我已经经历过这个问题正确选择表中坐标值和元值的分配可以大大提高编译速度pgfplots。lua backend所以我只想问一下，是否有人看到可以加快速度的东西，主要是在颜色图转换中？
对于此代码的编译，lua backend根据日志，也被禁用，并显示消息：Package pgfplots info on input line 97: Using 'lua backend=false' for axis: x coord trafo unsupported.。可以通过更改代码或颜色条轴转换的代码来避免这种情况吗point meta，例如通过使用一些 lua 代码？
我的主要问题是编译时间（即使我将图像外部化）。对于分辨率不令人满意的输入数据文件（.txt 文件大约有 300 kB），编译时间略长于 3 分钟。采样率加倍后，输入文件的大小大约是原来的四倍，编译时间增加了十六倍，即将近 1 小时。（4²=16，这与手册中pgfplots对大型数据集二次复杂度的陈述一致）这种复杂性来自哪里？仅仅是数据量，还是将输入文件分成几个文件会更好？
仅坐标变换代码：
\pgfplotsset{
symlog colormap trafo/.code={
\pgfkeysalso{%
y coord trafo/.code={%
\pgfmathparse{##1>#1 ? 1+3*ln(##1<#1?1: (##1/#1))/ln(10*sqrt(10)) : (##1<-#1 ? -1-3*ln(##1>-#1?1: (-##1/#1))/ln(10*sqrt(10)) : ##1/#1)}
},
y coord inv trafo/.code={%
\pgfmathparse{##1>1 ? exp((##1-1)/3*ln(10*sqrt(10)))*#1 : (##1<-1 ? -exp((-##1-1)/3*ln(10*sqrt(10)))*#1 : ##1*#1)}
},
}%
},
symlog colormap/.code n args={3}{
\pgfkeysalso{
colorbar style={
symlog colormap trafo={#1},
point meta min={#2},
point meta max={#3},
},
point meta={z>#1 ? 1+3*ln(z<#1?1: (z/#1))/ln(10*sqrt(10)) : (z<-#1 ? -1-3*ln(z>-#1?1: (-z/#1))/ln(10*sqrt(10)) : z/#1)},
}%
},
}
完整示例
\documentclass{article}
\usepackage{xfrac}
\def\infile{infile.txt}
\usepackage{pgfplots}
\usepackage{pgfplotstable}
\pgfplotsset{compat=newest}
\pgfplotsset{
symlog colormap trafo/.code={
\pgfkeysalso{%
y coord trafo/.code={%
\pgfmathparse{##1>#1 ? 1+3*ln(##1<#1?1: (##1/#1))/ln(10*sqrt(10)) : (##1<-#1 ? -1-3*ln(##1>-#1?1: (-##1/#1))/ln(10*sqrt(10)) : ##1/#1)}
},
y coord inv trafo/.code={%
\pgfmathparse{##1>1 ? exp((##1-1)/3*ln(10*sqrt(10)))*#1 : (##1<-1 ? -exp((-##1-1)/3*ln(10*sqrt(10)))*#1 : ##1*#1)}
},
}%
},
symlog colormap/.code n args={3}{
\pgfkeysalso{
colorbar style={
symlog colormap trafo={#1},
point meta min={#2},
point meta max={#3},
},
point meta={z>#1 ? 1+3*ln(z<#1?1: (z/#1))/ln(10*sqrt(10)) : (z<-#1 ? -1-3*ln(z>-#1?1: (-z/#1))/ln(10*sqrt(10)) : z/#1)},
}%
},
}
\begin{document}
\thispagestyle{empty}
\begin{tikzpicture}
\begin{axis}[axis equal image,
xmin=-8,
z buffer = sort,
xmax=8,
ymin=0,
ymax=10,
grid=major,
axis on top,
colorbar,
symlog colormap={142.3}{-4500}{4500},
colormap/viridis,
mesh/ordering=y varies,
view={0}{90},
colorbar style={
scaled ticks=false,
