Creating Visualizations

If you wish to create visualizations, you can either:

  1. save them as images to /valohai/outputs to be uploaded

  2. use our metadata system to render interactive graphs on the web interface

Visualizations from Metadata

Execution metadata is output by writing lines of JSON to the standard output stream.

For instance, in Python,

import json

print(json.dumps({"step": 190, "accuracy": 0.9247000813484192}))
print(json.dumps({"step": 200, "accuracy": 0.9262000918388367}))
print(json.dumps(({"model_layout": "ReLU8x-3xELUx32-softmax8"}))
{"step": 190, "accuracy": 0.9247000813484192}
{"step": 200, "accuracy": 0.9262000918388367}
{"model_layout": "ReLU8x-3xELUx32-softmax8"}

Each metadata point also has an implicit value _time which tells the metadata line was output. The _time value is in UTC, formatted as an ISO-8601 datetime (e.g. 2017-04-04T15:03:39.321000).

You can generate real-time charts based on metadata which helps with monitoring long runs so you can stop them if training doesn’t converge well.

Metadata chart comparison

You can sort executions by metadata values in the web interface which is useful for e.g. finding training executions with the highest prediction accuracy.

The latest or last value of each key such as accuracy can be used for the sorting hyperparameter optimization results.

Visualizing a confusion matrix

You can easily generate confusion matrices in Valohai.

The supported formats are:

  • An array of [['x', 'y', v], ['x', 'y', v], ...] triples (i.e. x label, y label, value)

  • A 2-dimensional array of the shape [[v, v, v], [v, v, v], ...]

  • A 2-dimensional array with a header for labels [['a', 'b', 'c'], [v, v, v], [v, v, v], ...]

For example:

from sklearn.metrics import confusion_matrix
import numpy as np

y_actu = [2, 0, 2, 2, 0, 1, 1, 2, 2, 0, 1, 2]
y_pred = [0, 0, 2, 1, 0, 2, 1, 0, 2, 0, 2, 2]

matrix = confusion_matrix(y_actu, y_pred)

# Convert to list
result = matrix.tolist()

print({"data": result})
# {'data': [[3, 0, 0], [0, 1, 2], [2, 1, 3]]}

Would result in:

Confusion matrix

What else can I do with metadata?

Beyond creating the visuals, based on metadata values you can for example:

  • Easily sort execution tables.

  • Easily compare executions.

  • Set early-stopping rules for executions and Tasks.

  • Set pipeline condititions.