Feature Extraction
Overview
The first step to building a model
(see
machine learning process)
is to extract the necessary features of the data that the
model will train on. This process is typically known as
feature extraction.
Starting from an array of data, the feature extraction process will use
Array Transformations
to tranform the dataset to one that can be used by tensor-flow.
Transforming Data
Tensor flow takes records in the form of arrays. For example, a single record might look the following
let record = [1,0.05, 3.2];
This record has three features. Typically, dataset will be constructed to be objects with properties. An example
record might look like the following
let record = {diff:1, return:0.3, ratio:3.2}
let records = [{diff:1, return:0.03, ratio:3.2},
{diff:0.6, return:0.01, ratio:2.2},
{diff:1.1, return:0, ratio:1},
{diff:-0.2, return:-0.3, ratio:3}];
let transformed = records.map(p=>[p.diff, p.return, p.ratio])