这里有一堆实现供您进行基准测试（都是纯 MATLAB）。他们中的一些人借鉴了其他解决方案的想法。
function M = func_eval_strjoin(C)
M = eval(['[' strjoin(strrep(C,'_',' ').',';') ']']);
end
function M = func_eval_sprintf(C)
C = strrep(C,'_',' ');
M = eval(['[' sprintf('%s;',C{:}) ']']);
end
function M = func_eval_cellfun(C)
M = cell2mat(cellfun(@eval, strcat('[',strrep(C,'_',' '),']'), 'Uniform',false));
end
function M = func_eval_loop(C)
M = zeros(numel(C),nnz(C{1}=='_')+1);
for i=1:numel(C)
M(i,:) = eval(['[' strrep(C{i},'_',' ') ']']);
end
end
function M = func_str2num_strjoin(C)
M = reshape(str2num(strjoin(strrep(C.','_',' '))), [], numel(C)).';
end
function M = func_str2num_sprintf(C)
C = strrep(C,'_',' ');
M = reshape(str2num(sprintf('%s ',C{:})), [], numel(C)).';
end
function M = func_str2num_cellfun(C)
M = cell2mat(cellfun(@str2num, strrep(C, '_', ' '), 'Uniform',false));
end
function M = func_str2num_loop(C)
M = zeros(numel(C),nnz(C{1}=='_')+1);
for i=1:numel(C)
M(i,:) = str2num(strrep(C{i}, '_', ' '));
end
end
function M = func_sscanf_strjoin(C)
M = reshape(sscanf(strjoin(C', '_'), '%f_'), [], numel(C)).';
end
function M = func_sscanf_sprintf(C)
M = reshape(sscanf(sprintf('%s_',C{:}),'%f_'), [], numel(C)).';
end
function M = func_sscanf_cellfun(C)
M = cell2mat(cellfun(@(c) sscanf(c, '%f_'), C, 'Uniform',false).').';
end
function M = func_sscanf_loop(C)
M = zeros(numel(C),nnz(C{1}=='_')+1);
for i=1:numel(C)
M(i,:) = sscanf(C{i}, '%f_');
end
end
function M = func_textscan_strjoin(C)
M = textscan(strjoin(C', '_'), '%.0f', 'Delimiter','_');
M = reshape(M{1}, [], numel(C)).';
end
function M = func_textscan_sprintf(C)
M = textscan(sprintf('%s_',C{:}),'%.0f', 'Delimiter','_');
M = reshape(M{1}, [], numel(C)).';
end
function M = func_textscan_cellfun(C)
M = cell2mat(cellfun(@(str) textscan(str, '%.0f', 'Delimiter','_'), C).').';
end
function M = func_textscan_loop(C)
M = zeros(numel(C),nnz(C{1}=='_')+1);
for i=1:numel(C)
x = textscan(C{i}, '%.0f', 'Delimiter','_');
M(i,:) = x{1};
end
end
function M = func_str2double_strsplit_strjoin(C)
M = reshape(str2double(strsplit(strjoin(C','_'),'_')), [], numel(C)).';
end
function M = func_str2double_strsplit_sprintf(C)
M = strsplit(sprintf('%s_',C{:}), '_');
M = reshape(str2double(M(1:end-1)), [], numel(C)).';
end
function M = func_str2double_strsplit(C)
M = cellfun(@(c) strsplit(c,'_'), C, 'Uniform',false);
M = str2double(cat(1,M{:}));
end
function M = func_str2double_strsplit_cellfun(C)
M = cell2mat(cellfun(@(c) str2double(strsplit(c,'_')), C, 'Uniform',false));
end
function M = func_str2double_strsplit_loop(C)
M = zeros(numel(C),nnz(C{1}=='_')+1);
for i=1:numel(C)
M(i,:) = str2double(strsplit(C{i},'_'));
end
end
function M = func_str2double_regex_split_strjoin(C)
M = reshape(str2double(regexp(strjoin(C.','_'), '_', 'split')), [], numel(C)).';
end
function M = func_str2double_regex_split_sprintf(C)
M = regexp(sprintf('%s_',C{:}), '_', 'split');
M = reshape(str2double(M(1:end-1)), [], numel(C)).';
end
function M = func_str2double_regex_split(C)
M = regexp(C, '_', 'split');
M = reshape(str2double([M{:}]), [], numel(C)).';
end
