# Coding question **URL:** \ **Category:** Questions\ **Created:** [October 20, 2025, 7:48pm UTC](https://cl.desmos.com/t/coding-question/8317 "2025-10-20T19:48:09Z")\ **Posts on this page:** 20\ **Page:** 1
**Author:** ![Edward\_Ankrom](https://yyz1.discourse-cdn.com/flex031/user_avatar/cl.desmos.com/edward_ankrom/32/8589_2.png) [@Edward\_Ankrom](https://cl.desmos.com/u/Edward_Ankrom)\ **Post date:** [October 20, 2025, 7:48pm UTC](https://cl.desmos.com/t/coding-question/8317/1 "2025-10-20T19:48:09Z")
![image](https://canada1.discourse-cdn.com/flex031/uploads/desmos/original/2X/2/2bb2c36a7b4938db0b6120aee30325e5df0c1702.jpeg) ---
**Author:** ![Daniel\_Grubbs](https://yyz1.discourse-cdn.com/flex031/user_avatar/cl.desmos.com/daniel_grubbs/32/719_2.png) [@Daniel\_Grubbs](https://cl.desmos.com/u/Daniel_Grubbs)\ **Post date:** [October 20, 2025, 7:49pm UTC](https://cl.desmos.com/t/coding-question/8317/2 "2025-10-20T19:49:52Z")
What is your question with the coding? The equation shown is coded by what the arrow is pointing at, although I think the slash before the “x” is unnecessary. The general syntax for a fraction as latex is `\frac{numerator}{denominator}`. ---
**Author:** ![Edward\_Ankrom](https://yyz1.discourse-cdn.com/flex031/user_avatar/cl.desmos.com/edward_ankrom/32/8589_2.png) [@Edward\_Ankrom](https://cl.desmos.com/u/Edward_Ankrom)\ **Post date:** [October 20, 2025, 9:14pm UTC](https://cl.desmos.com/t/coding-question/8317/3 "2025-10-20T21:14:19Z")
![image](https://canada1.discourse-cdn.com/flex031/uploads/desmos/original/2X/7/7d5501d9b0d523c429dc0650d84f9ade23547bcd.png) I entered this equation and the check box will check green but stays an X. ---
**Author:** ![Daniel\_Grubbs](https://yyz1.discourse-cdn.com/flex031/user_avatar/cl.desmos.com/daniel_grubbs/32/719_2.png) [@Daniel\_Grubbs](https://cl.desmos.com/u/Daniel_Grubbs)\ **Post date:** [October 20, 2025, 9:16pm UTC](https://cl.desmos.com/t/coding-question/8317/4 "2025-10-20T21:16:02Z")
Can you share a link to your activity so I can look at the rest of your code? Specifically, I’d guess it has something to do with `valid`. ---
**Author:** ![NTMDev](https://yyz1.discourse-cdn.com/flex031/user_avatar/cl.desmos.com/ntmdev/32/7141_2.png) [@NTMDev](https://cl.desmos.com/u/NTMDev)\ **Post date:** [October 21, 2025, 1:40am UTC](https://cl.desmos.com/t/coding-question/8317/5 "2025-10-21T01:40:29Z")
Am I wrong or doesn’t `simpleFunction` need an `identifier` for the variables in it? `simpleFunction(“y=\frac{5}{2}x-2”,”y”,”x”)` ---
**Author:** ![Daniel\_Grubbs](https://yyz1.discourse-cdn.com/flex031/user_avatar/cl.desmos.com/daniel_grubbs/32/719_2.png) [@Daniel\_Grubbs](https://cl.desmos.com/u/Daniel_Grubbs)\ **Post date:** [October 21, 2025, 4:09am UTC](https://cl.desmos.com/t/coding-question/8317/6 "2025-10-21T04:09:09Z")
> [@NTMDev](#): > > doesn’t `simpleFunction` need an `identifier` for the variables in it? If there is no identifier, `simpleFunction()` defaults to in terms of x. An equation like `y=\frac{5}{2}x-2` is treated as `f(x)=\frac{5}{2}x-2`, so no variable arguments are necessary. Conversely, `2y=\frac{5}{2}x-2` is an implicit equation and can’t be treated as a function because there is no isolated variable. ---
