Array values not corresponding to condition

1 次查看（过去 30 天）
Matlabhelp
Matlabhelp 2016-9-29
评论： Image Analyst 2020-8-25
Hello
I have an array that has been which has been rounded to numbers of 1-5. ( i'll post the code below ). I have numbers which aren't corresponding to my given condition and instead take another condition, i was wondering if anyone can spot what i've done wrong.
" Round data is a 20 by 20 array of numbers rounded to numbers 1,2,3,4,5)
rangeValue1 = 1;
rangeValue2 = 2;
rangeValue3 = 3;
rangeValue4 = 4;
rangeValue5 = 5;
roundData (roundData < 0.4 & roundData > 0 ) = rangeValue1;
roundData (roundData < 0.8 & roundData > 0.4 ) = rangeValue2;
roundData (roundData < 1.2 & roundData > 0.8 ) = rangeValue3;
roundData (roundData < 1.6 & roundData > 1.2 ) = rangeValue4;
roundData (roundData < 2.0 & roundData > 1.6 ) = rangeValue5;
  3 个评论
显示 1更早的评论
Matlabhelp
Matlabhelp 2016-9-29
编辑：Adam 2016-9-29
Alright
mydata = dlmread('data-1.csv',','); ( 20x20 matrix )
roundData = round(mydata,2); ( just so you know where round data came from )
input Columns 1 through 6
1.9000 1.0300 1.5100 0.6400 0.2100 2.0000
0.1400 0.2300 1.6900 1.4500 1.7700 5.0000
1.7600 0.6500 1.9300 1.0700 0.5700 3.0000
3.0000 3.0000 3.0000 5.0000 4.0000 2.0000
Output Columns 1 through 6
5.0000 3.0000 4.0000 2.0000 3.0000 2.0000
3.0000 3.0000 5.0000 4.0000 5.0000 5.0000
5.0000 2.0000 5.0000 3.0000 2.0000 3.0000
3.0000 3.0000 3.0000 5.0000 4.0000 2.0000
Image Analyst
Image Analyst 2020-8-25
Original question in case he deletes it like he's done with other posts:
Hello
I have an array that has been which has been rounded to numbers of 1-5. ( i'll post the code below ). I have numbers which aren't corresponding to my given condition and instead take another condition, i was wondering if anyone can spot what i've done wrong.
" Round data is a 20 by 20 array of numbers rounded to numbers 1,2,3,4,5)
rangeValue1 = 1;
rangeValue2 = 2;
rangeValue3 = 3;
rangeValue4 = 4;
rangeValue5 = 5;
roundData (roundData < 0.4 & roundData > 0 ) = rangeValue1;
roundData (roundData < 0.8 & roundData > 0.4 ) = rangeValue2;
roundData (roundData < 1.2 & roundData > 0.8 ) = rangeValue3;
roundData (roundData < 1.6 & roundData > 1.2 ) = rangeValue4;
roundData (roundData < 2.0 & roundData > 1.6 ) = rangeValue5;

请先登录，再进行评论。

请先登录，再回答此问题。

采纳的回答

Massimo Zanetti
Massimo Zanetti 2016-9-29
Your problems only arise because you used only "<" operators, so the numbers that are exactly in the middle of your intervals do not change. You should include "<=" operators, so that you will not loose any value re-mapping:
roundData (roundData <= 0.4 & roundData > 0 ) = rangeValue1;
roundData (roundData <= 0.8 & roundData > 0.4 ) = rangeValue2;
roundData (roundData <= 1.2 & roundData > 0.8 ) = rangeValue3;
roundData (roundData <= 1.6 & roundData > 1.2 ) = rangeValue4;
roundData (roundData <= 2.0 & roundData > 1.6 ) = rangeValue5;
Sure this work.

更多回答（1 个）

Adam
Adam 2016-9-29
编辑：Adam 2016-9-29
You are doing your changes in-place and in sequence, so those that were caught by the 1st condition get changed to 1 and then also get caught by the 3rd condition and changed to 3.
Take a copy of your matrix and run the condition off the original matrix instead.
Massimo Zanetti's answer is also something I intended to point out but forget and does result in potential gaps in your output, though not in the case of the example you showed. This is a secondary point that will show up less often, but still needs fixing.

类别

在 Help Center 和 File Exchange 中查找有关 Logical 的更多信息

标签

Community Treasure Hunt

Find the treasures in MATLAB Central and discover how the community can help you!

Start Hunting!

Translated by