ytick={-4501,-1423,-450,-142.3,0,142.3,450,1423,4501},
yticklabel={
\pgfmathparse{\tick/100}\pgfmathprintnumber[fixed relative, precision=2]{\pgfmathresult}
},
yticklabel style={
align=right,
text width = 1.875em,
},
xlabel = {$E_z \textrm{ in kV/m}$},
xlabel style = {xshift = 0.35cm, yshift = -0.4625 cm},
},
tick label style={/pgf/number format/fixed},
enlargelimits=false,
xlabel={$x \textrm{ in mm}$},
ylabel={$y \textrm{ in mm}$},
]
\pgfplotstableset{skip first n=2}
\pgfplotstableread{\infile}\datatable
\addplot3[
mesh/rows=65,
surf,
shader = interp,
] table [
x index = 0,
y index= 1,
z index = 2;
] from \datatable {};
\end{axis}
\end{tikzpicture}
\end{document}
示例文件（截断）
x [mm] 0
-----------------------------------------------------------------------------------------------------------------------------------------
-8 0 51.0614
-7.75 0 82.8847
-7.5 0 63.4588
-7.25 0 53.413
-7 0 45.8015
-6.75 0 38.6945
-6.5 0 31.5657
-6.25 0 24.3476
-6 0 17.1636
-5.75 0 10.2049
-5.5 0 3.6868
-5.25 0 -2.17792
-5 0 -7.18864
-4.75 0 -11.1697
-4.5 0 -13.9803
-4.25 0 -15.5134
-4 0 -15.7146
-3.75 0 -14.5676
-3.5 0 -12.1229
-3.25 0 -8.48218
-3 0 -3.81099
-2.75 0 1.55382
-2.5 0 7.13892
-2.25 0 12.0255
-2 0 14.4733
-1.75 0 10.3511
-1.5 0 -56.9732
-1.25 0 -57.9164
-1 0 -21.3907
-0.75 0 93.6603
-0.5 0 512.283
-0.25 0 1778.09
0 0 1881.37
0.25 0 1778.09
0.5 0 512.281
0.75 0 93.658
1 0 -21.3938
1.25 0 -57.92
1.5 0 -56.9765
1.75 0 10.3483
2 0 14.4687
2.25 0 12.0195
2.5 0 7.13207
2.75 0 1.54623
3 0 -3.81901
3.25 0 -8.49036
3.5 0 -12.131
3.75 0 -14.5755
4 0 -15.7219
4.25 0 -15.5201
4.5 0 -13.9861
4.75 0 -11.1745
5 0 -7.19197
5.25 0 -2.17986
5.5 0 3.68637
5.75 0 10.2064
6 0 17.1669
6.25 0 24.3528
6.5 0 31.5727
6.75 0 38.7035
7 0 45.8125
7.25 0 53.4264
7.5 0 63.4758
7.75 0 82.9077
8 0 51.0745
-8 0.25 48.8507
-7.75 0.25 71.4631
-7.5 0.25 51.8272
-7.25 0.25 42.4871
-7 0.25 36.1465
-6.75 0.25 30.5903
-6.5 0.25 25.1597
-6.25 0.25 19.6837
-6 0.25 14.2034
-5.75 0.25 8.83354
-5.5 0.25 3.71559
-5.25 0.25 -1.00413
-5 0.25 -5.18482
-4.75 0.25 -8.69938
-4.5 0.25 -11.4425
-4.25 0.25 -13.3293
-4 0.25 -14.3084
-3.75 0.25 -14.3513
-3.5 0.25 -13.4718
-3.25 0.25 -11.714
-3 0.25 -9.15892
-2.75 0.25 -6.01235
-2.5 0.25 -2.57951
-2.25 0.25 0.450236
-2 0.25 1.43912
