# What I want:

Take an input, x

Take a formula. It has to be capable of reading something in the format:

• ax^m + bx^n + cx^o ... where m, n, o and any terms after that can represent any value.
• coefficients, again for any number. For example, 6x^2. (That means 6(x^2))
• Doesn't necessarily have to put up with spaces
• times, divide, plus and minus
• brackets - up to stacking of 5
• ANY negative numbers
• fractions
• To the power of x , these can be integeric (<-- is not a word, but that is the best word I can make up!)
• If x = 5, you can put -x to get -5 and -x^2 is -(x^2). You could use (-x)^2

After it interprets the formula, it has to plug x into the function, then output the value.

## The Challenge:

• Do it in as less bytes as possible
• The lowest number of bytes wins!

# Example

Key: bp = Background Process

• Give me an input, (x)

4

• Give me a formula:

2^x

• (bp) So I have to do 2 to the power of x, which is 2^4, which is 16
• Output: 16
• >Something in the form of ax means a*x Apr 28 '17 at 15:38
• Does 6-x^2 mean 6 * -(x^2) or 6 * ((-x)^2)? Apr 28 '17 at 15:40
• I'm really not sure as to what this challenge is asking, could you at least add some test-cases? Apr 28 '17 at 15:41
• Very closely related, almost duplicate. I'm not sure that adapting the answers to include the use of x would make a significant change to the solutions.
– user62131
Apr 28 '17 at 15:58
• @ScottMilner: If I thought it was an exact duplicate I'd have thrown a close vote on. (And given that I got dupehammer rights yesterday, it'd close the challenge by itself.) I don't think it's quite close enough to do that, but it's certainly close enough to make people aware of the possibility.
– user62131
Apr 28 '17 at 16:12

# TI BASIC, 6 bytes

This might change, since the rules are still not totally stable, but I wanted to post this while I could.

:Prompt X,F
:F


Asks for X, then parses whatever formula is put into F and displays it.

If I could assume that X was already stored in the memory, it would be

# TI BASIC (maybe), 0 bytes

Is this ok?Guess not. :-(

• How do I test this? Apr 28 '17 at 15:53
• @simplest_mathematics If you have a TI-83/84 calculator, you can create a new program and plug it in. If not, you can find emulators online. Apr 28 '17 at 15:55
• I still don't understand Apr 28 '17 at 15:59
• A blank code block is <pre></pre>. However, I'm pretty sure the second answer won't work because it would need to take input with X= preceding it, which means you're taking input via a variable, something that's not allowed by default on PPCG.
– user62131
Apr 28 '17 at 16:03
• TI BASIC is the programming language of TI 83/84 graphing calculators. You can create full programs in this language. You can find more information here Apr 28 '17 at 16:03