Name: 你好世界--機器學習食譜#1 (Hello World - Machine Learning Recipes #1)
Uploaded: 2021-01-14T06:05:16.000Z
Duration: 6 min 53 s
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to 不定詞

to write your first Machine Learning program.

walk you through writing Hello World for Machine learning.

we'll teach you how to get started with Machine

To do that, we'll work with two open source libraries,

But first, let's talk quickly about what Machine Learning is

You can think of Machine Learning as a subfield

Early AI programs typically excelled at just one thing.

at a championship level, but that's all it could do.

can solve many problems without needing to be rewritten.

As we speak, it's competing in the World Go Championship.

But similar software can also learn to play Atari games.

Machine Learning is what makes that possible.

I'll give you a problem that sounds easy but is

impossible to solve without Machine Learning.

Can you write code to tell the difference

Imagine I asked you to write a program that takes an image

You'd have to start by writing lots of manual rules.

to count how many orange pixels there are and compare that

The ratio should give you a hint about the type of fruit.

That works fine for simple images like these.

you'll find the real world is messy, and the rules you

How would you write code to handle black-and-white photos

or images with no apples or oranges in them at all?

In fact, for just about any rule you write,

and that's just to tell the difference between apples

If I gave you a new problem, you need to start all over again.

And for that, we're going to train a classifier.

For now you can think of a classifier as a function.

It takes some data as input and assigns a label to it

and want to classify it as an apple or an orange.

Or I have an email, and I want to classify it

automatically is called supervised learning.

It begins with examples of the problem you want to solve.

To code this up, we'll work with scikit-learn.

Here, I'll download and install the library.

There are a couple different ways to do that.

But for me, the easiest has been to use Anaconda.

This makes it easy to get all the dependencies set up

With the magic of video, I'll fast forward

by starting a Python script and importing SK learn.

Assuming that worked, that's line one of our program down,

follow a recipe with a few standard steps.

These are examples of the problem we want to solve.

For our problem, we're going to write a function

For starters, it will take a description of the fruit

an apple or an orange as output, based on features

We'll look at different apples and oranges

and write down measurements that describe them in a table.

To keep things simple, here we've used just two--