replacing numbers with text
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Hello everyone,
I want to replace text with numbers. 1=s, 3=r, 4=b . I tried 2 methods. Cant figure why niether of the codes wont work . What am I doing wrong?
% Method 1 / not working returns "Index exceeds the number of array elements (3)." error
mymat= [ 4 4 4
3 4 4
1 4 4
4 3 4
3 3 3
1 3 4
4 1 4]
t = string(["b", "r", "s"])
comMat = t(mymat)
%Method 2 / returns a NaN matrix and that's not what I want.
mymat= [ 4 4 4
3 4 4
1 4 4
4 3 4
3 3 3
1 3 4
4 1 4]
mymat(mymat==4)= "b"
mymat(mymat==3)= "r"
mymat(mymat==1)= "s"
mymat
thank you for your time in advance.
采纳的回答
Here's a more flexible alternative.
mymat= [ 4 4 4
3 4 4
1 4 4
4 3 4
3 3 3
1 3 4
4 1 4];
t = ["s", "r", "b"];
v = unique(mymat(:)); % or maybe you want unique(mymat(:),'stable')
B = string(categorical(mymat,v,t))
Also works for any values
mymat(mymat==4) = 10;
mymat(mymat==1) = -42.5
B = string(categorical(mymat, unique(mymat(:)), ["s", "r", "b"]))
Another alternative
B= discretize(mymat, [unique(mymat(:));inf], ["s", "r", "b"])
更多回答（2 个）
Image Analyst
2020-12-29
Well here's one way. Using a simple for loop
mymat= [ 4 4 4
3 4 4
1 4 4
4 3 4
3 3 3
1 3 4
4 1 4]
t = string(["b", "", "r", "s"])
[rows, columns] = size(mymat)
for col = 1 : columns
for row = 1 : rows
output(row, col) = t(mymat(row, col));
end
end
output % Show in command window.
I'm sure other people will show you other ways.
The easiest is to replace the numbers by ASCII codes corresponding to your letters and then convert to char. You can index each character as a normal matrix i.e. comMAT(1,1)
I have edited the answer to make it generic
comMAT=nan(size(mymat));
comMAT(mymat==4)=98;
comMAT(mymat==3)=114;
comMAT(mymat==1)=115;
comMAT=char(comMAT);
2 个评论
Nice and simple, but has the disadvantage that it requires hard-coding each value separately, it could be looped to avoid that.
Important: this works because the output array is distinct from the input array. Note that the char conversion can be applied on the first line.
I was assuming the objective was replacing single digit int by alphanumerical. That piece of code does that in a simple way. It can be very easily generalized if the output matrix comMAT is initialized to NaN and the transformation is done there. For a lot of values it will require a for loop that in that case is not very elegant solution, I agree.
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