FAQ

Frequently asked questions

Welcome to the FAQ section!

Here frequently asked questions are answered, which have come in over time here and may also be of interest to others.

If a question is not answered here, either the page search at the top right will help or a direct mail to the developer.

Legal questions

Does NumeRe cost anything?

No. NumeRe is free software licensed under the GNU GPL v3.

Can I use NumeRe in my own project/can I use parts of the source code?

Yes, as long as the principles of the GNU GPL v3 are respected. A short version of the same can be found in NumeRe itself by typing "about".

How do I cite NumeRe in my publication?

Use the following lines (adjust version number and date if necessary):

Hänel, Erik et al: NumeRe: Framework für Numerische Rechnungen v1.1.4 "Compton". https://www.numere.org, 2022

I want to link NumeRe - May I use the logo?

Yes, as long as the origin of the logo is mentioned/it is used as a clickable image or the logo is not used for another project (due to the risk of confusion), the logo can be used. An example source code of a link can be copied here:

Questions about development

How many developers are involved in NumeRe?

At the moment there are nine of us: Erik Hänel (user interface), Ingo Berg (math parser), Alexey Balakin (plotting & numerical methods), M. Galassi et al. (i.V. for GSL), Joe Coder (i.V. for the Boost Library), Gael Guennabaud and Benoît Jacob (Eigen Library), Lee Thomason (TinyXML-2) and Yap Chun Wei (BasicExcel). And of course all the others who contributed to the libraries involved and cannot be mentioned here.

Is the source code available?

Yes, you can find the source code as SVN repository on SourceForge.

Questions about installation

For which operating systems is NumeRe available?

At the moment only for MS Windows. However, ports are allowed and desired.

What do I have to do to install NumeRe on my own computer?

Since version 1.0.7 NumeRe is released with a full installer. Whether to update file associations of files and NumeRe can be specified during installation.

I want to start NumeRe, but only a cryptic error message appears - what should I do?

If the error message has something to do with a "DLL file", an important program library is missing from your NumeRe distribution. Try to download the latest full version and reinstall it.

If this is not the case or the above solution does not help, send us a mail with the content of your error message and the NumeRe version. We will contact you as soon as possible.

Can NumeRe update itself?

No. This is not possible at the moment. But it can be added in the future. At the moment you just have to install the new version over the old one.

Which version should I use?

Tend to always use the latest stable version. Stable versions are the versions that are named after a physicist and do not have "release candidate" or "rc" in the version name.

Experimenters are welcome to try the latest release candidate and get immediate access to the new features. Mostly these versions are stable enough. If you still encounter bugs: report them to the developer immediately!

Bugs, requests an contribute

I have an idea for a NumeRe functionality - how can I submit it?

Just write a mail with the idea and a description of it to the developer or in the ticket system. We will try to implement the idea as soon as possible.

I have found a bug in NumeRe - how can I submit it?

The best way is to send a mail to the developer or report it in the ticket system. Optimally everything is there to reproduce the error. So a list of the command sequence, the data file, the calculation and the actually expected result, etc.

Since version v1.0.6 "de Broglie" NumeRe creates a logfile (<>/numere.log) of all entered parameters. It's best to send that along.

Why should I report a request or an error?

First of all, because then you can directly participate in the progress of the development and make NumeRe more tailored to your wishes and needs. Apart from that, we all can't find all the small bugs that are simply inevitable.

I want to participate in the development of NumeRe - what do I have to do?

First of all, write a mail to the developer and take a look at the source code. It is also useful to write in the first mail what exactly you want to do, so that the developer can explain the important parts of the source code to you. It might be helpful to visit this site first.

Questions about functionality

Can NumeRe plot functions?

Yes, in many different ways: standard plot (plot and plot3d), grid and surface plot (mesh, mesh3d, surf and surf3d), gradient plot (grad and grad3d), vector field plot (vect and vect3d), density plot (dens and dens3d), contour line plot (cont and cont3d), etc.

I want to plot a data set graphically - Is it possible?

Of course. Depending on whether you have an x-y dataset or an x-y-z dataset, you use plot or plot3d as command. With the additional options xerrorbars, yerrorbars or errorbars you can also display error bars (but your dataset must have more columns). Data that has been converted to a data grid can also be displayed as a 2D representation by mesh, surf, grad, dens and cont.

