p5.js斜率函数疑似报错问题求助（再次咨询）

Hey there, let's figure out why your slope function might be throwing errors. Looking over your code, I've spotted a couple of key issues that could be causing problems, plus some tweaks to make it more robust:

Potential Error Sources #

• Division by Zero Risk: If x1 and x2 are the same (a vertical line), gg1 = x2 - x1 becomes 0. Dividing gg2 by 0 will result in Infinity or NaN, which breaks the function's return value and clogs your console.
• Unhandled Direction Values: Your function only checks for "right" and "left". If you pass an invalid string (or forget to pass direction entirely), the function will return undefined with no feedback—super confusing when debugging!
• Redundant Code: You calculate ggsR = gg1/gg2 and log it, but never use this variable. It doesn't cause errors, but it adds unnecessary clutter.

Fixed Version of Your Code #

Here's an updated version that addresses all these issues:

function graphY(num, cHI){ 
  var GsetR = cHI - num; 
  return GsetR; 
}; 

function slope(x1, y1, x2, y2, ex, direction){ 
  // Handle vertical lines first to avoid division by zero
  if(x1 === x2){
    console.warn("Vertical line detected—slope is mathematically undefined");
    return Infinity; // Or return undefined if that fits your use case better
  }
  
  var gg1 = x2 - x1; 
  var gg2 = y2 - y1; 
  var ggs = gg2 / gg1; 

  // Use switch for cleaner direction handling + default case
  switch(direction){
    case "right":
      return ggs;
    case "left":
      return -ggs;
    default:
      console.warn(`Invalid direction: "${direction}"—using "right" as default`);
      return ggs;
  }
}; 

function setup() { 
  createCanvas(1000,650);
  // ... rest of your setup code here
}

Key Fixes Explained #

• Vertical Line Handling: We check if x1 equals x2 upfront, log a warning, and return a clear value (Infinity) instead of letting the division fail silently.
• Robust Direction Checks: The switch statement makes direction logic easier to read, and the default branch ensures the function always returns a value—even if you pass a bad input.
• Cleaned Redundant Code: Removed the unused ggsR variable and its log to keep the function focused.

Test this with edge cases (like vertical lines or typos in direction) and check your console—you'll get helpful warnings instead of mysterious errors!

内容的提问来源于stack exchange，提问作者Coding King2