Recent content by pjhphysics

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    Quaternions and rotation vector.

    What constitutes the vector part of the quaternion?
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    Quaternions and rotation vector.

    Hi, I'm trying to calculate a normalized 3d vector representing the quaternion's orientation. Can anyone give me a hand? Thanks!
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    Calculate coordinate in 3D triangle.

    That does it. Thanks a ton
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    Calculate coordinate in 3D triangle.

    Hi, I'm looking for an efficient way of achieving the following, but having trouble thinking it through: Let's say I have a triangle in three dimensions with vertices A, B and C. Let's say I also have a three dimensional coordinate D. I know the x and z component values for D and I am...
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    Find Scalene Non-Right Triangle 3rd Point w/ Side Lengths & Coordinates

    Yes, so I have to find the intersection of two circles. How is this achieved?
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    Find Scalene Non-Right Triangle 3rd Point w/ Side Lengths & Coordinates

    If I know the length of all three sides of a triangle and the coordinates of two of those points, how can I find the coordinates of the third point (in a scalene non-right triangle)? Thanks
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    Is nlogn the Same as n Multiplied by logn?

    Hey, Is nlogn (or more specifically nlog[base2]n) the same as: n multiplied by logn? Thanks
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    How can I improve this equation to work in all cases?

    Hi, Thanks for the help. I derived the following, which seems to work in some but not all cases. In cases where it doesn't work, it seems that the signs of Cx and Cy are the opposite of what they should be, which makes me think I need to put in an absolute value notation somewhere in my...
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    How can I improve this equation to work in all cases?

    Hey, thanks for your help. What exactly is the form of this linear formula? I'm not sure I understand how to set this up. Could you provide a demonstration please (or point me to one)? Thanks so much.
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    How can I improve this equation to work in all cases?

    Hi, Let's say I have two points: Pa = (0, 0, -30) Pb = (-2.5, -2.5, 7.5) and I want to find the X and Y values for a third point on this line whose Z value is 30: Pc = (X, Y, 30) How can I achieve this? My math is not very great and I'm applying this to a computer program. So...
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    Special Relativity and Reference Frames

    Let me give context for my question: In an essay that is only partially about physics, I am trying to show that we cannot think of an object's state without taking the role of the observer into consideration. For example, if we have a light bulb that is sometimes on and sometimes off, and we ask...
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    Special Relativity and Reference Frames

    Quoting DaleSpam, "Either way, the time of the reception event is never considered to be the time of the emission event." So, under what circumstances would the observer have an effect upon the time of the emission event? My point in this inquiry is to consider how the state of the observer...
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    Special Relativity and Reference Frames

    Thank you for response, So here is a revised version... Light bulb, Observer A and Observer B are in the same reference frame F. Light bulb is switched on at 11:00:00. Observer A sees light bulb go on at 11:00:01 Observer B sees light bulb go on at 12:00:00 If neither observer compensated their...
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    Special Relativity and Reference Frames

    Thanks for your response. I see your point that this is not really an issue of special relativity. For clarity, may I pursue this question a bit further with the understanding that this question is no longer an issue of SR? As you say, "all observers who are at rest wrt each other will agree on...
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