Use sky colormap in old Matlab version

Hello everyone, I want to use colormap "sky" released in Matlab , but my Matlab is an older version. Can someone help give me the parameter to generator this colorbar, or website with source code?

Answer 1

[Chunru]

Copy the following data:

c = sky(256);
for i=1:height(c)
    fprintf("%9.6f   %9.6f   %9.6f\n", c(i, :))
end

 0.900000    0.944700    0.974100
 0.896471    0.942748    0.973186
 0.892941    0.940796    0.972272
 0.889412    0.938845    0.971358
 0.885882    0.936893    0.970444
 0.882353    0.934941    0.969529
 0.878824    0.932989    0.968615
 0.875294    0.931038    0.967701
 0.871765    0.929086    0.966787
 0.868235    0.927134    0.965873
 0.864706    0.925182    0.964959
 0.861176    0.923231    0.964045
 0.857647    0.921279    0.963131
 0.854118    0.919327    0.962216
 0.850588    0.917375    0.961302
 0.847059    0.915424    0.960388
 0.843529    0.913472    0.959474
 0.840000    0.911520    0.958560
 0.836471    0.909568    0.957646
 0.832941    0.907616    0.956732
 0.829412    0.905665    0.955818
 0.825882    0.903713    0.954904
 0.822353    0.901761    0.953989
 0.818824    0.899809    0.953075
 0.815294    0.897858    0.952161
 0.811765    0.895906    0.951247
 0.808235    0.893954    0.950333
 0.804706    0.892002    0.949419
 0.801176    0.890051    0.948505
 0.797647    0.888099    0.947591
 0.794118    0.886147    0.946676
 0.790588    0.884195    0.945762
 0.787059    0.882244    0.944848
 0.783529    0.880292    0.943934
 0.780000    0.878340    0.943020
 0.776471    0.876388    0.942106
 0.772941    0.874436    0.941192
 0.769412    0.872485    0.940278
 0.765882    0.870533    0.939364
 0.762353    0.868581    0.938449
 0.758824    0.866629    0.937535
 0.755294    0.864678    0.936621
 0.751765    0.862726    0.935707
 0.748235    0.860774    0.934793
 0.744706    0.858822    0.933879
 0.741176    0.856871    0.932965
 0.737647    0.854919    0.932051
 0.734118    0.852967    0.931136
 0.730588    0.851015    0.930222
 0.727059    0.849064    0.929308
 0.723529    0.847112    0.928394
 0.720000    0.845160    0.927480
 0.716471    0.843208    0.926566
 0.712941    0.841256    0.925652
 0.709412    0.839305    0.924738
 0.705882    0.837353    0.923824
 0.702353    0.835401    0.922909
 0.698824    0.833449    0.921995
 0.695294    0.831498    0.921081
 0.691765    0.829546    0.920167
 0.688235    0.827594    0.919253
 0.684706    0.825642    0.918339
 0.681176    0.823691    0.917425
 0.677647    0.821739    0.916511
 0.674118    0.819787    0.915596
 0.670588    0.817835    0.914682
 0.667059    0.815884    0.913768
 0.663529    0.813932    0.912854
 0.660000    0.811980    0.911940
 0.656471    0.810028    0.911026
 0.652941    0.808076    0.910112
 0.649412    0.806125    0.909198
 0.645882    0.804173    0.908284
 0.642353    0.802221    0.907369
 0.638824    0.800269    0.906455
 0.635294    0.798318    0.905541
 0.631765    0.796366    0.904627
 0.628235    0.794414    0.903713
 0.624706    0.792462    0.902799
 0.621176    0.790511    0.901885
 0.617647    0.788559    0.900971
 0.614118    0.786607    0.900056
 0.610588    0.784655    0.899142
 0.607059    0.782704    0.898228
 0.603529    0.780752    0.897314
 0.600000    0.778800    0.896400
 0.596471    0.776848    0.895486
