Loading packages
- To: mathgroup at smc.vnet.net
- Subject: [mg9516] Loading packages
- From: Steven Wilkinson <wilkinson at NKU.EDU>
- Date: Sat, 8 Nov 1997 23:04:43 -0500
- Sender: owner-wri-mathgroup at wolfram.com
Mathgroup, I have a problem that I have seen pop up on this list from time to time, but I can't make any of the answers that have appeared work. I can't load the packages I write into Mathematica 3.0 with either Get or Need. One response I saw was given in the following message: >If you are using Mathematica 3.x, you can do one of the following: > > 1) Declare the cell containing the package commands to be an > initialization cell. Highlight the cell, then from the Menu commands > select: "Cell", "Properties", "Initialization". Now save the > notebook and when the popup menu says "Auto Save Package" respond with > "Create Auto Save Package". Mathematica will automatically save a copy of the > initialization cell as a package with the .m file extension. > > OR > > 2) Save the notebook as a package file. You have to manually type in > the file name with the .m file extension in the dialog box > window--selecting the package file type from the drop down menu won't > do it. This method should work in pre Mathematica 3.x versions. But I found > that in some instances with pre Mathematica 3.x versions, there was a bug in > the notebook frontend and it was best just to write the package in a > standard text editor and save it with the .m file extension. > > Dave Harvatin > > On 31 Jul 1997 03:49:25 GMT, "jmt" <jmt at cybercable.tm.fr> wrote: > >>If I write a package, say >> >>BeginPackage["myPackage`"] >>f::usage="f does strictly nothing" >>Begin["Private`"] >>f[_]=Null >>EndPackage[] >>End[] >> >>using an ordinary notebook, I will have to save it, let's say myPackage.nb >>If I read this notebook, using << or Get, the content of the file is not >>evaluated: no "myPackage`" context is happened to $ContextPath. >> >>It I use the command File->Save As Special->Package Format, I'm not asked >>wether I want the file to be either .nb or .m, the standard is .nb I followed instruction set (2) on the above package. When I issued the Get command <<myPackage.m Mathematica responded with the error message Get : : Noopen : Cannot open myPackage.m. What am I doing wrong? Does this error message mean it couldn't find the file "myPackage.m" or that once it found it it couldn't do anything with it? In another response to a similar question that dealt with the Needs command, David Withoff said >The Needs::nocont message is generated when Needs["context"] finds that >"context" is not present in the value of $Packages. Since "context" is >prepended to $Packages as one of the first steps in evaluation of >BeginPackage["context"], the appearance of this message usually means >that BeginPackage["context"] hasn't been evaluated. The first thing >that I would do to solve this problem would be to take a close look at >the .m file with an ordinary text editor. What am I looking for? Steve Wilkinson Northern Kentucky University