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MATLAB - swarmchart3

Create a 3-D Swarm Chart

Read the BicycleCounts.csv data set into a timetable called tbl. This data set contains bicycle traffic data over a period of time. Display the first five rows of tbl. 

  tbl = readtable(fullfile(matlabroot,'examples','matlab','data','BicycleCounts.csv'));
tbl(1:5,:)

  
ans=5×5 table
         Timestamp              Day         Total    Westbound    Eastbound
    ___________________    _____________    _____    _________    _________

    2015-06-24 00:00:00    {'Wednesday'}     13          9            4    
    2015-06-24 01:00:00    {'Wednesday'}      3          3            0    
    2015-06-24 02:00:00    {'Wednesday'}      1          1            0    
    2015-06-24 03:00:00    {'Wednesday'}      1          1            0    
    2015-06-24 04:00:00    {'Wednesday'}      1          1            0

Create a vector x with the day name from each observation.

  daynames = ["Sunday" "Monday" "Tuesday" "Wednesday" "Thursday" "Friday" "Saturday"];
x = categorical(tbl.Day,daynames);

Create a categorical vector y containing the values "pm" or "am" according to the time for each observation in the table. Create vector z of eastbound traffic data. Then create a swarm chart of x, y, and z. The chart shows the data distributions for each morning and evening of the week.

  ispm = tbl.Timestamp.Hour < 12;
y = categorical;
y(ispm) = "pm";
y(~ispm) = "am";
z= tbl.Eastbound;
swarmchart3(x,y,z);
fig2plotly()

Specify Marker Size

Create vector x as a combination of zeros and ones, and create y as a vector containing all ones. Create z as a vector of squared random numbers. Then create a swarm chart of x, y, and z, and specify the size marker size as 5. 

  x = [zeros(1,500) ones(1,500)];
y = ones(1,1000);
z = randn(1,1000).^2;
swarmchart3(x,y,z,5);
fig2plotly()

Specify Marker Symbol

Create vector x as a combination of zeros and ones, and create y as a vector containing all ones. Create z as a vector of squared random numbers. Then create a swarm chart of x, y, and z, and specify the point ('.') marker symbol. 

  x = [zeros(1,500) ones(1,500)];
y = ones(1,1000);
z = randn(1,1000).^2;
swarmchart3(x,y,z,'.');
fig2plotly()

Vary Marker Color

Create vector x containing a combination of zeros and ones, and create y containing a random combination of ones and twos. Create z as a vector of squared random numbers. Specify the colors for the markers by creating vector c as the square root of z. Then create a swarm chart of x, y, and z. Set the marker size to 50 and specify the colors as c. The values in c index into the figure's colormap. Use the 'filled' option to fill the markers with color instead of displaying them as hollow circles.

  x = [zeros(1,500) ones(1,500)];
y = randi(2,1,1000);
z = randn(1,1000).^2;
c = sqrt(z);
swarmchart3(x,y,z,50,c,'filled');
fig2plotly()

Change Jitter Type and Width

Create vector x containing a combination of zeros and ones, and create y containing a random combination of the numbers one through four. Create z as a vector of squared random numbers. Then create a swarm chart of x, y, and z by calling the swarmchart function with a return argument that stores the Scatter object. Add x- and y-axis labels so you can see the effect of changing the jitter properties in each dimension.

  x = [zeros(1,500) ones(1,500)];
y = randi(4,1,1000);
z = randn(1,1000).^2;
s = swarmchart3(x,y,z);
xlabel('X')
ylabel('Y')
fig2plotly()

Change the shapes of the clusters of points by setting the jitter properties on the Scatter object. In the x dimension, specify uniform random jitter, and change the jitter width to 0.5 data units. In the y dimension, specify normal random jitter, and change the jitter width to 0.1 data units. The spacing between points does not exceed the jitter width you specify.

  s.XJitter = 'rand';
s.XJitterWidth = 0.5;
s.YJitter = 'randn';
s.YJitterWidth = 0.1;
fig2plotly()

Specify Target Axes

Read the BicycleCounts.csv data set into a timetable called tbl. This data set contains bicycle traffic data over a period of time. Display the first five rows of tbl. 

  tbl = readtable(fullfile(matlabroot,'examples','matlab','data','BicycleCounts.csv'));
tbl(1:5,:)

  
ans=5×5 table
         Timestamp              Day         Total    Westbound    Eastbound
    ___________________    _____________    _____    _________    _________

    2015-06-24 00:00:00    {'Wednesday'}     13          9            4    
    2015-06-24 01:00:00    {'Wednesday'}      3          3            0    
    2015-06-24 02:00:00    {'Wednesday'}      1          1            0    
    2015-06-24 03:00:00    {'Wednesday'}      1          1            0    
    2015-06-24 04:00:00    {'Wednesday'}      1          1            0

Create vector x with the days names for each observation. Create a categorical vector y containing the values "pm" or "am" according to the time for each observation in the table. Define ze as a vector of eastbound traffic data, and define zw as a vector of westbound traffic data. 

  daynames = ["Sunday" "Monday" "Tuesday" "Wednesday" "Thursday" "Friday" "Saturday"];
x = categorical(tbl.Day,daynames);
ispm = tbl.Timestamp.Hour<12;
y = categorical;
y(ispm) = 'pm';
y(~ispm) = 'am';
ze = tbl.Eastbound;
zw = tbl.Westbound;
fig2plotly()

Create a tiled chart layout in the 'flow' tile arrangement, so that the axes fill the available space in the layout. Call the nexttile function to create an axes object and return it as ax1. Then create a swarm chart of the eastbound data by passing ax1 to the swarmchart function.

  tiledlayout('flow')
ax1=nexttile;
swarmchart3(ax1,x,y,ze,'.');
fig2plotly()

Repeat the process to create a second axes object and a swarm chart for the westbound traffic.

  ax2 = nexttile;
z = tbl.Westbound;
swarmchart3(ax2,x,y,zw,'.');
fig2plotly()