Math Interpreter

Python already supports math, whereby you can write code to add, subtract, multiply, or divide values and even variables. But let’s write a program that enables users to do math, even without knowing Python.

In a file called interpreter.py, implement a program that prompts the user for an arithmetic expression and then calculates and outputs the result as a floating-point value formatted to one decimal place. Assume that the user’s input will be formatted as x y z, with one space between x and y and one space between y and z, wherein:

x is an integer
y is +, -, *, or /
z is an integer

For instance, if the user inputs 1 + 1, your program should output 2.0. Assume that, if y is /, then z will not be 0.

Note that, just as python itself is an interpreter for Python, so will your interpreter.py be an interpreter for math!

Hints

Recall that a str comes with quite a few methods, per https://docs.python.org/3/library/stdtypes.html#string-methods, including split, which separates a str into a sequence of values, all of which can be assigned to variables at once.

For instance, if expression is a str like 1 + 1, then

x, y, z = expression.split(" ")

will assign 1 to x, + to y, and 1 to z.

Before You Begin

From the root of your repository execute cd conditionals So your current working directory is ...

/conditionals $:

Next execute

code interpreter.py

to make a file called interpreter.py where you’ll write your program.

Success

Your program must have a function called calculate that takes 3 parameters: x, y, and z. These parameters will be strings representing numbers or mathematical operators. For example, if the user types 1 + 1, then x would be "1", y would be "+", and z would be "1". It should return the result of the calculation as a float.

How to Test

Here’s how to test your code manually. At the conditionals/ $ prompt in your terminal: :

Run your program with python interpreter.py. Type 1 + 1 and press Enter. Your program should output:
```
2.0
```
Run your program with python interpreter.py. Type 2 - 3 and press Enter. Your program should output:
```
-1.0
```
Run your program with python interpreter.py. Type 2 * 2 and press Enter. Your program should output:
```
4.0
```
Run your program with python interpreter.py. Type 50 / 5 and press Enter. Your program should output:
```
10.0
```

Pytest

You can execute the below to check your code using pytest from the root directory.

pytest .\tests\conditionals\test_interpreter.py

A green output from running the test means it was successful. A red output means there is a bug in your code that you need to fix.

How to Submit

From github desktop or the command line, commit your changes and push them to your repository.

Codespaces

If you are using codespaces, you can commit your changes directly from the Codespace interface. Click on the Source Control icon in the left sidebar, then click on the "..." button and select "Commit to main". Enter a commit message and click "Commit".

Codespace terminal or your local terminal.

Note

You will need to have installed git-scm for this to work locally

At the /datatypes $ prompt in your terminal:

git add -A

Add all changed files in the repository to be committed

git commit -m "your message here"

Commit all changes in the REPO with the comment “your message here“ note: If the file is not complete, adjust the comment to describes what is being committed

Note

Remember to replace "your message here" with a meaningful commit message that describes your changes.

git push

Push all changes to the repo.