Community Profile # Duncan Po

### MathWorks

Last seen: 24 Tage ago Active since 2013

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Split arrays in table into separate rows
I think you can do what you want in several steps. % Convert your cell arrays in voxel_coord, R2s, and MT into arrays using cel...

etwa ein Monat ago | 1

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Select a cell table
If you want the value in RESP0234_SOZ_TABLE{2,2}, use eval to evaluate that expression: for i=1:length(numbers); j=numbers...

etwa ein Monat ago | 0

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Timetable_Averaging values from each month
Use groupsummary with 'monthofyear' binning T = timetable(datetime(2000,1:(12*21),1)', rand(12*21,1), 'VariableNames', {'USDM_i...

etwa ein Monat ago | 0

Efficient way to standardize large amounts of text
You may be able to use patterns. For example, suppose the standard format is letters followed by underscore followed by numbers,...

etwa ein Monat ago | 0

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How to solve the Operator '-' is not supported for operands of type 'table'?
z should be a matrix instead of a table. z is defined using parentheses indexing in your code: z = LSinclination(:,5); This re...

6 Monate ago | 0

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splitting column in table without creating new variables
Unstack may be the function you need to convert your table into a column for each trial, and then use braces indexing to convert...

6 Monate ago | 0

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Merge columns with different cell input
Can you convert your empty char '' into empty array []? Tables can be concatenated with empty array but not empty char: t = tab...

6 Monate ago | 0

plot specific time points of everyday in an automated data
See this example of checking the hour component of a datetime, and then using logical indexing to extract a time range: dt = da...

6 Monate ago | 0

Plotting acceleration vs time on Matlab from accelerometer data that doesn't have a time column
You can create a timetable, and just supply the start time and frequency. Timetable will compute the timestamps for your data. F...

6 Monate ago | 0

Accessing data in matrix entries of tables
You can use multiple sets of curly braces {} to index into cells, and then use parentheses to index into the resulting arrays, l...

6 Monate ago | 1

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Categorize data in if else statement
You can discretize the BMI values into categories and then count them, like this: >> c = discretize(BMI, [0 18.5 24.9 29.9 34.9...

6 Monate ago | 1

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Find maximum for each Image in table
You can use groupsummary to find the maximum value of each group: T1 = groupsummary(T, 'MaxPosition', 'max', 'Intensity');

6 Monate ago | 2

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creating table of finely spaced xy points that represent a box corner
meshgrid may be the function you are looking for. For example, >> [x,y] = meshgrid(1:5,1:5) x = 1 2 3 4 ...

6 Monate ago | 0

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Rapid access and data manage of a table with cell array in the columns
You can use cellfun. For example, to compute the maximum of each column of the H3raw cell column for each row, do this: cellfun...

9 Monate ago | 0

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Plotting Timetable in Matlab
The line: Time=TR({'05-05-2020','05-06-2020 00:00:00'},:); only extracts two rows from TR. So Time only has two rows. Then w...

10 Monate ago | 0

Grouping based upon differences in time, with some small scatter
One way to do this is to use isbetween in a for loop, and then unique(, 'rows') to find the groups: t = datetime({'27-Aug-2020 ...

10 Monate ago | 0

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How can I track time periods under certain criteria?
You can put your data in a timetable and then use movsum like this: tt = readtimetable('Daily_Data_Thessaloniki.xlsx'); tt.thr...

10 Monate ago | 0

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PLOT ACTION IN TIME LAPS
Your data is best represented as a timetable in MATLAB. You can then use stackedplot to generate the visualization. haa = readt...

10 Monate ago | 1

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Spatial correlations with a timeseries
corr works on columns in 2D matrices. Your local temperature is a row, so you need to tranpose it: local_temp = local_temp...

10 Monate ago | 0

Combine timetables vertically different variables
You can use outerjoin with MergeKeys option set to true. You need to specify your common variable names (in addition to 'Time') ...

fast 2 Jahre ago | 1

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How to stackedplot with text data
What do you expect to see with your text data in the plot? stackedplot ignores text data, but plots categorical data. If your ...

etwa 2 Jahre ago | 0

What unit does the frequency have (MATLAB Color Histogram)?
The Y axis is number of pixels. The image in the example is 384x512, so it has 196608 pixels.

etwa 2 Jahre ago | 0

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Help with creating histogram
If you convert to categorical, you can sort the counts by descending order: a = randi(10,10,10); histogram(categorical(a), 'Di...

mehr als 2 Jahre ago | 0

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Is there a way to plot multiple graphs in one "subplot" of a stackedplot figure?
stackedplot can plot multiple lines in the same axes. One way is to have a non-column matrix as one of your table variables: x ...

mehr als 2 Jahre ago | 3

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I can't plot two lists as histograms as different colors on the same plot. Hist wants 'Numeric Input'
What does class(list1) return? If it returns anything other than a builtin numeric class, that would be the reason for your erro...

etwa 4 Jahre ago | 0

arrange multiple 2D histograms in 3D
You can use the hist function to plot one histogram, then grab its vertices from the resulting patch object. Pass these vertices...

mehr als 5 Jahre ago | 1

how to extract subbands from pyramidal directional filter bank/contourlet decomposition of an image?
You need the contourlet toolbox: <http://www.mathworks.com/matlabcentral/fileexchange/8837-contourlet-toolbox>

mehr als 5 Jahre ago | 0

Two bar graphs - two data sets - different bin width
histogram/histcounts have builtin support for Freedman-Diaconis rule: histogram(x, 'BinMethod', 'fd') or [n, binedges] ...

mehr als 5 Jahre ago | 0