More info about MacDiff 4

(These page are also available in German language)

About 50% new or changed code since version 3.3.1. The program size increases to 1.4 MB (200 Kbyte more). The RAM requirement is 3.6 MB (with virtual memory) or 4.6 MB (without v.m.) - about 1 MB more.

Please inform me about bugs or suggestions to improve the software.

System 7.x User: You need the init "Appearence Extention" and the control panel "Appearance CDEV". Please download here.

68K user: Unfortunately, because of serveral compiler and performance problems, there is no plan to develope a MacDiff 4.0 for 68K. The old version 3.3.1 of MacDiff is the last 68K version, which remains available to download. Please let me here if you need the advantages of MacDiff 4.0 on 68K Macs.

The changes:

- MacDiff 4 works with intensities up to 1,000,000 counts (no longer 32768-count-limit!).
- holds source file names and formats. Goto the Info window to read.
- holds history info of all modifications to see what's happened with your data. Goto the Info window and click on "Get History"
- holds comments to each profile as written by the user. Goto the Info window and click on "Get Comment"
- holds counting times (also displayed in diagrams, if there are other than 1), if the source file format stores counting times.
- reads and writes the old MacDiff 2/3 data format (write via Export).
Goto the "Undo..." Menu (cmd-z) of the "Edit" menu
Fit a single peak or a group of (up to seven) peaks - possible profile functions are Gauss, Lorentz (normal, intermed, modified), Pearson VII, and Pseudo Voigt. Least square refinement. Asymnetric (splitted) or symmetric function. Some settings in a new "Peak Fit Settings" dialog.
 
 
Single Peak Fit: Goto the Preference menu and enable the "Fitting Profile Function" check box. Alternatively you can type "f" key on your keyboard during click on a peak. Goto the "Peak Fit Settings" dialog to choose the function of your choise, asymmetry or symmetry, how many refinement loops you want and set the refinement accuracy (least residuum reduction, in older betas: variation). Furthermore, you can lock peak limits and choose a faster calculation mode. Zoom your diffractogram that your peak fills the window (alternatively, enable "Zoom Peak Area" icon or menu). Then double click the peak. After a calculation time (depends from your settings and from your Mac) MacDiff draws the function directly into your diffractogram. It disappears after next click on "Done". The profile fit data are showing in the same way instead of the normal peak data on right hand top as used for standard peak calculations. The complete function parameter are showing in the "Peak info" window, goto the "Fit data" card. Also the report list contains the peak data coming from function (d value, intensity, area, FWHM). Note: All the data coming from fitted function are displayed in blue color!
 
Multipeak Fit: Eventually, goto "Peak Fit Settings" to set your fit preferences. Zoom your diffractogram that all your peaks to measure fill the window. Hold down the "Shift" key and click on all peaks of your choise. The cursor will display the peak number 1 to 7. Release the "Shift" key. Then click on the "Fit now" button. Wait and look to the display how the refinement works (residuum must going smaller). If ready, MacDiff draws all the profile functions together with the envelope and the residuum curve (both can be set as invisible in "Peak Fit Settings) directly into your diffractogram. The peak display on top of right hand display the data of the last peak. If you want to see the data of the others, click on the number fields on the bottom of the display frame. If you want to continue the fit for more refinement, you fit only with parameters of your choice by locking the other in the "Peak Fit Settings" dialog. All the d-values, intensities, areas and FWHMs coming from functions are stored in the report. If you want to see all stored data, look into the Report window ("Show Report") or, if you want to see the complete data set, goto the in the "Peak Info" window.
 
If holding ALT key, you only need a single click to analyse a peak.
MacDiff now stores counts as floatings (that means: with a decimal point). Many calculations of your count data (Smoothing, Alpha-2 Stripping, Divergence, Base line calculation ...) produces non-rounded floating data now. This resulted in more exact data and more accurate display, which has no longer jaggies (especially of your counts are smaller than a few 100). If you want no longer displaying decimal data, goto the Preference window ("Miscellaneous Prefs") and enable "Display/Save data as integers". If so, your Report table will saved with rounded data too. Internal, MacDiff 4 allways use floatings.
In peak search and peak limit calculation MacDiff uses internal smoothed counts. Thus, the number of mistakes in choosing smaller peaks ("ghost peaks") are diminished drastically, especially if non-smoothed diagrams are measured.
In sessions you can now separate, smooth the base, and reduce noise of a set of diagrams.
The new prefs file is "MacDiff Prefs 4", found in the preference folder of your MacOS System folder. The old MacDiff 3 preferences will be unconsidered. You should change your settings to an environment of your choice after first start of MacDiff 4 .
You can edit the Alpha-1/Alpha-2 ratio, and the wavelengths of Alpha-1 and Alpha-2.
You can collect PDF (Powder Diffraction File) data of your choise into the peak database of MacDiff. Goto the PDF database retrieval software and write all your collected cards in a file of the NBS*AIDS83 format. Then goto MacDiffs peak database window, create a new database or choose an existing one. Then click on "Import". A dialog appears, having several options to filter PDF data sets (read all data, read only the hkl with a minimum intensity, read only hkls in a d-interval, read only a number of highest hkls.). Then click on "Import" and choose the file coming from PDF. You should update all the records after importing before using in MacDiffs "Peak identify" routine (in some cases, you must restart MacDiff before it works fine).
Choose a record in the peak database. Click on "Generate". A dialog appears, having some settings need to calculate an artifical diffractogram from your peak data (profile function, maximum counts, angle steps, anode type, a.o.). Then click on "Generate". MacDiff calculates a new diffractogram with the peaks of the record.
Some bugs are removed. Furthermore, there are long file name display support, scroll by keys, shift-click for choosing multiple file sessions. Multiple files as earlier determined are no longer automatically removed by opening the multiple plot dialog.
Self updating peak identify, report and peak Info listings, presented on new smaller windows, are redesigned to remain constantly opened - they will automatically updated in the background, if nessessary. You need no longer close these windows during work with diffractograms.
 
Now you can store up to 200 lines. You can navigate by cursor keys.
- a peak search method (click on the icon down of "mode"),
- profile fitting of a peak set by choosing a same number down of "Fit-No"
- calculation of relative percentages of intensities or areas of a set of peaks (click on the check box down of "Rel%") - if you need a factor here (like BISCAYE-factors), type in the field "Factor" -
- a formula generator: Type in a free formula of your choice to calculate data which are not stored in MacDiff (look into "Syntax..." for more info).
The "Calculate Profile" dialog is redesigned. Type a formula of your choise. Read "About Syntax..." for more info. Because of interpreting the formula, the calculation are very time-consuming.
It is splitted into 3 parts, called by a pop-up menu. Some new features added.
 
IMPORTANT for FWHM measurements!
 
- "Adjust FWMH to base line": FWHMs can be measured/displayed as adjusted to the base line - If the base line of the peak decreases or increases, the FWHM shows the same course as default (obligate for peak fits). If you want exactly horizontal FWHMs in ever case (like in earlier versions of MacDiff), disable the check box.
There is a second menu comand in apple menu "Launch Manual...". One of the english or german manual must be placed in the MacDiffs folder to enable this menu.
 
The database now comes in a "Complete set" of 532 minerals with more than 22.000 peaks. Furthermore, there are sub-databases of Sedimentary rocks, Magmatic rocks, Metamorphic rocks, Ore Minerals, and Clays.
 

Minor changes:

Bugs fixed:

 

Rainer Petschick, Aug. 31, 1998