Removing rows except containing certain numbers of "33"

Hello everybody,

I hope to keep the row with the containing certain numbers of "33" of the last two digits in 1st column of result.

and I hope to remove other rows.

the expecting answer is [133 1133; 2, 4] in this case. ()

I tried with

result(~ismember(result(:,1),'33'), :) = []; % It does not work.

result(~contains(string(result(:,1)),"33"), :) = []; % 332 also is included in result variable.

but it doest not work. 332 also is included in result variable.

Is there a way to check wheter last two digits meet the condition?

x = [103 133 1133 1344 332 105 1105 15 53 511]';

y = [1 2 4 5 7 2 1 8 10 1]';

result = [x,y];

% How to remove the rows except containing certain numbers of 1st column of result

% if I would like to keep the row with the "33" of the last two digits in 1st column of result,

% 133 and 1133 accept the condition. and 332 does not meet the condition.

% so the expecting result will be [133 2; 1133, 4]

result(~ismember(result(:,1),'33'), :) = []; % It does not work.

result(~contains(string(result(:,1)),"33"), :) = []; % 332 also is included in result variable.

[Stephen23]

As Dyuman Joshi correctly wrote, mixing up text and numeric data will not help you.

Just stick to the numeric domain and use MOD or REM.

Answer 1

[Hiro Yoshino]

You should use "pattern" to detect what you want in the strings as follows:

Your data:

x = [103 133 1133 1344 332 105 1105 15 53 511]'; 
y = [1 2 4 5 7 2 1 8 10 1]';
result = [x,y]

result = 10×2

103 1 133 2 1133 4 1344 5 332 7 105 2 1105 1 15 8 53 10 511 1

Define pattern

pat = "33";
TF = endsWith(string(result(:,1)),pat);

Extract what I want

result(TF,:)

ans = 2×2

133 2 1133 4

Does this fit what you want to achieve?

[Smithy]

Thank you very much for your huge helps. I really really appreciate with it. It works really well for me.

Answer 2

[Dyuman Joshi]

You are trying to compare numeric data with character data. You will have to convert your initial data to do that comparison.

Instead, just use rem() or mod()

x = [103 133 1133 1344 332 105 1105 15 53 511]';
y = [1 2 4 5 7 2 1 8 10 1]';

%Checking condition - last two digits correspond to 33
idx = rem(x,100)==33;
%Values corresponding to the condition
result = [x(idx)';y(idx)']

result = 2×2

133 1133 2 4

[Stephen23]

+1 simpler and more efficient without the superfluous type conversions.