function M = func_str2double_regex_split_cellfun(C)
M = cell2mat(cellfun(@str2double, regexp(C, '_', 'split'), 'Uniform',false));
end
function M = func_str2double_regex_split_loop(C)
M = zeros(numel(C),nnz(C{1}=='_')+1);
for i=1:numel(C)
M(i,:) = str2double(regexp(C{i}, '_', 'split'));
end
end
function M = func_str2double_regex_tokens_strjoin_1(C)
M = reshape(cellfun(@str2double, regexp(strjoin(C.','_'), '(\d+)', 'tokens')), [], numel(C)).';
end
function M = func_str2double_regex_tokens_strjoin_2(C)
M = regexp(strjoin(C.','_'), '(\d+)', 'tokens');
M = reshape(str2double([M{:}]), [], numel(C)).';
end
function M = func_str2double_regex_tokens_sprintf_1(C)
M = reshape(cellfun(@str2double, regexp(sprintf('%s_',C{:}), '(\d+)', 'tokens')), [], numel(C)).';
end
function M = func_str2double_regex_tokens_sprintf_2(C)
M = regexp(sprintf('%s_',C{:}), '(\d+)', 'tokens');
M = reshape(str2double([M{:}]), [], numel(C)).';
end
function M = func_str2double_regex_tokens(C)
M = regexp(C, '(\d+)', 'tokens');
M = cat(1,M{:});
M = reshape(str2double([M{:}]), size(M));
end
function M = func_str2double_regex_tokens_cellfun(C)
M = regexp(C, '(\d+)', 'tokens');
M = cellfun(@str2double, cat(1,M{:}));
end
function M = func_str2double_regex_tokens_loop(C)
M = zeros(numel(C),nnz(C{1}=='_')+1);
for i=1:numel(C)
x = regexp(C{i}, '(\d+)', 'tokens');
M(i,:) = str2double([x{:}]);
end
end
大多数方法都是相同想法的变体，只是实现方式略有不同（例如：使用显式 for 循环与cellfun，使用strjoin 与sprintf 将字符串单元数组连接成一个字符串等..)。
让我再分解一下：
有基于eval 的解决方案。我们要么在循环中应用eval，要么在将字符串拼合为一个之后进行一次调用。
同样有基于调用str2num 的解决方案（在用空格替换下划线之后）。值得注意的是str2num本身在内部调用eval。
还有sscanf 和textscan 解决方案。像以前一样，我们要么在循环中使用它们，要么调用一个长字符串。
另一组解决方案基于在用下划线分隔符分割字符串后调用str2double。还有其他拆分字符串的方法（使用带有“split”选项的regex，或使用strsplit 函数）。
终于有了一套基于正则表达式匹配的解决方案。
编辑：
我创建了一组函数来对各种实现进行基准测试 (GitHub Gist)。这是pre-packaged files，到目前为止已发布了所有解决方案。我包含了已编译的 MEX 函数（适用于 64 位 Windows）以及 MinGW-w64 DLL 依赖项。
这是在我的机器上运行的结果（四核 Intel Core i7 CPU、8GB、Win8.1、MATLAB R2014a 的笔记本电脑）。我测试了以下尺寸：10x10、100x10、1000x10 和 10000x10。如您所见，随着数据量的增加，MEX 解决方案的效果会更好...
编辑#2：
根据要求，我用最新的解决方案更新了我的测试结果；我添加了 @chappjc 的 MEX 文件的修改版本，以及 @Divakar 的 GPU 版本。这是文件的updated archive。
我使用与以前相同的机器。我已将单元阵列大小增加到 1e5。我的 GPU 设备非常适合笔记本电脑：
>> gpuDevice
ans =
CUDADevice with properties:
Name: 'GeForce GT 630M'
Index: 1
ComputeCapability: '2.1'
SupportsDouble: 1
DriverVersion: 5.5000
ToolkitVersion: 5.5000
MaxThreadsPerBlock: 1024
MaxShmemPerBlock: 49152
MaxThreadBlockSize: [1024 1024 64]
MaxGridSize: [65535 65535 65535]
SIMDWidth: 32
TotalMemory: 2.1475e+09
FreeMemory: 2.0453e+09
MultiprocessorCount: 2
ClockRateKHz: 950000
ComputeMode: 'Default'
GPUOverlapsTransfers: 1
KernelExecutionTimeout: 1
CanMapHostMemory: 1
DeviceSupported: 1
DeviceSelected: 1
以下是最新结果：
>> t
t =
func nrows ncols time
________________________________________ _____ _____ __________
'func_eval_cellfun' 10 10 0.00044645
'func_eval_loop' 10 10 0.0001554
'func_eval_sprintf' 10 10 7.6547e-05
'func_eval_strjoin' 10 10 0.00056739
'func_sscanf_cellfun' 10 10 0.00037247
'func_sscanf_loop' 10 10 0.00017182
'func_sscanf_sprintf' 10 10 8.4928e-05
'func_sscanf_strjoin' 10 10 0.00056388
