block12.csharp.cs

// test one epoch on batches
testingError[epoch] = 0.0;
batchCount = 0;
testing_data.Batch(batchSize, (data, begin, end) =>
{
    // get the current batch for testing
    var featureBatch = features.GetBatch(testing_data, begin, end);
    var labelBatch = labels.GetBatch(testing_labels, begin, end);

    // test the network on the batch
    testingError[epoch] += evaluator.TestBatch(
        new[] {
            (features, featureBatch),
            (labels,  labelBatch)
        }
    );
    batchCount++;
});
testingError[epoch] /= batchCount;
Console.WriteLine($"{testingError[epoch]:F3}");