Calculations

Once you define all the calculation input parameters, you will be able to run efficiency calculations. To define these parameters you need to:

  • Select an appropriate detector, container and geometry from the lists
  • Define the radioactive source height and material (also its width, if it is different than the container inner radius)
  • Choose the set of energies of interest for calculation
  • Select the reference efficiency curve, if you want to calculate efficiencies (otherwise, only effective solid angles will be calculated)
  • Choose the calculation precision.

With all these parameters set, you are ready to run calculations, or to save these calculation parameters and run them some other time, or even on some other computer.

To perform calculations from the currently selected parameters, simply click the button “From current parameters” on the “Calculations” ribbon tab.

Before calculation starts, Angle checks all input values for possible incompatibilities. If there are one or more incompatibilities in the input parameters, such as the container not compatible with the detector (for example, if you try to use a well detector with a Marinelli container), you will get the error message and the calculations will not be performed.

If all input parameters are correct, Angle will ask for the name of the file where the output results will be saved and the calculations begins. While calculating, Angle displays information about the calculation, as shown in the next figure.

The first label shows the source of the input parameters – the name of the parameter file or “Selected calculation parameters” in cases when running calculations from current parameters (more about the parameter files is in “Saving input parameters”). The second label shows the name of the output file. A progress bar in the central part of the calculations dialog box displays the completion progress. Finally, the elapsed calculation time and the estimated time are displayed below the progress bar.

Calculations can be canceled anytime by clicking the “Cancel” button

If you check the option “Turn off the computer when done”, the computer will be shut down automatically when calculations finishes. This is useful for time consuming calculations (e.g. long batch jobs), where computers are left unattended to finish calculations. Once all calculations are finished, the shut down dialog will be displayed:

The shut down dialog will start a 30-second countdown, after which the shut down procedure will be initiated. During this period it is possible to cancel the shut down, or even force it before the timer reaches zero.

On Windows Vista and newer operating systems, Angle can display the calculation progress on the Windows Taskbar. This is useful in case of lengthy calculations (e.g. running many calculations at once), so you can monitor the progress of calculations while working in other applications, even if the Angle window is not visible. To see how to enable or disable this functionality, see the section Configuration.

Calculation results

After the calculations are finished, a window with the calculation results will be displayed automatically.

Calculation results are shown in a table: values of the effective solid angle (Ωeff) and efficiency (εp) are shown for each energy from within the given energy set.

The εp values will be calculated only if the reference efficiency curve is defined. Otherwise, only Ωeff values are calculated.

The calculation results window also contains all the input parameters used for calculation: detector, container, reference efficiency curve, etc. To see the details for each of them, simply click on the name of the parameter, or the “info” button on the right-hand side of it.

The input parameters containing detailed information can be recognized by the “info” button at the right-hand side. Also, the cursor changes its shape to a pointed hand when moving over these parameters.

The scaled preview of the whole counting arrangement is displayed in the right-hand part of the calculation result window. As with other previews, you can also zoom-in and zoom-out of the preview image, pan it and export it to various raster and vector graphics formats (read more in the Data entry section).

Calculation results can be copied to the clipboard by clicking the “Copy to Clipboard” button and pasted to other programs, for example to spreadsheet or word processing software.

Calculation results can be opened and reviewed anytime later by re-opening the calculation result files. To do this, choose the “View calculation results” option from the “Calculation” ribbon tab and selecte the calculation results files to display.

It is possible to select more than one calculation results file:

To select multiple files use any of the following standard Windows procedures (or their combination):

  • By clicking a file name while holding the keyboard Ctrl key you can select/deselect one or more files.
  • By clicking one file name and then clicking on another file name while holding down the Shift key, all files between those two will be selected.

By pressing the Ctrl+A key combination you can select all files in the folder.

If you select more than one file to display, the calculation results window will contain a list of files in the left-hand part of the window. By clicking a name of a file, the results from that file will be displayed in the right-hand part of the window. This option is useful when comparing the results of calculations or when transferring the results to another application.

To copy the results from all files at once, click the button “Copy all results to Clipboard”, located under the list of files.

Calculation reports

To print calculation results simply click the “Print calculation results” button. The resulting one-page document will contain the results, together with the summary of the input parameter data, counting arrangement schematics, and calculated efficiency curve (if efficiencies were calculated).

If you want to print a detailed report, you can do it by clicking on the “Print calculation report” button. The report will contain the results, as well as all the input parameter data used in calculations – thus making the results traceable to the input values.

Calculated efficiency curve

Angle 4 introduces another new feature – now you can see and export the graph of the calculated efficiency curve. To see it, click on the “View efficiency curve” button, located just below the preview image in the calculation results window. The efficiency curve graph window is shown in the next figure.

The graph shows both the calculated efficiencies for selected energies (red square markers) and the fitted efficiency curve (solid blue line). The reference efficiency curve is shown as well (dashed blue line). Angle uses the same intervals and polynomial orders for both curves.

To be able to calculate efficiencies, Angle needs you to specify the reference efficiency curve.

As with other previews, you can also zoom-in and zoom-out the preview image, pan it and export it to various raster and vector graphics formats (read more in Data entry section).

Exporting to ORTEC GammaVision

The calculation results can be exported to ORTEC GammaVission format, simply by clicking on “Export to ORTEC GammaVision” button.

Export to ORTEC GammaVision will be possible only when efficiencies have been calculated, i.e. when a reference efficiency curve is defined. Otherwise, the “Export to ORTEC GammaVision” button will be disabled.

Exporting to Canberra CAM files

Calculation results can also be exported to the Canberra CAM file format, simply by clicking on “Export to Canberra CAM file” button.

Export to Canberra CAM file will be possible only when efficiencies have been calculated, i.e. when a reference efficiency curve is defined. Otherwise, the “Export to Canberra CAM file” button will be disabled.

Canberra software must be installed on your computer in order to be able to export CAM files from Angle.

Saving input parameters

All calculation parameters can be saved to a file and be used for further calculations later. This is convenient, for instance:

  • When calculations will not be performed immediately.
  • For preparing calculations which will be performed on another computer.
  • For preparing the inputs for multiple calculations at the same time (batch jobs).

To save calculation parameters to a file, select all calculation parameters in the same way as when running calculations and click the button “Save calculation parameters” from the ribbon tab “File”, or by pressing the Ctrl+S key combination on the keyboard.

Before saving, Angle checks all input values for possible incompatibilities. If there is an incompatibility in the input parameters, such as an invalid detector-container combination (for example when using a well detector with a Marinelli container), the error message will be shown and file will not be saved.

Running calculations from saved parameter files

To perform calculations from one or more saved parameter files, click on “From saved calculation parameters” from the “Calculations” ribbon tab.

After choosing one or more previously saved calculation parameters files, the calculation begins. The output files will have the same name as the input files (except for the extension, which will be “.outx”).

If you selected more than one file for calculations, the dialog box displaying calculation progress will additionally contain the information about the overall progress, the number of files being processed and the elapsed time for the overall process.

Output files will have the same names as the input ones. If output files with the same names exist they will be overwritten without warning.

After the calculations are finished, the output results will be automatically displayed for all selected files, except in cases when an automatic computer shut down is requested.