 0.592941    0.774896    0.894572
 0.589412    0.772945    0.893658
 0.585882    0.770993    0.892744
 0.582353    0.769041    0.891829
 0.578824    0.767089    0.890915
 0.575294    0.765138    0.890001
 0.571765    0.763186    0.889087
 0.568235    0.761234    0.888173
 0.564706    0.759282    0.887259
 0.561176    0.757331    0.886345
 0.557647    0.755379    0.885431
 0.554118    0.753427    0.884516
 0.550588    0.751475    0.883602
 0.547059    0.749524    0.882688
 0.543529    0.747572    0.881774
 0.540000    0.745620    0.880860
 0.536471    0.743668    0.879946
 0.532941    0.741716    0.879032
 0.529412    0.739765    0.878118
 0.525882    0.737813    0.877204
 0.522353    0.735861    0.876289
 0.518824    0.733909    0.875375
 0.515294    0.731958    0.874461
 0.511765    0.730006    0.873547
 0.508235    0.728054    0.872633
 0.504706    0.726102    0.871719
 0.501176    0.724151    0.870805
 0.497647    0.722199    0.869891
 0.494118    0.720247    0.868976
 0.490588    0.718295    0.868062
 0.487059    0.716344    0.867148
 0.483529    0.714392    0.866234
 0.480000    0.712440    0.865320
 0.476471    0.710488    0.864406
 0.472941    0.708536    0.863492
 0.469412    0.706585    0.862578
 0.465882    0.704633    0.861664
 0.462353    0.702681    0.860749
 0.458824    0.700729    0.859835
 0.455294    0.698778    0.858921
 0.451765    0.696826    0.858007
 0.448235    0.694874    0.857093
 0.444706    0.692922    0.856179
 0.441176    0.690971    0.855265
 0.437647    0.689019    0.854351
 0.434118    0.687067    0.853436
 0.430588    0.685115    0.852522
 0.427059    0.683164    0.851608
 0.423529    0.681212    0.850694
 0.420000    0.679260    0.849780
 0.416471    0.677308    0.848866
 0.412941    0.675356    0.847952
 0.409412    0.673405    0.847038
 0.405882    0.671453    0.846124
 0.402353    0.669501    0.845209
 0.398824    0.667549    0.844295
 0.395294    0.665598    0.843381
 0.391765    0.663646    0.842467
 0.388235    0.661694    0.841553
 0.384706    0.659742    0.840639
 0.381176    0.657791    0.839725
 0.377647    0.655839    0.838811
 0.374118    0.653887    0.837896
 0.370588    0.651935    0.836982
 0.367059    0.649984    0.836068
 0.363529    0.648032    0.835154
 0.360000    0.646080    0.834240
 0.356471    0.644128    0.833326
 0.352941    0.642176    0.832412
 0.349412    0.640225    0.831498
 0.345882    0.638273    0.830584
 0.342353    0.636321    0.829669
 0.338824    0.634369    0.828755
 0.335294    0.632418    0.827841
 0.331765    0.630466    0.826927
 0.328235    0.628514    0.826013
 0.324706    0.626562    0.825099
 0.321176    0.624611    0.824185
 0.317647    0.622659    0.823271
 0.314118    0.620707    0.822356
 0.310588    0.618755    0.821442
 0.307059    0.616804    0.820528
 0.303529    0.614852    0.819614
 0.300000    0.612900    0.818700
 0.296471    0.610948    0.817786
 0.292941    0.608996    0.816872
 0.289412    0.607045    0.815958
 0.285882    0.605093    0.815044
 0.282353    0.603141    0.814129
 0.278824    0.601189    0.813215
 0.275294    0.599238    0.812301
 0.271765    0.597286    0.811387
 0.268235    0.595334    0.810473
 0.264706    0.593382    0.809559
 0.261176    0.591431    0.808645
 0.257647    0.589479    0.807731
 0.254118    0.587527    0.806816
 0.250588    0.585575    0.805902
 0.247059    0.583624    0.804988
