I'm getting an error when I was using compute_mapping function for pca, please give me any suggestions how can I solve it?

Error using internal.stats.parseArgs (line 42)

Wrong number of arguments.

Error in pca (line 174)

= internal.stats.parseArgs(paramNames, defaults, varargin{:});

Error in compute_mapping (line 309)

if isempty(varargin), [mappedA, mapping] = pca(A, no_dims);

Error in run_feature (line 34)

[P_A_feature, mapping1] = compute_mapping(P_A_feature, 'PCA', 28); //this is the code i wrote

Answer 1

[Aditya]

Hi Bhawna,

The error message you're encountering suggests that there's an issue with the number of arguments being passed to a function, likely the pca function. In your case, it seems to be related to how compute_mapping is calling pca.

To troubleshoot and resolve this issue, let's go through a few steps:

1. Verify compute_mapping Implementation: Ensure that the compute_mapping function is correctly implemented to handle PCA. It should call the pca function with the correct number of arguments. Here's a simplified example of how compute_mapping might handle PCA:

function [mappedA, mapping] = compute_mapping(A, method, no_dims)
    if strcmpi(method, 'PCA')
        [coeff, score, latent, tsquared, explained, mu] = pca(A, 'NumComponents', no_dims);
        mappedA = score;  % The transformed data
        mapping.coeff = coeff;
        mapping.latent = latent;
        mapping.explained = explained;
        mapping.mu = mu;
    else
        error('Unknown method.');
    end
end

2. Arguments for pca: The pca function in MATLAB can take additional parameters, such as 'NumComponents', to specify the number of principal components. Make sure these parameters are correctly passed.