# Files

Abstract

Simfit can accept data from the clipboard, from tables with or without row and column labels (in tab-, comma-, semicolon-, space-delimited formats, or as .xml, .html, .htm, .mht, .mhtml files), as well as from data files in Simfit format.

You can transfer data tables directly from spreadsheet programs into SIMFIT programs by selecting columns and copying to the clipboard, and you can make correctly formatted files by pasting such clipboard data tables into program MAKSIM. There are also Excel macros (*.XLS) provided with the SIMFIT package to enable you to create correctly formatted files from Microsoft Office, but SIMFIT also has a suite of editors to facilitate the creation and editing of data files. For instance, program MAKFIL has many special features to help you create correctly formatted data files for curve fitting, but program MAKMAT should be used to generate data files for statistical analysis. Program SIMPLOT can be used to make graphics files while program MAKLIB is used to collect the names of groups of files together into a library file for simultaneous plotting or statistical analysis. Program MAKSIM takes in data in tabular form as an ASCII text file or from clipboard data copied from a spreadsheet in order to select rows and columns then generate a data file in the SIMFIT format. SIMFIT data files can be viewed in the SIMFIT viewer or using any text editor, e.g. NOTEPAD.

Details

It is a very bad policy to type data into programs for direct analysis since you will almost always want to save the data to edit or re-use. For this reason, always make data files. You can make these by typing your data values directly into the appropriate program or by copying from your spreadsheet program to the clipboard and pasting into a program (MAKSIM) to generate correctly formatted data files. All SIMFIT programs will allow you to paste in data directly from the clipboard but this is not recommended. SIMFIT data files are ASCII text files that have a very simple format, which will easily be appreciated if you browse any test file *.tf? (e.g. MMFIT.TF1) in the viewer.

All the values in SIMFIT data files must be numerical, but any format can be used, e.g. 100, 100.0, 1.0E2, 1.0E+02, and the columns of numbers can be separated by tabs, semicolons (or spaces, or commas as long as commas are not used for decimal points). Any files not consistent with this format will be rejected with an error message telling you what is wrong.

SIMFIT data files contain the numerical data required for curve fitting, statistical analysis or plotting, but obviously data must be formatted correctly. For example differential equations are solved sequentially, so the x-values must be in increasing order. Again, weights for fitting must be sensible positive values, and such restrictions are built into SIMFIT editors.

The format for SIMFIT data files `Title (i.e. identifier for the data) m n (i.e. no. rows no. columns in the data set) ... data (i.e. the m by n matrix) ... data ... data k (i.e. the no. of further text lines) ... text (i.e. extra lines of text)`

You can use any editor to make such files but you are likely to make mistakes and produce a file that is read incorrectly or not at all. For this reason you should always use the SIMFIT editors to prepare or edit your data files.

Copying data from SIMFIT to the clipboard

At various points in SIMFIT you will be able to use the editor in view-only mode. For example after doing statistical analysis or curve fitting, or by selecting the View Text option. If you select text when in this mode it can be copied to the clipboard in the usual way. This is most useful when selecting a part of a data set or a section from a results file to include in a document. Also note that tables of data copied from the SIMFIT viewer can be pasted into other applications.

Copying graphs from SIMFIT to the clipboard

Each time SIMFIT displays a graph there is a Copy button which allows you to copy the current graph to the clipboard. However you should note that all that is copied is a bitmap of the display which, being essentially a .bmp file, will be large and of poor resolution. This is not the best way to use SIMFIT graphics, even though it may be convenient. The best way is to save the graph in the .eps format since such vector files are very small and of much higher quality. You can easily print the .eps file or transform it into a graphics file using the built-in options to transform *.eps files using the GhostScript dll distributed with SIMFIT.

Copying numerical data from the clipboard into SIMFIT

Each time SIMFIT requests you to input data for analysis it looks to see what sort of data are on the clipboard. If there are ASCII text data, then the Paste button will become activated and you can paste data into a temporary file for analysis. If the first clipboard data line is numerical, SIMFIT will attempt to generate a data file with a header and trailer, just like any normal SIMFIT data file. For instance, if you paste two columns from your spreadsheet onto the clipboard you will then be able to plot them or fit them. If the result is interesting you can save the temporary file f$??????.tmp with a chosen file name, since SIMFIT ignores and (usually) deletes such temporary data files. Note that to do this you paste selected columns of numerical data with no labels. This is the rule: if there only numbers on the first clipboard line, SIMFIT will try to create a data file.

Pasting arbitrary data from the clipboard into SIMFIT

You can leave all labels and character data in the table if you want to use MAKSIM for data extraction, but note that MAKSIM regards spaces as separators, so use labels like Mr_John_Smith, etc.

Advice about creating SIMFIT data files

- Use an informative title with the date of the experiment.
- The first additional text line after the end of the data controls some programs, e.g. CALCURVE in expert mode, but most programs ignore the text. This is where you enter details of your experiment for posterity. However, the use of several advanced programs is greatly facilitated by provided by the trailer section. For instance, starting estimates for constrained curve fitting by program QNFIT using the expert mode.
- When using MAKFIL for curve fitting, enter all the data so the run and sign tests have maximum power and the correct number of degrees of freedom are used in the statistics. If you do not have sample variances from replicates, try an appropriate multiple of the measured response (7%?) as a standard deviation estimate. Nothing is saved by using means and standard errors of means. If you do input these then the parameter estimates will be alright, but the resulting statistics will be biased due to using the wrong number of degrees of freedom. This will not matter in a calibration curve.
- If you enter a vector into MAKMAT, do not use the option to rearrange into increasing or decreasing order if you wish to do run or paired t tests which depend on natural ordering.
- With big data sets you could first make small files with MAKFIL or MAKMAT but then join them together using EDITFL or EDITMT. Alternatively use a spreadsheet program such as Excel with the simfit6.xls macro.

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