Find mean of rows containing decimal numbers in between integers in a column
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I have a column with mostly decimal numbers and some integers
Example (the integers are in bold). - Y = [1 0.098 0.00076 0.01 2 0.099 0.007 2 0.003 0.04 0.1 4]. The integers range from 1 - 4.
I want to find the average of the numbers in between the integers, essentially [1 mean(0.098 0.00076 0.01) 2 mean (0.099 0.007) 2 mean(0.003 0.04 0.1) 4].
What would be the best way to do this? Is it recommended I turn the integers into a grouping variable?
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madhan ravi
2019년 8월 17일
편집: madhan ravi
2019년 8월 17일
Y = [1 0.098 0.00076 0.01 2 0.099 0.007 2 0.003 0.04 0.1 4];
Y=Y(:);
ix=diff(find(~mod(Y,1)))-1;
assert(nnz(~mod(Y,1))>2,'atleast one gap between integers is required')
y=Y(mod(Y,1)~=0);
V=mat2cell(y(1:sum(ix)),ix);
Wanted=cellfun(@mean,V)
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madhan ravi
2019년 8월 17일
편집: madhan ravi
2019년 8월 17일
Try the below, there was a minor error before:
Y=Y(:);
ii=~mod(Y,1);
ix=diff(find(ii))-1;
y=Y(mod(Y,1)~=0);
assert(~isempty(nonzeros(ix)),'Atleast one gap between integers is required')
V=mat2cell(y(1:sum(ix)),ix);
W=cellfun(@mean,V);
Wanted = zeros(nnz(ii)+numel(W),1);
Wanted(1:2:end) = Y(ii);
Wanted(2:2:end) = W
추가 답변 (3개)
Stephen23
2019년 8월 17일
편집: Stephen23
2019년 8월 18일
>> Y = [1,0.098,0.00076,0.01,2,0.099,0.007,2,0.003,0.04,0.1,4];
>> X = cumsum([1;diff(~mod(Y(:),1))]~=0);
>> Z = accumarray(X(:),Y(:),[],@mean)
Z =
1
0.03625333333333333
2
0.05300000000000001
2
0.04766666666666667
4
EDIT: minor changes based on comments below.
댓글 수: 6
Andrei Bobrov
2019년 8월 17일
+1
Y = [1,0.098,0.00076,0.01,2,0.099,0.007,2,0.003,0.04,0.1,4];
out = accumarray(cumsum([1;diff(mod(Y(:),1) == 0)~=0]),Y(:),[],@mean)
Bruno Luong
2019년 8월 17일
편집: Bruno Luong
2019년 8월 17일
Compact little gem, though I'm not fan of "~~x", IMO "x~=0" is clearer and perhaps faster.
darova
2019년 8월 17일
Use ismembertol() or ismember() (round values to some tolerance if needed) to find indices of integer values
Use loop to find mean
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KALYAN ACHARJYA
2019년 8월 17일
편집: KALYAN ACHARJYA
2019년 8월 17일
Its just the Jugaar non-efficient code
# Recomended not to use, I tried few minutes, hence I posted here
Y=[1 0.098 0.00076 0.01 2 0.099 0.007 2 0.003 0.04 0.1];
data1=find(Y>=1);
mean_data=zeros(1,length(data1));
for i=1:length(data1)
if i==length(data1)
mean_data(i)=mean(Y(data1(i)+1:end));
else
mean_data(i)=mean(Y(data1(i)+1:data1(i+1)-1));
end
end
mean_data
Result:
mean_data =
0.0363 0.0530 0.0477
*Elapsed time is 0.013581 seconds.
댓글 수: 2
madhan ravi
2019년 8월 17일
편집: madhan ravi
2019년 8월 17일
Kalyan the result is completely wrong. How did you assume it was 3??
mean_data=zeros(1,3);
How would you preallocate mean_data for the below example???
Y=[1 0.098 0.00076 0.01 2 0.099 0.007 2 0.003 0.04 0.1 4 .3 .1 .4 3 0 3];
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