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hddd123456789
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Holy...I have to retype my entire post *sigh* lovely.
Ok, let's try a shorter version. I've had a question that my engineering cousin was unable to help me with (perhaps too busy). I'm a programmer first, and barely remember Calculus I so we're both on the same page.
Let's start with y=x. If we subtract x from both sides, we get y-x=0. Ok, but let's generalize this. Let's recognize that y=x is the same as y=f(x), so we may rewrite y-f(x)=0. Ok, now generalizing further, let's say g(x,y)=y-f(x). There's a particular reason why I made this formulation (though I originally never bothered to formalize it to as much as I've done here).
First off, a simple algorithm for graphing a 2D function might go something like this: you get the position of the current x position on the graph that you are, well, graphing, and run that through f(x), get the y value, and then plot a line from the last point to the new point, and repeat until you have graphed the whole curve.
Now, being a programmer, a thought occurred to me: what if you went in reverse? What if you went pixel by pixel, and instead of calculating f(x), you use the x,y coordinates for that pixel and calculate g(x,y) as per two paragraphs above. So instead of, for example, calculating f(x)=x^2 for a particular x coordinate, you would instead calculate g(x,y)=y-x^2 for a point represented by a pixel on the image. The value that you get for g(x,y) would in turn be expressed as brightness on a grayscale "plot" of the graph. As far as I can tell, this really just amounts to a 3D plot of our standard 2D functions.
So finaaaly, (just copied post) here's the question: what do the attached graphs mean exactly? The typical curve that we are used to would lie where the bright regions lie in these graphs. What's interesting to me is noting the nodes in the graphs, particularly the sin(x) and ln(x) curves. What really get's me is that in all the graphs, there're these "ghostly" shades under/side of the traditional curves. It is most clearly apparent in y=x^2, where you can see (if your brightness/contrast is high enough) a dark "shadow" looking thing under the parabola. Am I correct in thinking this has something to do with imaginary numbers? Either that, or it seems to almost be some sort of probability curve for the 2D function, as if f(x)=x^2 only shows the curve where there exists a 100% probability of a point existing on it. On the other hand, the 3d graphs perhaps show the full gradient of probabilities for every point on the functional grid?
Well, I could keep going, but I'll wait for some feedback. I'll attach more in the next post, but for now, from left to right is the Gaussian y=e^-(x^2), y=ln(x), and y=x^2.)
Ok, let's try a shorter version. I've had a question that my engineering cousin was unable to help me with (perhaps too busy). I'm a programmer first, and barely remember Calculus I so we're both on the same page.
Let's start with y=x. If we subtract x from both sides, we get y-x=0. Ok, but let's generalize this. Let's recognize that y=x is the same as y=f(x), so we may rewrite y-f(x)=0. Ok, now generalizing further, let's say g(x,y)=y-f(x). There's a particular reason why I made this formulation (though I originally never bothered to formalize it to as much as I've done here).
First off, a simple algorithm for graphing a 2D function might go something like this: you get the position of the current x position on the graph that you are, well, graphing, and run that through f(x), get the y value, and then plot a line from the last point to the new point, and repeat until you have graphed the whole curve.
Now, being a programmer, a thought occurred to me: what if you went in reverse? What if you went pixel by pixel, and instead of calculating f(x), you use the x,y coordinates for that pixel and calculate g(x,y) as per two paragraphs above. So instead of, for example, calculating f(x)=x^2 for a particular x coordinate, you would instead calculate g(x,y)=y-x^2 for a point represented by a pixel on the image. The value that you get for g(x,y) would in turn be expressed as brightness on a grayscale "plot" of the graph. As far as I can tell, this really just amounts to a 3D plot of our standard 2D functions.
So finaaaly, (just copied post) here's the question: what do the attached graphs mean exactly? The typical curve that we are used to would lie where the bright regions lie in these graphs. What's interesting to me is noting the nodes in the graphs, particularly the sin(x) and ln(x) curves. What really get's me is that in all the graphs, there're these "ghostly" shades under/side of the traditional curves. It is most clearly apparent in y=x^2, where you can see (if your brightness/contrast is high enough) a dark "shadow" looking thing under the parabola. Am I correct in thinking this has something to do with imaginary numbers? Either that, or it seems to almost be some sort of probability curve for the 2D function, as if f(x)=x^2 only shows the curve where there exists a 100% probability of a point existing on it. On the other hand, the 3d graphs perhaps show the full gradient of probabilities for every point on the functional grid?
Well, I could keep going, but I'll wait for some feedback. I'll attach more in the next post, but for now, from left to right is the Gaussian y=e^-(x^2), y=ln(x), and y=x^2.)