22. 1D State Vector and More Multiplication
Matrix Multiplication
Let's walk through that last quiz example, step-by-step.
- Multiply the first row by the first column and sum.
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- Then, the second row, by the first column.
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- Then back to the first row, this time, multiplied by the second column.
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And, finally the last step:
- The last row multiplied by the last column.
To get our complete, resulting matrix!
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Constant velocity
This kind of multiplication can be really useful, if x and y are not dependent on one another. That is, there is a separate and constant x-velocity and y-velocity component. For real-world, curved and continuous motion, we still use a state vector that is one column, so that we can handle any x-y dependencies. So, you'll often see state vector and transformation matrices that look like the following.
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State vector equivalent
These extra spaces in the matrix allow for more detailed motion models and can account for a x and y dependence on one another (just think of the case of circular motion). So, state vectors are always column vectors.