**Author:** ![NTMDev](https://yyz1.discourse-cdn.com/flex031/user_avatar/cl.desmos.com/ntmdev/32/7141_2.png) [@NTMDev](https://cl.desmos.com/u/NTMDev)\ **Post date:** [October 21, 2025, 11:12am UTC](https://cl.desmos.com/t/coding-question/8317/7 "2025-10-21T11:12:35Z")
Oh. Then I don’t see any problem here! ---
**Author:** ![Edward\_Ankrom](https://yyz1.discourse-cdn.com/flex031/user_avatar/cl.desmos.com/edward_ankrom/32/8589_2.png) [@Edward\_Ankrom](https://cl.desmos.com/u/Edward_Ankrom)\ **Post date:** [October 21, 2025, 4:27pm UTC](https://cl.desmos.com/t/coding-question/8317/8 "2025-10-21T16:27:18Z")
> [@NTMDev](#): > > simpleFunction(“y=\frac{5}{2}x-2”,”y”,”x”) I tried this and got a lot of red flags. ---
**Author:** ![Edward\_Ankrom](https://yyz1.discourse-cdn.com/flex031/user_avatar/cl.desmos.com/edward_ankrom/32/8589_2.png) [@Edward\_Ankrom](https://cl.desmos.com/u/Edward_Ankrom)\ **Post date:** [October 21, 2025, 4:31pm UTC](https://cl.desmos.com/t/coding-question/8317/9 "2025-10-21T16:31:09Z")
> [@Daniel\_Grubbs](#): > > y=\frac{5}{2}x-2 This works for non fractions: f1 = simpleFunction(`y=-5x+3`) but I cant code to correct the problems y = 5/2x - 2 I have tried various versions of what people have listed? ---
**Author:** ![Edward\_Ankrom](https://yyz1.discourse-cdn.com/flex031/user_avatar/cl.desmos.com/edward_ankrom/32/8589_2.png) [@Edward\_Ankrom](https://cl.desmos.com/u/Edward_Ankrom)\ **Post date:** [October 21, 2025, 4:39pm UTC](https://cl.desmos.com/t/coding-question/8317/10 "2025-10-21T16:39:37Z")
This is the line of code that works for non fraction answers. f1 = simpleFunction(‘`y=-5x+3`’) ---
**Author:** ![Edward\_Ankrom](https://yyz1.discourse-cdn.com/flex031/user_avatar/cl.desmos.com/edward_ankrom/32/8589_2.png) [@Edward\_Ankrom](https://cl.desmos.com/u/Edward_Ankrom)\ **Post date:** [October 21, 2025, 4:44pm UTC](https://cl.desmos.com/t/coding-question/8317/11 "2025-10-21T16:44:55Z")
Here is my activity > **[Ankrom-Solving Literal Equations • Activity by Amplify Classroom](https://classroom.amplify.com/activity/68f66146e585f0ee457f0f66?utm_campaign=share&utm_content=activity)** > > Practicing Literal Equations ---
**Author:** ![Daniel\_Grubbs](https://yyz1.discourse-cdn.com/flex031/user_avatar/cl.desmos.com/daniel_grubbs/32/719_2.png) [@Daniel\_Grubbs](https://cl.desmos.com/u/Daniel_Grubbs)\ **Post date:** [October 21, 2025, 4:57pm UTC](https://cl.desmos.com/t/coding-question/8317/12 "2025-10-21T16:57:41Z")
The reason it’s not working is the `xTerm` pattern is specifying a number: ```auto xTerm = p.anyOf(X, p.product(p.number,X) , p.negative(X)) ``` Updating it to the following should allow fractional slopes: ```auto pFraction = p.fraction(p.integer, p.integer) xTerm = p.anyOf( X, p.product(p.anyOf(p.number, p.negative(pFraction), pFraction),X), p.negative(X)) ``` (returns are just for readability, but aren’t necessary) ---
**Author:** ![Edward\_Ankrom](https://yyz1.discourse-cdn.com/flex031/user_avatar/cl.desmos.com/edward_ankrom/32/8589_2.png) [@Edward\_Ankrom](https://cl.desmos.com/u/Edward_Ankrom)\ **Post date:** [October 21, 2025, 5:31pm UTC](https://cl.desmos.com/t/coding-question/8317/13 "2025-10-21T17:31:40Z")
Thanks for that info, First time doing an activity builder like this. What lines do I type this on? Just type over the current line? ---
