Find Inverse Tangent?

Question

I'm new to Javascript and I'm trying to use inverse tangent to find the angle in degrees between a line and the x axis on an elevated y. I don't see any command for it so I really need some help.

Solution

Use Math.atan() function and then Math.toDegrees() multiply it by 180/Math.PI to convert radians to degrees Found the answer it here

Later edit:

Here is an example of angle calculation between a line defined by 2 points (A and B) and the X axis. The elevation of the second line (parallel with the X axis) is irrelevant since the angle stays the same.

 /*
 * Calculates the angle between AB and the X axis
 * A and B are points (ax,ay) and (bx,by)
 */
function getAngleDeg(ax,ay,bx,by) {
  var angleRad = Math.atan((ay-by)/(ax-bx));
  var angleDeg = angleRad * 180 / Math.PI;
  
  return(angleDeg);
}

console.log(getAngleDeg(0,1,0,0));

Comments

[PLP123]

what do I put into the atan? is it all 3 x's and y's

[Da Mahdi03]

This is from ProcessingJS, not JavaScript, there is a difference!

[Kevin Workman]

@DaMahdi03 Yes, I know. Please notice the processing.js tag in the question.

[Da Mahdi03]

Maybe the person writing the question didn't know too much about JavaScript?

[Kevin Workman]

@DaMahdi03 Sorry, I'm not sure what you're trying to tell me. The question was tagged with processing.js, so I answered with Processing.js. Seems pretty reasonable to me.