Plot of a three dimensional matrix

Suppose I have a three dimensional matrix where the first index is the city, the second index is time. and the third index is temparature. I want to create a plot where the x axis is time. and y axis is the temperature of each city. Please advise how to proceed.

Answer 1

[Image Analyst]

Open the Volume Viewer App

• MATLAB® Toolstrip: Open the Apps tab, under Image Processing and Computer Vision, click the Volume Viewer app icon. Or...*
• MATLAB command prompt: Enter volumeViewer.

[alpedhuez]

Thank you. What will be the corresponding code?

[Walter Roberson]

volumeViewer does not support passing in coordinate vectors for the coordinates. There would not be any way for passing in meaningful names for the cities.

volumeViewer does support passing in a 4 x 4 reference matrix. That could be used to pass scaling and translation information for the time and temperature matrices.

[alpedhuez]

I would like to understand the code to write in the script. Thank you very much.

[Walter Roberson]

   volumeViewer(Your3DMatrix)

[Image Analyst]

Wait a minute. This does not seem like a 3-D matrix. If index 1 is the city number, and index 2 is the time index, and index 3 is the temperature index, then what is the value? For example, let's say we're looking at city #2, time point #4, and temperature index of 3. OK, fine, but what is the value stored at data(2, 4, 3)? It's not the temperature because that is the third index. So what is it? Is it the wind speed? Is it the cloud cover fraction? What is it???

OR do you actually have a 2-D array where for each city number and for each time point you have a single temperature? If so, you can simply use imshow() to show that 2-D temperature matrix, applying a colormap if you want. Or you could use surf() if you'd like a 3-D-ish perspective rendering.

[alpedhuez]

I mean, the data is the temperature of a city (LA, NY) in Jan-Dec. The output has temperatures of LA and NY in Y-axis and Jan-Dec in X-axis.

[Image Analyst]

OK, you threw us by calling it a 3-D data situation. What you have is a 2-D situation, NOT 3-D, and you can use 2-D ways of displaying it, like imshow(), imagesc(), image(), or surf().

[alpedhuez]

To be clear, consider the table

NY Jan 30

NY Feb 40

NY Mar 50

LA Jan 40

LA Feb 50

LA Mar 60

Then I want to define a variable LAtemp ={30,40,50} and also I want to have a plot with NY, LA temperature on Y axis and Months on X axis.

[Image Analyst]

Does anyone else understand this, or is it just me? What is LAtemp used for? Does he want a 2-D bar chart? Why not simply extract values for each city and plot them as a function of month?

[alpedhuez]

Yes. My question is "is there a simpler way than 'extract values for each city and plot them as a function of month'"?

[Walter Roberson]

The simpler ways of extract the values requires that the same number of months be present for each city and that all of the data for one city be together and sorted by month. In that case, take the temperature column as numeric and reshape() it by the number of entries per city so that all of the entries for one city go into a column. Then you can plot() the 2D array.