Box Plot for Time (HH:MM:SS) data

Hi all, I am trying to get the boxplot for Time (HH:MM:SS) and day name data but unable to get the required plot. In detail, I would like to get the Boxplot in terms of days, (Monday to Sunday). I have attached the sample data and any help in this regard is highly appreciated.

[Cris LaPierre]

How should the median, interquartile range, and outliers be determined from your data?

Could you show us what the expected chart should look like?

[Ganesh Naik]

Hi Cris thanks for your response. I have managed to get box plot using command "boxplot(x,y)" for similar set of data where column A data (please refer to the figure) were the same (x -data) but column B data were numbers. For that I have got the plot (attached here). But now, I am not able to get the boxplot for the time (HH:MM:SS) data. I can easily do the box plot if column B contains numbers or decimals. It is also demonstrated for Matlab 'carsmall" data set as an example. So any help in getting the boxplot for time data (HH:MM:SS) would be highly appreciated.

[Cris LaPierre]

Yes, with numeric data, you can calculate medians and standard deviations. It looks like your data is a character array, meaning it is text. See Jonas' suggestion below.

Answer 1

[Jonas]

i suggest to convert you time (Hour : Minute : Seconds) to seconds using

[~, ~, ~, H, MN, S]=datevec('14:35:22','HH:MM:SS');
MN=MN+60*H;
S=S+MN*60;

then doing you boxplot thing and then converting your boxplot y labels back to a timestring

[Ganesh Naik]

Hi Jonas, thanks for your answer, I have managed to get the Box plot using your method. Is there any quick way to label the "Y-axis" data (see the pic) in terms of HH:MM:SS?

[Jonas]

just get your yticks, calculate hours, minutes and seconds, put it in a string and then set your ylabels to the strings generated

maybe this can help in the process https://de.mathworks.com/matlabcentral/answers/375392-convert-seconds-to-time

[Jonas]

or the other way around: if you have specific times you want to see, calculates them as seconds, set the values as yticks and then set the ylabels to the times you wanted

[Ganesh Naik]

Hi Jonas, thanks for your help. I am going to accept the answer.