matplotlib在混淆矩阵中绘制固定颜色

Question

Rather than using a colormap, is there a way to manually plot fixed colors into a confusion matrix? I'm trying to color the tiles green, red, yellow, and black for the top-left, top-right, bottom-left, and bottom-right respectively. Here's the code I have thus far:

def plot_confusion_matrix( cm_raw, title="Confusion Matrix", cmap=colors.ListedColormap( [
                       "lightgreen", "mistyrose", "lightyellow", "lightgray"] ) ):
    cm = cm_raw.astype( "float" ) / cm_raw.sum()

    plt.imshow( cm, interpolation="nearest", cmap=cmap )
    class_names = ["Negative", "Positive"]
    plt.title( title )
    plt.xlabel( "Predicted Label" )
    plt.ylabel( "True Label" )
    tick_marks  = np.arange( len( class_names ) )

    s = [["True Negative", "False Positive"], ["False Negative", "True Positive"]]
    for row_index in range( 2 ):
        for col_index in range( 2 ):
            plt.text( col_index, row_index, str( s[row_index][col_index]) + ":\n" + str( format(
            cm[row_index][col_index] * 100, ".2f" ) ) + "%", ha="center", color="black" )
    x_listsum = cm.sum( axis=0 ) * 100
    x_sum     = ["{0:.2f}%".format( x_index ) for x_index in x_listsum]
    y_listsum = cm.sum( axis=1 ) * 100
    y_sum     = ["{0:.2f}%".format( y_index ) for y_index in y_listsum]
    plt.xticks( tick_marks, x_sum )
    plt.yticks( tick_marks, y_sum )

    plt.show()

And here is the current output:

Confusion matrix

Answer 1

If you provide a Minimal, Complete, and Verifiable example, there is a chance that someone will help you do that. Else what can be said is that you need to create the values for your colors. Eg the pixels that should get the first color of the 4-color colormap, would be set to 0, those for the second to 0.33, for the third 0.66 and 1 for the last.