 Maple T.A. User Summit

    Maplesoft will be hosting the 2014 Maple T.A. User Summit this October 22-24 in Amsterdam, The Netherlands. This conference discusses important trends in education, how technology is changing, and what all this means for educators and students. This is an opportunity for Maple T.A. users to learn first-hand how Maple T.A. is transforming testing and assessment, and non-users can also benefit by learning about current and future trends in online education.

    Conference highlights include:

    • Expert advice from long term users on how they’re using Maple T.A.
    • Comprehensive hands-on Maple T.A. training
    • Demonstration of new features in Maple T.A., and where the technology is heading
    • Social events with Maplesoft staff and other educators from around the world

    We invite users who are using Maple T.A. in an innovative way in their classroom to submit a presentation proposal by July 15th, 2014. For details, please visit: https://webstore.maplesoft.com/taconference/MapleTA_Summit_CFP.pdf

    For more details, preliminary agenda, and to register, please visit our website: https://webstore.maplesoft.com/taconference/  

    Jonny
    Maplesoft Product Manager, Maple T.A.

    Here in this work and used as the main topic a short description of electrostatics and electrodynamics using the Explore to model the fundamental laws command.

     Corriente_Eléctrica.mw   (in spanish)

     

    Atte.

    L. Araujo C.

     

    Following @acer 's challenge to create some more examples for the Rosetta Code project, I've put together some code that constructs Stem-And-Leaf plots here.

    I've also attached a new mathapp ( StemAndLeafDisplay.mw ) that contains the code as well as an interactive example for Stem-Plots. This MathApp is also viewable online on the MapleCloud here.

    This older post may also be of interest for anyone looking to make a stem and leaf plot with decimals.

    With this contribution we opened a breach in the proper use of the program applied Thermodynamics.

     

    Introducción_a_la_Termodinámica.mw     (in spanish)

     

    Hi,
    The FunctionAdvisor project is currently developing at full speed. During the last two months, a significant amount of new conversion routines and mathematical information for Jacobi elliptic and Jacobi Theta functions, on identities, periodicity, transformations, etc. got added to the conversion network for mathematical functions and to the FunctionAdvisor. The previous months was the turn of the set of complex components, added to the network. Developments regarding the simplification and integration of special functions (e.g SphericalY for computing spherical harmonics or Dirac), as well as fixes to the numerical evaluation of JacobiAM, `assuming` and to differential equation subroutines are also part of the update.

    These developments are available to everybody as usual in the Maplesoft R&D Differential Equations and Mathematical Functions webpage. Below there is a list of the latest developments as seen in the worksheet that comes in the zip with the DEsAndMathematicalFunctions update.

    Edgardo S. Cheb-Terrab
    Physics, Differential Equations and Mathematical Functions, Maplesoft

    The problem is when initializing a Matrix with a list of strings. The worksheet excerpt below shows the normal behavior using a list of integers to initialize a square matrix: the successive list elements fill the matrix by rows.

    Then trying the exact same thing with a list of strings instead of integers gives an error message!
    This is not right. While it is an odd and likely rare problem, it would be better fixed.

    x := [i $ i=1..25];
    [1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25]
    Matrix(5,5,x);
    Matrix(5,5,[1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25]) 

    y := map(convert,x,string);
    ["1", "2", "3", "4", "5", "6", "7", "8", "9", "10", "11", "12", "13", "14", "15", "16", "17", "18", "19", "20", "21", "22", "23", "24", "25"]
    Matrix(5,5,y);
    Error, (in Matrix) initializer defines more columns (25) than column dimension parameter specifies (5)

    Greetings to all.

    As some of you may remember I have posted several announcements concerning Power Group Enumeration and the Polya Enumeration Theorem this past year, e.g. at this MaplePrimes link: Power Group Enumeration.

    I have continued to work in this field and for those of you who have followed the earlier threads I would like to present some links to my more recent work using the Burnside lemma. Of course all of these are programmed in Maple and include the Maple code and it is with the demonstration of Maple's group theory capabilities in mind that I present them to you (math.stackexchange links).

    The third and fourth to last link in particular include advanced Maple code.

    The second entry is new as of October 30 2015.

    With my best wishes for happy group theory computing with Maple,

    Regards,

    Marko Riedel

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