[問題] randn函數已回收
想問同樣造出1000x100 randn的矩陣,
為何以下兩個程式所花時間會差那麼多?
(1)
tic
for i=1:1000
for j=1:100
z(i,j)=randn;
end
end
toc
約 0.13s
(2)
tic
z=randn(1000,100);
toc
約 0.0023s
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◆ From: 118.168.2.207
※ 編輯: sapajou 來自: 118.168.2.207 (01/29 21:43)
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01/29 21:54, , 1F
01/29 21:54, 1F
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01/29 23:57, , 2F
01/29 23:57, 2F
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01/30 00:12, , 3F
01/30 00:12, 3F
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01/30 00:33, , 4F
01/30 00:33, 4F
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01/30 01:49, , 5F
01/30 01:49, 5F
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01/30 11:12, , 6F
01/30 11:12, 6F
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01/30 12:00, , 7F
01/30 12:00, 7F
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02/01 18:17, , 8F
02/01 18:17, 8F
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02/01 19:32, , 9F
02/01 19:32, 9F
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02/01 19:38, , 10F
02/01 19:38, 10F
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02/02 01:46, , 11F
02/02 01:46, 11F