-1.75 0.25 -4.83268
-1.5 0.25 -42.3624
-1.25 0.25 -38.0751
-1 0.25 16.1594
-0.75 0.25 178.537
-0.5 0.25 748.531
-0.25 0.25 2461.65
0 0.25 2601.04
0.25 0.25 2461.65
0.5 0.25 748.53
0.75 0.25 178.535
1 0.25 16.1563
1.25 0.25 -38.0789
1.5 0.25 -42.366
1.75 0.25 -4.83578
2 0.25 1.43538
2.25 0.25 0.445735
2.5 0.25 -2.58454
2.75 0.25 -6.01804
3 0.25 -9.16484
3.25 0.25 -11.7201
3.5 0.25 -13.478
3.75 0.25 -14.3574
4 0.25 -14.314
4.25 0.25 -13.3345
4.5 0.25 -11.4472
4.75 0.25 -8.70337
5 0.25 -5.1878
5.25 0.25 -1.0061
5.5 0.25 3.71481
5.75 0.25 8.83392
6 0.25 14.2051
6.25 0.25 19.6867
6.5 0.25 25.1642
6.75 0.25 30.5962
7 0.25 36.154
7.25 0.25 42.4966
7.5 0.25 51.8396
7.75 0.25 71.4815
8 0.25 48.8619
-8 0.5 48.7844
-7.75 0.5 67.6708
-7.5 0.5 47.0852
-7.25 0.5 37.682
-7 0.5 31.6811
-6.75 0.5 26.659
-6.5 0.5 21.8645
-6.25 0.5 17.0579
-6 0.5 12.2321
-5.75 0.5 7.45987
-5.5 0.5 2.84438
-5.25 0.5 -1.50177
-5 0.5 -5.46699
-4.75 0.5 -8.94756
-4.5 0.5 -11.8542
-4.25 0.5 -14.1114
-4 0.5 -15.6659
-3.75 0.5 -16.4791
-3.5 0.5 -16.5394
-3.25 0.5 -15.8496
-3 0.5 -14.4255
-2.75 0.5 -12.3673
-2.5 0.5 -9.79737
-2.25 0.5 -6.98801
-2 0.5 -4.6393
-1.75 0.5 -4.80819
-1.5 0.5 -11.6809
-1.25 0.5 8.14997
-1 0.5 78.3415
-0.75 0.5 274.749
-0.5 0.5 943.2
-0.25 0.5 2944.76
0 0.5 3107.5
0.25 0.5 2944.76
0.5 0.5 943.199
0.75 0.5 274.747
1 0.5 78.3391
1.25 0.5 8.14696
1.5 0.5 -11.6839
1.75 0.5 -4.8112
2 0.5 -4.64255
2.25 0.5 -6.99184
2.5 0.5 -9.80156
2.75 0.5 -12.3719
3 0.5 -14.4304
3.25 0.5 -15.8547
3.5 0.5 -16.5445
3.75 0.5 -16.4843
4 0.5 -15.671
4.25 0.5 -14.1161
4.5 0.5 -11.8587
4.75 0.5 -8.95129
5 0.5 -5.47007
5.25 0.5 -1.50406
5.5 0.5 2.84302
5.75 0.5 7.45941
6 0.5 12.2327
6.25 0.5 17.0596
6.5 0.5 21.8673
6.75 0.5 26.6631
7 0.5 31.6865
7.25 0.5 37.6891
7.5 0.5 47.095
7.75 0.5 67.6869
8 0.5 48.7944
-8 0.75 49.6667
-7.75 0.75 67.5706
-7.5 0.75 45.782
-7.25 0.75 35.9227
-7 0.75 29.7622
-6.75 0.75 24.7203
-6.5 0.75 19.9793
-6.25 0.75 15.2548
-6 0.75 10.5115
-5.75 0.75 5.80032
-5.5 0.75 1.2061
-5.25 0.75 -3.17377
-5 0.75 -7.24051
-4.75 0.75 -10.9001
-4.5 0.75 -14.0696
-4.25 0.75 -16.6759
-4 0.75 -18.6636
-3.75 0.75 -19.9861
-3.5 0.75 -20.6155
-3.25 0.75 -20.5269
-3 0.75 -19.6867
-2.75 0.75 -18.1148
-2.5 0.75 -15.773
-2.25 0.75 -12.5353
-2 0.75 -8.19302
