Derivative | Symbolic Differentiation with Elm | Math library

• I am a new user of Scilab and I am not a mathematician.
• As my end goal, I want to calculate (and plot) the derivative of a piece-wise defined function, see here.
• I tried to start small and just use a simple (continuous) function: f(x) = 3*x.
• My Google-Fu lead me to the numderivative function.
• Problem: It seems that I do not understand how the argument x works since the result is not a 1D-array, instead, it is a matrix.
• Update 1: Maybe I use the wrong function and diff is the way to go. But what is then the purpose of numderivative?

PS: Is this the right place to ask Scilab-related questions? It seems that there are several StackOverflow communities where Scilab-related questions are asked.

I have this code:

Model:

ModelingToolkit.jl is such a great package that I frequently expect too much of it. For example, I often find myself with a model which boils down to the following:

Following is my attempt to create a function to differentiate multivariable functions, but as you see it only seems to be able to differentiate with respect to the first positional argument (namely x). How can I extend this to be able to take partial derivatives with respect to y and z?

I'm wondering if there's any way in python or perl to build a regex where you can define a set of options can appear at most once in any order. So for example I would like a derivative of foo(?: [abc])*, where a, b, c could only appear once. So:

I am writing a small code to calculate the fourth derivative using the method of finite differences in tensorflow. This is as follows:

I think I am close but I would to get your feedback to solve this using a derivative of the code I have already created, I pass the following tests, but I am struggling to pass the final test as I need to return two middle names abbreviated, and at the moment I can only return the first. The tests below show the function and parameters passed, and the expected result its the last ione I am struggling with. I would appreciate your expert advice. Kind regards, Jon

let's say I have several differential equations in the following form

where the variables in the pointed brackets are complex numbers for example

My question is whether it is possible in the Maxima to write down at first the set of the differential equations in the form mentioned above without evaluation the derivatives, then make the substitutions for the variables in the pointed brackets and after that evaluate the derivatives and separate the real and imaginary parts.