**Author:** ![NTMDev](https://yyz1.discourse-cdn.com/flex031/user_avatar/cl.desmos.com/ntmdev/32/7141_2.png) [@NTMDev](https://cl.desmos.com/u/NTMDev)\ **Post date:** [October 21, 2025, 5:48pm UTC](https://cl.desmos.com/t/coding-question/8317/14 "2025-10-21T17:48:48Z")
Huh? That doesn’t make sense. It should work, but as @Daniel_Grubbs said it is unnecessary Edit: Oh, you need “`” things ---
**Author:** ![NTMDev](https://yyz1.discourse-cdn.com/flex031/user_avatar/cl.desmos.com/ntmdev/32/7141_2.png) [@NTMDev](https://cl.desmos.com/u/NTMDev)\ **Post date:** [October 21, 2025, 5:49pm UTC](https://cl.desmos.com/t/coding-question/8317/15 "2025-10-21T17:49:48Z")
What’s `fraction`, `anyOf`, `product`, or `negative`? Are the `sources`/functions for lists? ---
**Author:** ![Daniel\_Grubbs](https://yyz1.discourse-cdn.com/flex031/user_avatar/cl.desmos.com/daniel_grubbs/32/719_2.png) [@Daniel\_Grubbs](https://cl.desmos.com/u/Daniel_Grubbs)\ **Post date:** [October 21, 2025, 6:15pm UTC](https://cl.desmos.com/t/coding-question/8317/16 "2025-10-21T18:15:46Z")
Those are definitions for patterns, which can be used in an indeterminate number of combinations to analyze and parse latex expressions. Here’s [an intro series](https://cl.desmos.com/t/pattern-matching-basics/5522). ---
**Author:** ![Daniel\_Grubbs](https://yyz1.discourse-cdn.com/flex031/user_avatar/cl.desmos.com/daniel_grubbs/32/719_2.png) [@Daniel\_Grubbs](https://cl.desmos.com/u/Daniel_Grubbs)\ **Post date:** [October 21, 2025, 6:31pm UTC](https://cl.desmos.com/t/coding-question/8317/17 "2025-10-21T18:31:44Z")
> [@Edward\_Ankrom](#): > > What lines do I type this on? > > Just type over the current line? Sorry, missed this one. Yes, just replace the `xTerm` line with the new set of code I provided. Poaching and editing other folks’ code is a great way to jump in and learn! ---
**Author:** ![Edward\_Ankrom](https://yyz1.discourse-cdn.com/flex031/user_avatar/cl.desmos.com/edward_ankrom/32/8589_2.png) [@Edward\_Ankrom](https://cl.desmos.com/u/Edward_Ankrom)\ **Post date:** [October 21, 2025, 6:34pm UTC](https://cl.desmos.com/t/coding-question/8317/18 "2025-10-21T18:34:52Z")
Thanks I got that work. I do have another question. When the first value is an integer and the second is a fraction, do I need to adjust that line? For example if the answer is y = 2x - 3/2 or if the answer has 2 fractions, such as y= 1/2x+ 3/2 ---
**Author:** ![Daniel\_Grubbs](https://yyz1.discourse-cdn.com/flex031/user_avatar/cl.desmos.com/daniel_grubbs/32/719_2.png) [@Daniel\_Grubbs](https://cl.desmos.com/u/Daniel_Grubbs)\ **Post date:** [October 21, 2025, 6:38pm UTC](https://cl.desmos.com/t/coding-question/8317/19 "2025-10-21T18:38:12Z")
Ah yes. Similarly, your `constantTerm` is defined as `p.number` , which includes integers, decimals, and mixed numbers, but not fractions. This is because the fraction pattern is more accurately a rational expression, rather than a number. So we have to similarly include options: ```auto constantTerm = p.anyOf(p.number, p.negative(pFraction), pFraction) ``` ---
**Author:** ![Edward\_Ankrom](https://yyz1.discourse-cdn.com/flex031/user_avatar/cl.desmos.com/edward_ankrom/32/8589_2.png) [@Edward\_Ankrom](https://cl.desmos.com/u/Edward_Ankrom)\ **Post date:** [October 21, 2025, 7:38pm UTC](https://cl.desmos.com/t/coding-question/8317/20 "2025-10-21T19:38:08Z")
If you switch the question to solve for x, do you simply change all xs to ys and vice versa with all the coding? Ed