vonjd
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 Jul24 comment What are some conceptualizations that work in mathematics but are not strictly true? That is better :-) Jul24 comment What are some conceptualizations that work in mathematics but are not strictly true? But you didn't say that a line has to be straight. Jul24 comment What are some conceptualizations that work in mathematics but are not strictly true? Whether this is true or not depends on the axiomatic system and how you define "line". Jul2 awarded Curious Jul2 awarded Inquisitive Jun4 awarded Notable Question May22 comment What's going on in Ito calculus? Could you tell us which books did you find and what exactly is missing there? May16 asked Why do you need an integral to invert the Z-Transform? May15 awarded Necromancer May15 comment Example for finite dimensional analog of integral transforms I tried this with Mathematica and the vector $\{1,2,3,4,5\}$. The result after multiplying with $B(z)$ and transforming back should be $\{1,1,1,1,1\}$ because these are the first differences, right? (I am not sure about the last one, but anyway). Interestingly after multiplying with $B(z)$ I get $\{1,2,3,4,5\}$ and transforming this back gives the discrete delta function times $\{1,2,3,4,5\}$: wolframalpha.com/input/… - what's wrong?!? May15 comment Example for finite dimensional analog of integral transforms This is exactly what I was looking for! Thank you very much indeed! :-) May15 accepted Example for finite dimensional analog of integral transforms May14 comment Example for finite dimensional analog of integral transforms @MattL. Ok, I tried this with vectors but there are still things that don't work out :-( If you gave me an example with the z-transform on vectors where multiplication/division becomes differentiation/integration I would happily accept your answer :-) Thank you May14 reviewed Approve Why does $\sin(0)$ exist? May14 comment Discrete Laplace Tranform. I asked a similar question here: math.stackexchange.com/questions/793550/… - what I find strange though is that while you can also read that the Laplace transform is the continuous analog of the dot product for infinite dimensional vectors (=functions) you still calculate infinitely many terms in the discrete version (and not just over the available dimensions of your vectors as with the dot product) - perhpas you could contribute :-) May14 comment Discrete Laplace Tranform. I asked a similar question here: math.stackexchange.com/questions/793550/… - what I find strange though is that while you can also read that the Laplace transform is the continuous analog of the dot product for infinite dimensional vectors (=functions) you still calculate infinitely many terms in the discrete version (and not just over the available dimensions of your vectors as with the dot product) - perhpas you could contribute :-) May14 comment Example for finite dimensional analog of integral transforms @MattL.: Thank you, what still bothers me with this finite version is that the sum is over infinitely many terms because the dot product is only over the available dimensions. May13 reviewed Approve Trigonometric substitution May13 comment Example for finite dimensional analog of integral transforms @MattL.: I had a quick look at it and it looks promising - so first thank you! Could the $z$ also be real valued like e.g. $2$? May13 comment Example for finite dimensional analog of integral transforms @MattL.: To be honest with you I don't know because I don't know the Z-transform well enough. But perhaps you could give an example that contains the elements I asked for in my question?