Array divided by 255 gives me 0
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I have an matrix that looks like this (but bigger)
[30 29 31;
29 30 30;
30 31 30]
now when I divide it by 255, it gives me this:
[0 0 0;
0 0 0;
0 0 0]
As far as I know I never changed anything with digits, does anyone have an idea what's going on?
Kind regards
edit: the matrix contains doubles
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답변 (2개)
Joep
2015년 4월 7일
편집: Joep
2015년 4월 7일
This is because you matrix was written in uint8. You should first convert it to double.
double([30 29 31; 29 30 30; 30 31 30])
It's not clear why it is in uint8 maybe you load some image or create uint8 matrix.
PS: uint8 means you got a 8 bit number so 2^8=256 which will give 0->255. If you need some help I can help you also in dutch.
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James Tursa
2015년 4월 7일
Most likely you thought you had converted it to double, but hadn't. Then you restarted MATLAB and wiped out the evidence.
Ilham Hardy
2015년 4월 7일
testmat = [30 29 31; 29 30 30; 30 31 30] ;
testmat =
30 29 31
29 30 30
30 31 30
>> testmatdev = testmat./255
testmatdev =
0.1176 0.1137 0.1216
0.1137 0.1176 0.1176
0.1176 0.1216 0.1176
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