-1.75 0.75 -1.85639
-1.5 0.75 10.4672
-1.25 0.75 42.7128
-1 0.75 122.477
-0.75 0.75 336.302
-0.5 0.75 1052.96
-0.25 0.75 3198.01
0 0.75 3372.36
0.25 0.75 3198.01
0.5 0.75 1052.96
0.75 0.75 336.301
1 0.75 122.475
1.25 0.75 42.7104
1.5 0.75 10.4648
1.75 0.75 -1.85915
2 0.75 -8.19592
2.25 0.75 -12.5388
2.5 0.75 -15.7768
2.75 0.75 -18.1191
3 0.75 -19.6913
3.25 0.75 -20.5316
3.5 0.75 -20.6203
3.75 0.75 -19.991
4 0.75 -18.6684
4.25 0.75 -16.6806
4.5 0.75 -14.0739
4.75 0.75 -10.904
5 0.75 -7.24377
5.25 0.75 -3.17647
5.5 0.75 1.20418
5.75 0.75 5.79908
6 0.75 10.5113
6.25 0.75 15.2555
6.5 0.75 19.9811
6.75 0.75 24.7232
7 0.75 29.7664
7.25 0.75 35.9284
7.5 0.75 45.7904
7.75 0.75 67.5843
8 0.75 49.6757
-8 1 50.6639
-7.75 1 68.5314
-7.5 1 45.5971
-7.25 1 35.1523
-7 1 28.632
-6.75 1 23.3348
-6.5 1 18.395
-6.25 1 13.498
-6 1 8.59186
-5.75 1 3.71581
-5.5 1 -1.05397
-5.25 1 -5.6273
-5 1 -9.91064
-4.75 1 -13.8143
-4.5 1 -17.2579
-4.25 1 -20.1693
-4 1 -22.492
-3.75 1 -24.1753
-3.5 1 -25.1828
-3.25 1 -25.4734
-3 1 -24.9818
-2.75 1 -23.6741
-2.5 1 -21.4015
-2.25 1 -17.7821
-2 1 -12.1512
-1.75 1 -2.75656
-1.5 1 14.6518
-1.25 1 50.5191
-1 1 131.565
-0.75 1 345.117
-0.5 1 1059.9
-0.25 1 3203.64
0 1 3377.83
0.25 1 3203.65
0.5 1 1059.9
0.75 1 345.115
1 1 131.564
1.25 1 50.5172
1.5 1 14.6496
1.75 1 -2.75902
2 1 -12.1539
2.25 1 -17.7854
2.5 1 -21.405
2.75 1 -23.6781
3 1 -24.9861
3.25 1 -25.478
3.5 1 -25.1876
3.75 1 -24.1801
4 1 -22.4967
4.25 1 -20.174
4.5 1 -17.2624
4.75 1 -13.8185
5 1 -9.91432
5.25 1 -5.63034
5.5 1 -1.05653
5.75 1 3.71403
6 1 8.59102
6.25 1 13.4979
6.5 1 18.3959
6.75 1 23.3367
7 1 28.6351
7.25 1 35.1571
7.5 1 45.6044
7.75 1 68.5438
8 1 50.6719
-8 1.25 51.3174
-7.75 1.25 69.3629
-7.5 1.25 45.4568
-7.25 1.25 34.4408
-7 1.25 27.512
-6.75 1.25 21.8823
-6.5 1.25 16.6537
-6.25 1.25 11.4921
-6 1.25 6.33623
-5.75 1.25 1.21921
-5.5 1.25 -3.78699
-5.25 1.25 -8.59521
-5 1.25 -13.1147
-4.75 1.25 -17.2581
-4.5 1.25 -20.9464
-4.25 1.25 -24.1099
-4 1.25 -26.6934
-3.75 1.25 -28.6475
-3.5 1.25 -29.9355
-3.25 1.25 -30.5137
-3 1.25 -30.3075
-2.75 1.25 -29.2648
-2.5 1.25 -27.1978
-2.25 1.25 -23.647
-2 1.25 -17.8619
-1.75 1.25 -8.08802
-1.5 1.25 9.40737
-1.25 1.25 43.5587
-1 1.25 118.623
-0.75 1.25 315.05
-0.5 1.25 972.254
