Chapter 2 || Strings and factors || python convert string to categorical

Chapter 2

Strings and factors

If it's not too much trouble, remember the accompanying realities.

• v My name is Mark.

• v My ethnicity is the U.S.

 

Since you've remembered my name and identity, I will not need to repeat them. On the off chance that I say to you, "You most likely know others who have my name," you'll realize I'm alluding to "Mark."

In the event that I find out if my identity is equivalent to yours, I will not need to ask, "Is your ethnicity equivalent to the U.S.?" I'll ask, "Is your ethnicity equivalent to my ethnicity?" You'll recollect that when I say "my identity," I'm alluding to "U.S.", and you'll contrast your ethnicity and "U.S.", despite the fact that I haven't said "U.S." expressly.

In these models, the terms my name and my identity work a similar way Python factors do. my name alludes to a specific worth, "Mark". similarly, a variable alludes to a specific worth. You could say that my name is a variable that alludes to the string Mark. A variable is made thusly:

 

name = "Mark"

 

Presently the variable name alludes to the content string "Mark".

Note that it was my decision to call it to name. I might have called it my name, x y z lol, or something different. It's up to me how to name my factors, inside cutoff points. More on those cutoff points later.

 

With the string "Mark" doled out to the variable name, my Python code doesn't need to determine "Mark" once more. At whatever point Python experiences name, Python realizes that it's a variable that alludes to "Mark".

For instance, on the off chance that you compose...

name = "Mark"

print(name)

 

…Python shows…

Mark

The worth that a variable alludes to can change.

We should return to the first models, the realities I requested that you remember. These realities can change, and in the event that they do, the terms my name and my identity will allude to new qualities.

I could go to court and change my name to Ace. At that point, my name is presently don't Mark. On the off chance that I need you to address me effectively, I'll need to reveal to you that my name is presently Ace. After I reveal to you that, you'll realize that my name doesn't allude to the worth it used to allude to (Mark), yet alludes to another worth (Ace).

In the event that I procure U.K. citizenship, my ethnicity is no longer the U.S. It's the U.K. On the off chance that I need you to know my ethnicity, I'll need to disclose to you that it is presently the U.K. After I reveal to you that, you'll realize that my ethnicity doesn't allude to the first worth, "The U.S.", however now alludes to another worth, U.K.

Python factors can likewise change.

In the event that I code...

 

name = "Mark"

 

…name alludes to "Mark". At that point, I tag along later and code the line...

 

name = "Ace"

 

Before I coded the new line, in the event that I requested that Python print name, it showed...

 

Mark

Yet, that was at that point.

 

Presently if, having composed…

 

name = "Ace"

 

…in the event that I compose…

 

print(name)

… Python shows...

Ace

A variable can have quite a few qualities, yet just each in turn.

Python variable names have no intrinsic significance to Python.

In English, words have meaning. You can't utilize only any word to convey. I can say, "My name is Mark," in any case, on the off chance that I need to be perceived, I can't say, "My flogged is Mark." That's jabber.

However, with factors, Python is in regards to semantics. You can utilize only any word (as long as it doesn't defy the norms of variable-naming, which I'll cover later).

From Python's perspective...

 

flogged = "Mark"

...is similarly pretty much as great as...

name = "Mark"

On the off chance that you compose...

flogged = "Mark"

...at that point compose…

print(flogged)

…Python shows...

 

Mark

 

Inside cutoff points, you can name factors anything you need, and Python will not give it a second thought.

 

Lesson author = "Mark"

guy who keeps saying his own name = "Mark"

x = "Mark"

 

Python's visual impairment to importance regardless, with regards to variable names, you'll need to give your factors significant names, since it'll help you and different comprehend your code.

 

Again, the syntactic contrast between factors and text strings is that factors are never encased in statements, and text strings are constantly encased in statements.

It's consistently...

 

Last name = "Smith"

city of origin = "New Orleans"

aussie greeting = " g 'Day"

 

On the off chance that it's a letter set letter or word, and it isn't encased in statements, and is anything but a watchword that has extraordinary importance for Python, similar to print, it's a variable.

In the event that it's a few characters encased in statements, it's a content string.

On the off chance that you haven't seen, let me bring up the spaces between the variable and the equivalent sign, and between the equivalent sign and the worth.

 

moniker = "Pal"

 

These spaces are a style decision as opposed to a lawful necessity. Be that as it may, I'll request that you remember them for your code all through the training works out.

In the last section, you figured out how to compose...

Print ("Hello, World!")

 

At the point when the code executes, Python shows Hello World! on the screen.

Be that as it may, imagine a scenario you composed these two articulations all things being equal (the line numbers are added naturally by the altering program; they're not piece of the code):

 

1 thanx = "Much obliged for your info!"

2 print(thanx)

 

Rather than putting a book string inside the brackets of the print proclamation, the code above first appoints the content string to a variable, thanx. At that point, it puts the variable, not the string, inside the enclosures. Since Python consistently substitutes the incentive for the variable, Python shows—not the variable name thanx—but rather the content to which it alludes, "Much obliged for your info!" Thanks for your information! shows.

In the model above, notice that every assertion is on a different line.

I referenced that you need to adhere to specific standards for naming factors. One that I've just covered: You can never encase a variable name in quotes marks.

Here's a subsequent guideline: Variable names can't have spaces in them.

nation of root is anything but a legitimate variable name. It must be…

country of origin

…or, better for lucidness…

Country of origin

I'll cover a couple of more principles for naming factors instantly.