2.27.3 Can you answer these questions?

2.27.3.1 Computations with OptimizedExpressions without completely expanding them

https://mathematica.stackexchange.com/landing/r/digest?cta=question&id=221938

I have to manipulate huge expressions that are rational functions of many (30) variables with integer coefficients. Storing them just as a ratio of two polynomials would be impractical. But they can ...

asked by Vladimir Reshetnikov https://mathematica.stackexchange.com/landing/r/digest?cta=user&id=7288 2 votes

2.27.3.2 LeviCivitaTensor contraction indices

https://mathematica.stackexchange.com/landing/r/digest?cta=question&id=222179

apparently my computer has problems when I try to perform a calculation with TensorContract.

In particular, with the second answer to my previous question Contracting indices in lists, I want to ...

asked by FB20 https://mathematica.stackexchange.com/landing/r/digest?cta=user&id=72314 1 vote

2.27.3.3 Using Fold[ or Map[ Better?

https://mathematica.stackexchange.com/landing/r/digest?cta=question&id=221941

I’m working through MMA Cookbook by Mangano, page 54. He shows Map is a compact form of Fold function. Is using Fold function important?

myMap3[f_, l_] := Fold[Prepend[#1, f[#2]]&, {}, l]

asked by code9910743 https://mathematica.stackexchange.com/landing/r/digest?cta=user&id=59860 2 votes