 0.243529    0.581672    0.804074
 0.240000    0.579720    0.803160
 0.236471    0.577768    0.802246
 0.232941    0.575816    0.801332
 0.229412    0.573865    0.800418
 0.225882    0.571913    0.799504
 0.222353    0.569961    0.798589
 0.218824    0.568009    0.797675
 0.215294    0.566058    0.796761
 0.211765    0.564106    0.795847
 0.208235    0.562154    0.794933
 0.204706    0.560202    0.794019
 0.201176    0.558251    0.793105
 0.197647    0.556299    0.792191
 0.194118    0.554347    0.791276
 0.190588    0.552395    0.790362
 0.187059    0.550444    0.789448
 0.183529    0.548492    0.788534
 0.180000    0.546540    0.787620
 0.176471    0.544588    0.786706
 0.172941    0.542636    0.785792
 0.169412    0.540685    0.784878
 0.165882    0.538733    0.783964
 0.162353    0.536781    0.783049
 0.158824    0.534829    0.782135
 0.155294    0.532878    0.781221
 0.151765    0.530926    0.780307
 0.148235    0.528974    0.779393
 0.144706    0.527022    0.778479
 0.141176    0.525071    0.777565
 0.137647    0.523119    0.776651
 0.134118    0.521167    0.775736
 0.130588    0.519215    0.774822
 0.127059    0.517264    0.773908
 0.123529    0.515312    0.772994
 0.120000    0.513360    0.772080
 0.116471    0.511408    0.771166
 0.112941    0.509456    0.770252
 0.109412    0.507505    0.769338
 0.105882    0.505553    0.768424
 0.102353    0.503601    0.767509
 0.098824    0.501649    0.766595
 0.095294    0.499698    0.765681
 0.091765    0.497746    0.764767
 0.088235    0.495794    0.763853
 0.084706    0.493842    0.762939
 0.081176    0.491891    0.762025
 0.077647    0.489939    0.761111
 0.074118    0.487987    0.760196
 0.070588    0.486035    0.759282
 0.067059    0.484084    0.758368
 0.063529    0.482132    0.757454
 0.060000    0.480180    0.756540
 0.056471    0.478228    0.755626
 0.052941    0.476276    0.754712
 0.049412    0.474325    0.753798
 0.045882    0.472373    0.752884
 0.042353    0.470421    0.751969
 0.038824    0.468469    0.751055
 0.035294    0.466518    0.750141
 0.031765    0.464566    0.749227
 0.028235    0.462614    0.748313
 0.024706    0.460662    0.747399
 0.021176    0.458711    0.746485
 0.017647    0.456759    0.745571
 0.014118    0.454807    0.744656
 0.010588    0.452855    0.743742
 0.007059    0.450904    0.742828
 0.003529    0.448952    0.741914
 0.000000    0.447000    0.741000

[Chunru]

The source code for sky:

EDIT: COPYRIGHT code removed.

To generate the colormap without sky:

lightColorOrder = matlab.graphics.internal.colorOrderValues('gem');
% You need the following 3 numbers if the above is not in your version
baseColor = lightColorOrder(1, :)

Sky colormap without sky function:

baseColor = [0 0.4470 0.7410]
m = 256;
v = linspace(0.1, 1, m)';
map = baseColor.*v + (1-v);

mesh(peaks(25));
colormap(map);
colorbar

[Walter Roberson]

I abstracted the official function and simplified the math slightly to produce my Answer. I suspect that older versions do not have the internal routine used here.

[Ziwen Gu]

Thanks , it works well :)

Answer 2

[Walter Roberson]

Generation:

C = [0, 447/1000, 741/1000];

now for any fraction F between .1 and 1,

1-(1-baseColor)*F

subdivide the range .1 to 1 by as many steps as you want in the color map.

[Ziwen Gu]

Grateful for your help! Both of your answers work well