Using is outlier with threshold

I need to only plot the outliers that are out of my upper and lower limits. But I get a percentile error using TF= (A,'percentiles',threshold)

Below is my code and plot with out apply threshold to outlier.

XT{1} is a cell array of data.

%% Plot the control charts:

%For all the states (states 1, 3, 10, 12, 14), plot x(t), shown in blue in the hint below.

timev=zeros(1020,1);% initalize time vector

for i= 1:1020;

timev(i)= timev(i)+int*(8*(i)+30);

end

threshold=[LCL,UCL];

[TF]= isoutlier(XT{1},) %'percentiles',threshold)

%Create a new figure

figure('Renderer', 'painters', 'Position', [10 10 1200 900])

plot( timev, XT{1}, timev(TF),XT{1}(TF),'x')

hold on

%Plot the control limits CL, UCL, and LCL as horizontal lines in green. Remember that

%these limits are the same for all plots (calculated from state 1).

yline(CL,'g')% plot the control limits

yline(UCL,'g')% plot the upper control limits

yline(LCL,'g')% plot the lower control limits

Answer 1

[Star Strider]

You have a typographical error. It should be 'percentiles', not 'percentile'.

From the documentation:

TF = isoutlier(A,'percentiles',threshold) defines outliers as points outside of the percentiles specified in threshold. The threshold argument is a two-element row vector containing the lower and upper percentile thresholds, such as [10 90].

.

[Mande Hudson]

Hi, yes I have tried percentiles but I get this error:

Error using isoutlier>parseinput (line 196)

Expected input number 2 to match one of these values:

'median', 'mean', 'quartiles', 'grubbs', 'gesd', 'movmedian', 'movmean', 'SamplePoints', 'DataVariables', 'ThresholdFactor', 'MaxNumOutliers'

The input, 'percentiles', did not match any of the valid values.

Error in isoutlier (line 90)

[method, wl, dim, p, sp, vars, maxoutliers] = parseinput(a, varargin);

Error in hudsonhwk9 (line 191)

TF= isoutlier(XT{1},'percentiles',threshold);

>>

[Star Strider]

The current documentation (and my reference) is for R2021a.

What version/release are you using?

The syntax works with R2021a —

X{1} = rand(1, 100);
t = 1:numel(X{1});
TF = isoutlier(X{1},'percentiles',[20 80])

TF = 1×100 logical array
   0   0   0   0   0   1   1   0   0   0   1   1   0   0   1   0   1   0   0   0   0   0   1   0   1   0   0   1   0   0   0   0   0   1   1   0   1   0   0   0   0   1   1   0   1   0   0   0   0   0

figure
plot(t,X{1})
hold on
plot(t(TF),X{1}(TF),'x')
yline(0.20)
yline(0.80)
hold off
grid

.

[Mande Hudson]

Im using R2018b

[Star Strider]

Please check the documentation for your version. The 'percentiles' option is not available in isoutlier in R2018b, however the prctile function is.

Instead, do something like this —

X{1} = rand(1, 100);
t = 1:numel(X{1});
p = prctile(X{:},[20 80])

p = 1×2

0.1945 0.7994

TF = (X{1}<=p(1)) | (X{1}>=p(2))                            % Logical Index Of Values Outside The Respective Percentiles

TF = 1×100 logical array
   1   1   1   0   0   0   0   1   0   1   0   1   0   1   1   0   1   0   0   1   0   0   0   0   1   0   0   0   0   0   1   1   1   0   1   1   0   0   1   1   0   0   0   0   0   0   1   0   1   0

figure
plot(t, X{1})
hold on
plot(t(TF), X{1}(TF),'x')
yline(0.2)
yline(0.8)
hold off
grid

That will identify them.

Then do whatever you want to with them after that.

.