Load your data into memory and then type, for example, plot data(:,1:2:3) -set yerrorbars to plot the first against the second column and use the values of the third column as error values. You can also plot several data sets at once if you specify them one after the other (e.g. data(:,1:2:3), data(:,7:8:11)).

Can NumeRe create drawings?

Yes. For this purpose the two plot styles draw and draw3d exist. These two styles allow to draw arbitrary geometric objects using special functions.

I miss a plot style!

If your desired plot style can be created by a combination of already existing plot styles, use the "compose ... endcompose" mode.

If this is not possible, then report your wish in the ticket system. It is best to attach a picture of how the plot style should look like.

Can NumeRe export to T_EX?

Yes, tables and plots can be exported to T_EX. For tables, select the "export" parameter and specify a file name with "*.tex" at the end. For plots, select the plot option "otex" with the desired file name. However, it may be advantageous to include plots as images in the T_EX document instead of loading them as TikZ images.

Can NumeRe fit functions to data series?

Yes, you use the command "fit" (or "fitw" if the data contains error values) and specify function (via "-with=FUNC(x,PARAMS)") and parameters to fit (via "-params=[PARAMS=INITIALVALUES]"). NumeRe uses a Levenberg-Marquardt algorithm and also still returns the error values of the adjusted parameters. The results are of course stored in the corresponding variables, so you can directly continue calculating with them.

I have fitted a function to the data series - can I continue calculating with the specific error values?

Yes, in principle. Repeat the fit, additionally passing the parameter -saverr. Then the calculated errors are stored in the PARAM_error variables (where PARAM denotes the variable names of the paramters).

Can NumeRe Fourier transform data?

Yes, NumeRe is equipped with a fast Fourier transform algorithm. This is started with the command "fft". By default, NumeRe returns the results for amplitude and phase, but this can be changed to real and imaginary parts by "-complex".

I have a composite function or expression that I use frequently. Can NumeRe store it?

Yes, NumeRe can store an indefinite amount of user-defined functions. These functions can have up to 10 arguments. The functions can be defined using the "define" command and saved using "define -save".

I have a frequently used or complex command sequence. Can I automate or cache them somehow?

Yes, command and calculation sequences can be swapped out into NumeRe scripts that can be called easily and repeatedly.

Can I extend the functionality of NumeRe?

Yes, through the plugins mentioned below or through procedures if no explicit user interface is required.

Questions about file formats

What file formats can be read with NumeRe?

NumeRe can read text files with space- or tab-delimited columns, CASSYLab files (*.labx), JCAMP DX files (*.jdx, *.dx or*.jcm), IGOR binary wave files (*.ibw), CSV files (*.csv) and Excel workbooks (*.xls and *.xlsx) (as long as they are structured column-wise). In addition, of course, NumeRe's own formats "NumeRe data file" (*.ndat), "NumeRe script" (*.nscr) and "NumeRe procedure" (*.nprc).

I have a special format of a text file. Can I still open it in NumeRe?

Yes, if the file is a plain text file, it can be read by "read" as well. The file will be read line by line as strings and can be saved directly into the string() object if necessary.

I need a special format of a text file. Can I create it in NumeRe?

Yes. The "write" command allows writing strings to text files. The strings to be written can be formatted appropriately beforehand.

I want to open a NumeRe data file with a text editor - why can't I recognize anything?

NumeRe data files are binary files, which can be written and read faster than text files. To view the data, it must be opened with NumeRe (and exported as a text file if necessary).

Questions about extensions (Plugins)

What is a plugin?

Plugins are extensions to NumeRe written in NumeRe's own procedure/script language. These plugins add more functionality to NumeRe or combine existing functionality.

How do I install a plugin?

Plugins come in the form of a NumeRe script that contains "<install>...<endinstall>" tags. To install the plugin, the script must be executed within NumeRe using the "install" command:

install SCRIPTNAME

How do I remove a previously installed plugin?

Plugins can be removed using the "uninstall" command. "uninstall" expects the plugin name (and not the command). The names of the plugins are shown in square brackets at "list -plugins".

I have written a plugin and want to make it available to others - what can I do?

You can find the necessary instructions on the corresponding project page on SourceForge. You also need a SourceForge account so that we can give you the necessary write permissions.