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Here is an example of how to do it. We need xTensor and xCoba packages. First is made to work with abstract objects, whilst the second is for operations with explicitly specified metric and basis: << xAct`xTensor` << xAct`xCoba`(*Package*) Then comes an example of how to define and get all the quantities for Kerr metric. In your case you ...


2

I don't have a general approach but in a world where 19 and x^4+23 define our number field, a decomposition can be found by factoring the polynomial. InputForm[Factor[x^4+23,Modulus->19]] (* Out[3]//InputForm= (2 + 2*x + x^2)*(2 + 17*x + x^2) *) The upshot is that the ideal <19,x^4+23> in Z[x] is the ...


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Because MonoIntervals[f[x],x] will evaluate like this: MonoIntervals[f[x], x] MonoIntervals[x^2+2*x-10, x] And it stops there because x^2+2*x-10 doesn't match the pattern func_[arg_]. What precisely are you trying to achieve by using this pattern?


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It appears that 1879 is correct. Cofactor[a,{1,1}] is equivalent to Det[a[[2 ;;, 2 ;;]]], which is 1879. More generally, Cofactor[a,{i,j}] is equivalent to Det[Drop[a, {i}, {j}]]*(2*Mod[i*j, 2] - 1) The second term here accounts cofactors for the fact that the even positions of odd rows (and the odd positions of even rows) are the negative of the ...


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The book A Mathematical Introduction to Robotic Manipulation talks about kinematic and dynamic modeling for manipulators based on Screw theory. It provides a Mathematica Package for Screw Calculus. I find it quite useful.



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