'func_str2num_cellfun' 10 10 0.00039231
'func_str2num_loop' 10 10 0.00033852
'func_str2num_sprintf' 10 10 0.00010862
'func_str2num_strjoin' 10 10 0.00057953
'func_textscan_cellfun' 10 10 0.00044585
'func_textscan_loop' 10 10 0.00024666
'func_textscan_sprintf' 10 10 9.4507e-05
'func_textscan_strjoin' 10 10 0.00056123
'solution_bsxfun_bytestream_Divakar' 10 10 0.00018166
'solution_bsxfun_bytestream_gpu_Divakar' 10 10 0.0029487
'solution_bsxfun_cumsum_Divakar' 10 10 0.00016396
'solution_bsxfun_sprintf_Divakar' 10 10 0.00012932
'solution_bsxfun_sprintf_gpu_Divakar' 10 10 0.002315
'solution_eval_loops_CSTLink' 10 10 0.00017191
'solution_loops_CSTLink' 10 10 6.5514e-05
'solution_mex_Amro' 10 10 6.4487e-05
'solution_mex_chappjc' 10 10 4.2507e-05
'solution_mex_omp_Amro' 10 10 0.00027411
'solution_mex_omp_chappjc' 10 10 0.00013017
'solution_sscanf_Divakar' 10 10 0.00020458
'solution_sscanf_char_LuisMendo' 10 10 0.00011144
'solution_textscan_sprintf_chappjc' 10 10 0.00010528
'func_eval_cellfun' 100 10 0.0011801
'func_eval_loop' 100 10 0.001059
'func_eval_sprintf' 100 10 0.00025547
'func_eval_strjoin' 100 10 0.0011824
'func_sscanf_cellfun' 100 10 0.0023356
'func_sscanf_loop' 100 10 0.0012338
'func_sscanf_sprintf' 100 10 0.00031012
'func_sscanf_strjoin' 100 10 0.0011334
'func_str2num_cellfun' 100 10 0.002635
'func_str2num_loop' 100 10 0.0028056
'func_str2num_sprintf' 100 10 0.00027899
'func_str2num_strjoin' 100 10 0.0012117
'func_textscan_cellfun' 100 10 0.0029546
'func_textscan_loop' 100 10 0.0018652
'func_textscan_sprintf' 100 10 0.00028506
'func_textscan_strjoin' 100 10 0.001125
'solution_bsxfun_bytestream_Divakar' 100 10 0.00040027
'solution_bsxfun_bytestream_gpu_Divakar' 100 10 0.0032536
'solution_bsxfun_cumsum_Divakar' 100 10 0.00041019
'solution_bsxfun_sprintf_Divakar' 100 10 0.00031089
'solution_bsxfun_sprintf_gpu_Divakar' 100 10 0.0026271
'solution_eval_loops_CSTLink' 100 10 0.0012294
'solution_loops_CSTLink' 100 10 0.00033501
'solution_mex_Amro' 100 10 0.00027069
'solution_mex_chappjc' 100 10 0.00010682
'solution_mex_omp_Amro' 100 10 0.00039385
'solution_mex_omp_chappjc' 100 10 0.00015232
'solution_sscanf_Divakar' 100 10 0.0010108
'solution_sscanf_char_LuisMendo' 100 10 0.00050153
'solution_textscan_sprintf_chappjc' 100 10 0.00026958
'func_eval_cellfun' 1000 10 0.0092491
'func_eval_loop' 1000 10 0.016145
'func_eval_sprintf' 1000 10 0.067573
'func_eval_strjoin' 1000 10 0.070024
'func_sscanf_cellfun' 1000 10 0.020954
'func_sscanf_loop' 1000 10 0.011224
'func_sscanf_sprintf' 1000 10 0.0022546
'func_sscanf_strjoin' 1000 10 0.0058568
'func_str2num_cellfun' 1000 10 0.024699
'func_str2num_loop' 1000 10 0.02645
'func_str2num_sprintf' 1000 10 0.05713
'func_str2num_strjoin' 1000 10 0.060093
'func_textscan_cellfun' 1000 10 0.02592
'func_textscan_loop' 1000 10 0.017589
'func_textscan_sprintf' 1000 10 0.0020249
'func_textscan_strjoin' 1000 10 0.0055364
'solution_bsxfun_bytestream_Divakar' 1000 10 0.0018817
'solution_bsxfun_bytestream_gpu_Divakar' 1000 10 0.0066003
'solution_bsxfun_cumsum_Divakar' 1000 10 0.001982
