9.16.1 Top new questions this week

9.16.1.1 How to combine several legends in one frame?
9.16.1.2 Show steps in finding the reduced row echelon form of a symbolic matrix
9.16.1.3 How to determine whether a point is within a multidimensional degenerate convex hull?
9.16.1.4 Fill rainbow along vertical axis
9.16.1.5 Passing negative parameters to a wolframscript
9.16.1.6 Extracting arguments from a list of function calls
9.16.1.7 Solving a system of three complex equations
9.16.1.1 How to combine several legends in one frame?

https://mathematica.stackexchange.com/landing/r/digest?cta=question&id=284456

I'm using  Show  to combine three plots. The code I write is as follows: 
... 
[plotting] [graphics] [legending] [frame]
 
asked by Ya He https://mathematica.stackexchange.com/landing/r/digest?cta=user&id=89117 Score of 6
answered by kglr https://mathematica.stackexchange.com/landing/r/digest?cta=user&id=125 Score of 6
9.16.1.2 Show steps in finding the reduced row echelon form of a symbolic matrix

https://mathematica.stackexchange.com/landing/r/digest?cta=question&id=284439

I would like to figure out a way to see the row operations  RowReduce  uses to arrive at the reduced row echelon form of a symbolic square matrix. 
Solutions that show ... 
[matrix] [linear-algebra]
 
asked by granular bastard https://mathematica.stackexchange.com/landing/r/digest?cta=user&id=69288 Score of 6
answered by Nasser https://mathematica.stackexchange.com/landing/r/digest?cta=user&id=70 Score of 8
9.16.1.3 How to determine whether a point is within a multidimensional degenerate convex hull?

https://mathematica.stackexchange.com/landing/r/digest?cta=question&id=284553

There are two set of points 
... 
[geometry] [computational-geometry] [convexhull]
 
asked by lapcal https://mathematica.stackexchange.com/landing/r/digest?cta=user&id=85338 Score of 5
answered by flinty https://mathematica.stackexchange.com/landing/r/digest?cta=user&id=72682 Score of 8
9.16.1.4 Fill rainbow along vertical axis

https://mathematica.stackexchange.com/landing/r/digest?cta=question&id=284547

 Plot[x^2, {x, -2, 2}, Filling -> {1 -> Top}, 
FillingStyle -> Automatic, 
ColorFunction -> {Function[{x, y}, ColorData["Rainbow"][4 y]]}] 
 
... 
[plotting] [graphics] [color] [filling]
 
asked by user84456 https://mathematica.stackexchange.com/landing/r/digest?cta=user&id=84456 Score of 5
answered by banone https://mathematica.stackexchange.com/landing/r/digest?cta=user&id=66293 Score of 9
9.16.1.5 Passing negative parameters to a wolframscript

https://mathematica.stackexchange.com/landing/r/digest?cta=question&id=284506

How do you pass negative values as input for a  wolframscript ? 
This documentation page explains that the syntax for passing parameters is: 
... 
[scripting]
 
asked by mattiav27 https://mathematica.stackexchange.com/landing/r/digest?cta=user&id=8822 Score of 5
answered by mattiav27 https://mathematica.stackexchange.com/landing/r/digest?cta=user&id=8822 Score of 3
9.16.1.6 Extracting arguments from a list of function calls

https://mathematica.stackexchange.com/landing/r/digest?cta=question&id=284495

Suppose I have some list like the following form 
$ \{ j[two, 1,1,1,1], j[two,2,2,2,2], j[two,3,3,3,3] \}$ 
... 
[list-manipulation]
 
asked by phy_math https://mathematica.stackexchange.com/landing/r/digest?cta=user&id=49075 Score of 5
answered by kglr https://mathematica.stackexchange.com/landing/r/digest?cta=user&id=125 Score of 7
9.16.1.7 Solving a system of three complex equations

https://mathematica.stackexchange.com/landing/r/digest?cta=question&id=284662

Consider the following quantities: 
... 
[equation-solving] [matrix]
 
asked by Rob https://mathematica.stackexchange.com/landing/r/digest?cta=user&id=66809 Score of 4
answered by Bill https://mathematica.stackexchange.com/landing/r/digest?cta=user&id=18890 Score of 1