Array values not corresponding to condition

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;

[Massimo Zanetti]

Please, post your input matrix and output matrix. Because your code seems fine.

[Matlabhelp]

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]

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;

Answer 1

[Massimo Zanetti]

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.

[Matlabhelp]

Alright thanks heaps

Answer 2

[Adam]

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.