Calculate 1xn corrcoef

corrcoef.py

def corrcoef(X, Y):
    """
    Return Pearson correlation coefficients between 1 and n variables.
    
    Parameters
    ----------
    X : (1 x dim) matrix, single voxel
    Y : (n x dim) matrix, other voxels
    """
    X_no_mean = X - X.mean(keepdims=True)
    Y_no_mean = Y - Y.mean(axis=1, keepdims=True)
    
    return X_no_mean.dot(Y_no_mean.T)/X.std(keepdims=True)/Y.std(axis=1, keepdims=True)/X.shape[1]