-0.25 1.25 2944.29
0 1.25 3104.61
0.25 1.25 2944.29
0.5 1.25 972.252
0.75 1.25 315.049
1 1.25 118.622
1.25 1.25 43.5572
1.5 1.25 9.4056
1.75 1.25 -8.09007
2 1.25 -17.8643
2.25 1.25 -23.6499
2.5 1.25 -27.2009
2.75 1.25 -29.2685
3 1.25 -30.3117
3.25 1.25 -30.518
3.5 1.25 -29.9403
3.75 1.25 -28.6524
4 1.25 -26.6983
4.25 1.25 -24.1148
4.5 1.25 -20.9512
4.75 1.25 -17.2625
5 1.25 -13.1189
5.25 1.25 -8.59896
5.5 1.25 -3.79004
5.75 1.25 1.21679
6 1.25 6.33456
6.25 1.25 11.4913
6.5 1.25 16.6538
6.75 1.25 21.8834
7 1.25 27.5144
7.25 1.25 34.4446
7.5 1.25 45.463
7.75 1.25 69.3739
8 1.25 51.3245
-8 1.5 51.2722
-7.75 1.5 69.3806
-7.5 1.5 44.8177
-7.25 1.5 33.3384
-7 1.5 26.0324
-6.75 1.5 20.0701
-6.5 1.5 14.5394
-6.25 1.5 9.0976
-6 1.5 3.68028
-5.75 1.5 -1.68137
-5.5 1.5 -6.91641
-5.25 1.5 -11.9388
-5 1.5 -16.6587
-4.75 1.5 -20.9906
-4.5 1.5 -24.8586
-4.25 1.5 -28.1963
-4 1.5 -30.9547
-3.75 1.5 -33.0928
-3.5 1.5 -34.5847
-3.25 1.5 -35.4024
-3 1.5 -35.4942
-2.75 1.5 -34.8323
-2.5 1.5 -33.2706
-2.25 1.5 -30.4296
-2 1.5 -25.6859
-1.75 1.5 -17.5932
-1.5 1.5 -3.12652
-1.25 1.5 24.96
-1 1.5 86.4887
-0.75 1.5 247.128
-0.5 1.5 783.513
-0.25 1.5 2391.2
0 1.5 2522.36
0.25 1.5 2391.21
0.5 1.5 783.511
0.75 1.5 247.128
1 1.5 86.4884
1.25 1.5 24.959
1.5 1.5 -3.12774
1.75 1.5 -17.5947
2 1.5 -25.6879
2.25 1.5 -30.4323
2.5 1.5 -33.2736
2.75 1.5 -34.8358
3 1.5 -35.4981
3.25 1.5 -35.4066
3.5 1.5 -34.5893
3.75 1.5 -33.0976
4 1.5 -30.9597
4.25 1.5 -28.2014
4.5 1.5 -24.8636
4.75 1.5 -20.9955
5 1.5 -16.6633
5.25 1.5 -11.943
5.5 1.5 -6.92009
5.75 1.5 -1.6845
6 1.5 3.67791
6.25 1.5 9.09602
6.5 1.5 14.5387
6.75 1.5 20.0704
7 1.5 26.0338
7.25 1.5 33.3413
7.5 1.5 44.8228
7.75 1.5 69.39
8 1.5 51.2781
答案1
如果您不必每次都编译这部分，您可以创建一个 pdf 文件并通过 includegraphics 包含它....只是一个想法......
答案2
我找到了一种可以大大减少时间的方法。正如 pfgplots 手册中提到的那样，如何加载数据非常重要。使用文件名加载表格
\addplot3[
mesh/rows=65,
surf,
shader = interp,
] table [
x index = 0,
y index= 1,
z index = 2;
] {\infile}; % \infile just contains the filename, not a table
而不是基于宏的预加载表
\pgfplotstableread{\infile}\datatable
\addplot3[
mesh/rows=65,
surf,
shader = interp,
] table [
x index = 0,
y index= 1,
z index = 2;
] from \datatable {};
将 500kB 输入文件（约 26k 行）的编译时间从 363 秒（6 分钟）显著缩短至 42 秒。当然，由于文件大小的原因，最好在之后将生成的 pdf 转换为 png。