Skip to main content

What is the purpose of tags like :Name:, :Context:, etc. in packages?


I noticed that all of the packages that come with Mathematica start with a header that is in a standard format. (See e.g. the header of NIntegrateUtilities` at the end.)


There are several commented sections, each starting with a word surrounded by colons.


Question: What is the purpose of these colon-surrounded words? Do they have any meaning to Mathematica? They look like they were made for a machine to parse. Does Mathematica have any functions/tools that can read these?



(* :Name: NIntegrateUtilities` *)


(* :Title: Utility functions for NIntegrate. *)

(* :Author: Anton Antonov *)

(* :Summary:
 This package provides a number of supporting functions for NIntegrate.
*)

(* :Context: DifferentialEquations`NIntegrateUtilities` *)


(* :Package Version: 1.0 *)

(* :Copyright: Copyright 2007, Wolfram Research, Inc. *)

(* :History:
 Version 1.0 by Anton Atnonov, March 2007.
*)

(* :Keywords:
 NIntegrate, integration, evaluations, profiling.

*)

(* :Source:
*)

(* :Mathematica Version: 6.0 *)

(* :Limitation:
*)


(* :Discussion:
*)


Answer



Old versions of Mathematica featured the package Utilities`Package`. This had the function Annotation[] that read those commented lines in packages so that one could see those annotations without having to explicitly open those packages in the front end.


Needs["Utilities`Package`"]

Annotation["Statistics`NonlinearFit`"]
{"Title", "Context", "Name", "Author", "Summary", "Copyright", "Package Version", "Mathematica Version", "History", "Keywords", "Sources", "Discussion", "Warning", "Example", "Example", "Example"}


Annotation["Statistics`NonlinearFit`", "Mathematica Version"]
{"(* :Mathematica Version: 5.0 *)"}

If you want to still use this function, it's available here. I would say those specific delimiters allowed the package to pick out annotations instead of code comments.


Comments

Post a Comment

Popular posts from this blog

functions - Get leading series expansion term?

Given a function f[x] , I would like to have a function leadingSeries that returns just the leading term in the series around x=0 . For example: leadingSeries[(1/x + 2)/(4 + 1/x^2 + x)] x and leadingSeries[(1/x + 2 + (1 - 1/x^3)/4)/(4 + x)] -(1/(16 x^3)) Is there such a function in Mathematica? Or maybe one can implement it efficiently? EDIT I finally went with the following implementation, based on Carl Woll 's answer: lds[ex_,x_]:=( (ex/.x->(x+O[x]^2))/.SeriesData[U_,Z_,L_List,Mi_,Ma_,De_]:>SeriesData[U,Z,{L[[1]]},Mi,Mi+1,De]//Quiet//Normal) The advantage is, that this one also properly works with functions whose leading term is a constant: lds[Exp[x],x] 1 Answer Update 1 Updated to eliminate SeriesData and to not return additional terms Perhaps you could use: leadingSeries[expr_, x_] := Normal[expr /. x->(x+O[x]^2) /. a_List :> Take[a, 1]] Then for your examples: leadingSeries[(1/x + 2)/(4 + 1/x^2 + x), x] leadingSeries[Exp[x], x] leadingSeries[(1/x + 2 + (1 - 1/x...
Post a Comment
Read more

mathematical optimization - Minimizing using indices, error: Part::pkspec1: The expression cannot be used as a part specification

I want to use Minimize where the variables to minimize are indices pointing into an array. Here a MWE that hopefully shows what my problem is. vars = u@# & /@ Range[3]; cons = Flatten@ { Table[(u[j] != #) & /@ vars[[j + 1 ;; -1]], {j, 1, 3 - 1}], 1 vec1 = {1, 2, 3}; vec2 = {1, 2, 3}; Minimize[{Total@((vec1[[#]] - vec2[[u[#]]])^2 & /@ Range[1, 3]), cons}, vars, Integers] The error I get: Part::pkspec1: The expression u[1] cannot be used as a part specification. >> Answer Ok, it seems that one can get around Mathematica trying to evaluate vec2[[u[1]]] too early by using the function Indexed[vec2,u[1]] . The working MWE would then look like the following: vars = u@# & /@ Range[3]; cons = Flatten@{ Table[(u[j] != #) & /@ vars[[j + 1 ;; -1]], {j, 1, 3 - 1}], 1 vec1 = {1, 2, 3}; vec2 = {1, 2, 3}; NMinimize[ {Total@((vec1[[#]] - Indexed[vec2, u[#]])^2 & /@ R...
Post a Comment
Read more

plotting - Plot 4D data with color as 4th dimension

I have a list of 4D data (x position, y position, amplitude, wavelength). I want to plot x, y, and amplitude on a 3D plot and have the color of the points correspond to the wavelength. I have seen many examples using functions to define color but my wavelength cannot be expressed by an analytic function. Is there a simple way to do this? Answer Here a another possible way to visualize 4D data: data = Flatten[Table[{x, y, x^2 + y^2, Sin[x - y]}, {x, -Pi, Pi,Pi/10}, {y,-Pi,Pi, Pi/10}], 1]; You can use the function Point along with VertexColors . Now the points are places using the first three elements and the color is determined by the fourth. In this case I used Hue, but you can use whatever you prefer. Graphics3D[ Point[data[[All, 1 ;; 3]], VertexColors -> Hue /@ data[[All, 4]]], Axes -> True, BoxRatios -> {1, 1, 1/GoldenRatio}]
Post a Comment
Read more