Create Structure Fields with and Array of Strings

Hello!

Please keep in mind that I'm new to MATLAB.

Structures seem great...but the idea of having to iteratively enter field names for data entry seems ridiculous. Are there any good postings or is there any good advice for creating a strcture in a more automated manner?

Here's what I'm trying to do...

Say I have a "large" data set 3x30 with 30 different fieldNames for the data.

fieldNames={'volts' 'horsepower' 'force' ... 'STDev'} %These are the column headers

Now let's say I have 3 different testConfigurations.

testConfigurations={'noCarLoad';'heavyCarLoad';'lowFuel'} %These are the row headers

Finally, I've done this experiment for 4 different vehicleNames.

vehicleNames = {'Ford' 'Lincoln' 'Chevy' 'Porsche'}

Thus, I have four 3x30 matrices of data.

I want to enter all of this data into a structure called testData and I would like to do it in a way where I don't have to manually enter in all these different fields. All my data is currently in an Excel format with data for each vehicle residing on its own worksheet.

Any suggestions to streamline the structure building process? I really don't feel like having to manually enter 30 field names if I don't have to!!!

Thank you!

Answer 1

[Fangjun Jiang]

help cell2struct

And a place to learn struct. http://blogs.mathworks.com/loren/category/structures/

However, your data is better represented using 3 dimension data.

Names={'volts' 'horsepower' 'force' 'STDev'};
N=length(Names);
Names=cell2struct(mat2cell(1:N,1,ones(N,1)),Names,2)

Vehicle = {'Ford' 'Lincoln' 'Chevy' 'Porsche'};
N=length(Vehicle);
Vehicle=cell2struct(mat2cell(1:N,1,ones(N,1)),Vehicle,2)

Config={'noCarLoad';'heavyCarLoad';'lowFuel'};
N=length(Config);
Config=cell2struct(mat2cell(1:N,1,ones(N,1)),Config,2)

Names = 
         volts: 1
    horsepower: 2
         force: 3
         STDev: 4
Vehicle = 
       Ford: 1
    Lincoln: 2
      Chevy: 3
    Porsche: 4
Config = 
       noCarLoad: 1
    heavyCarLoad: 2
         lowFuel: 3

If Data=rand(10,10,10), you can reference your data as

Data(Names.volts,Vehicle.Ford,Config.noCarLoad)

[John F]

I think we're on to something here! Thanks a lot!

[Fangjun Jiang]

Set up your three dimension data correctly, you'll be able to use

Data(:,Vehicle.Ford,:) for all the testing data for Ford vehicles, similarly, Data(:,:,Config.noCarLoad) will be testing data for all the "NoCarLaod" configuration.

Answer 2

[Walter Roberson]

It can probably be done, but please clarify what you would like the result to look like. For example are you looking for

testdata.Porsche.heavyCarLoad.horsepower

to be a scalar?

Or perhaps

testdata(4).horsepower

should be a vector of 3 values related to Porsche, one value for each test configuration?

[John F]

I'd prefer testdata.Porsche.heavyCarLoad.horsepower

[John F]

here's an example of what I DON'T want...

here are my inputs, except now we're talking about ships:

shipNames =

'xCraft'

'JHHS_Axial_2734'

'JHHS_Axial_2460'

'LCS_1'

'LCS_2_inboard'

'LCS_2_outboard'

'LCS_3_3251'

'LCS_5_X'

dimType =

'D3' 'CL' 'Length_inboard' 'Length_outboard' 'Lambda'

shipData=struct('ShipName',{shipNames},'DimType',{dimType})

shipData =

ShipName: {8x1 cell}

DimType: {'D3' 'CL' 'Length_inboard' 'Length_outboard' 'Lambda'}

What I want to be able eventually do is say...

shipData.xCraft.D3 = data for xCraft at D3

Any suggestions?