'solution_bsxfun_sprintf_Divakar' 1000 10 0.0015578
'solution_bsxfun_sprintf_gpu_Divakar' 1000 10 0.0046952
'solution_eval_loops_CSTLink' 1000 10 0.011481
'solution_loops_CSTLink' 1000 10 0.0027254
'solution_mex_Amro' 1000 10 0.0022698
'solution_mex_chappjc' 1000 10 0.0006967
'solution_mex_omp_Amro' 1000 10 0.0015025
'solution_mex_omp_chappjc' 1000 10 0.00041463
'solution_sscanf_Divakar' 1000 10 0.0093785
'solution_sscanf_char_LuisMendo' 1000 10 0.0038031
'solution_textscan_sprintf_chappjc' 1000 10 0.0020323
'func_eval_cellfun' 10000 10 0.083676
'func_eval_loop' 10000 10 0.098798
'func_eval_sprintf' 10000 10 0.60429
'func_eval_strjoin' 10000 10 0.63656
'func_sscanf_cellfun' 10000 10 0.20675
'func_sscanf_loop' 10000 10 0.1088
'func_sscanf_sprintf' 10000 10 0.021725
'func_sscanf_strjoin' 10000 10 0.052341
'func_str2num_cellfun' 10000 10 0.24192
'func_str2num_loop' 10000 10 0.26538
'func_str2num_sprintf' 10000 10 0.53451
'func_str2num_strjoin' 10000 10 0.56759
'func_textscan_cellfun' 10000 10 0.25474
'func_textscan_loop' 10000 10 0.17402
'func_textscan_sprintf' 10000 10 0.018799
'func_textscan_strjoin' 10000 10 0.04965
'solution_bsxfun_bytestream_Divakar' 10000 10 0.019165
'solution_bsxfun_bytestream_gpu_Divakar' 10000 10 0.031283
'solution_bsxfun_cumsum_Divakar' 10000 10 0.027986
'solution_bsxfun_sprintf_Divakar' 10000 10 0.017761
'solution_bsxfun_sprintf_gpu_Divakar' 10000 10 0.024821
'solution_eval_loops_CSTLink' 10000 10 0.10885
'solution_loops_CSTLink' 10000 10 0.025136
'solution_mex_Amro' 10000 10 0.021374
'solution_mex_chappjc' 10000 10 0.0060774
'solution_mex_omp_Amro' 10000 10 0.0076461
'solution_mex_omp_chappjc' 10000 10 0.002058
'solution_sscanf_Divakar' 10000 10 0.10503
'solution_sscanf_char_LuisMendo' 10000 10 0.035483
'solution_textscan_sprintf_chappjc' 10000 10 0.018772
'func_eval_cellfun' 1e+05 10 0.85115
'func_eval_loop' 1e+05 10 0.97977
'func_eval_sprintf' 1e+05 10 6.2422
'func_eval_strjoin' 1e+05 10 6.5012
'func_sscanf_cellfun' 1e+05 10 2.0761
'func_sscanf_loop' 1e+05 10 1.0865
'func_sscanf_sprintf' 1e+05 10 0.22618
'func_sscanf_strjoin' 1e+05 10 0.53146
'func_str2num_cellfun' 1e+05 10 2.4041
'func_str2num_loop' 1e+05 10 2.6431
'func_str2num_sprintf' 1e+05 10 5.4
'func_str2num_strjoin' 1e+05 10 5.6967
'func_textscan_cellfun' 1e+05 10 2.5696
'func_textscan_loop' 1e+05 10 1.7175
'func_textscan_sprintf' 1e+05 10 0.19759
'func_textscan_strjoin' 1e+05 10 0.50314
'solution_bsxfun_bytestream_Divakar' 1e+05 10 0.21884
'solution_bsxfun_bytestream_gpu_Divakar' 1e+05 10 0.23607
'solution_bsxfun_cumsum_Divakar' 1e+05 10 0.29511
'solution_bsxfun_sprintf_Divakar' 1e+05 10 0.19882
'solution_bsxfun_sprintf_gpu_Divakar' 1e+05 10 0.17923
'solution_eval_loops_CSTLink' 1e+05 10 1.0943
'solution_loops_CSTLink' 1e+05 10 0.2534
'solution_mex_Amro' 1e+05 10 0.21575
'solution_mex_chappjc' 1e+05 10 0.060666
'solution_mex_omp_Amro' 1e+05 10 0.072168
'solution_mex_omp_chappjc' 1e+05 10 0.024385
'solution_sscanf_Divakar' 1e+05 10 1.0992
'solution_sscanf_char_LuisMendo' 1e+05 10 0.36688
'solution_textscan_sprintf_chappjc' 1e+05 10 0.19755