Step 3. Data processing in GravProtractor

The generated file can be opened with any standard text editor program such as Windows Notepad. The file contains the growth coordinates for each point of the selected polygonal line in x;y pairs separated by a tabulator. Copy the whole content of the file to the clipboard and paste it to the input box of GravProtractor.

8.1.3.1. ‘Calculate’ section

8.1.3.1.1. – Input box

Paste x;y-pairs for growth coordinates separated by a tabulator into the input box.

Alternatively files can be opened via the -button which is located next to the Input box. The box can be quickly cleared by pressing the Clear-button. In the case decimal numbers are used in the input box you can also change the type of decimal separator (e.g. comma or point).

8.1.3.1.2. – Calculate-button

Starts the processing of the input data according to the settings.

Paste coordinates from CB : If this option next to the Calculate-button is checked coordinate data currently stored in the clipboard are directly pasted to the Input-Box 4

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when the Calculate-button is pressed. This option might save some time if many measurements are performed.

!!! Make sure that proper coordinate data are stored in the clipboard when using this option. Otherwise the program might crash.

Copy result to CB : If this option is checked the result from the calculation is directly stored in the clipboard when the Calculation-button is pressed. This option might save some time if many measurements are performed.

!!! This option overrides any currently stored data in the clipboard.

Copy result to ‘Draw’ section : If this option is checked the result from the calculation is directly send to the ‘Draw’ section. Here the former data are replaced and a new gravitropism diagram is drawn.

8.1.3.1.3. – Segments

Defines the number of equal segments in which the root is supposed to be devided.

After changing this value you have to hit the Calculate-button to make the changes visible. If the Calc on change option is checked the calculation is always immediately executed upon changing the segment number. (! Checking this option also overrides the Paste coordinates from CB option.) The range of valid values for the segments is 1 to 65000. Preset is 100.

8.1.3.1.4. – Result Output: Individual Angles

This result box contains for each individual segment the calculated growth angle and the quantized growth angle (in steps of 30°). Below the box you find the result for the mean angle δ which represents the mean value from the individual growth angles.

The Copy CB button can be used to quickly store the angles to the clipboard. These data then can be used for further processing in e.g. Microsoft Excel (see paper).

8.1.3.1.5. – Result Output: Angle categories

This box contains the summed and sorted quantized angles based on the data from box 4. These data can be used for either drawing an individual gravitropism diagram in the ‘Draw’ section or for calculating mean values in e.g. Microsoft Excel. If the latter one is intended the Copy CB button below the box quickly stores the values in the clipboard. If the with Ident option is checked the data are copied together with the respective angle identifier.

170 8.1.3.1.6. – Result Output: Graphical output

This small box shows in black a line drawing of the root to be analysed according to the given growth coordinates. Red colored lines visualize the vectors which are formed by consecutive points on the root path according to the defined number of segments (see above). Vectors for increased numbers of segments usually better match the given root path (compare the right figure for 100 segments with the figure above for three segments).

! The program automatically adjusts the size of the drawing to the box so that the drawing might appear smaller or bigger than the original.

8.1.3.2. ‘Draw’ section

8.1.3.2.1. – Input table.

Here the results for sorted and summed angles obtained from the ‘Calculate’ section can be inserted. This can be achieved by either sending the data directly from the

‘Calculate’ section (see above), by entering values in the individual cells of the table or 5

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by pasting appropriate data that are currently stored in the clipboard. This is done by left-clicking on the ‘Value’ header of the table.

The table can be quickly cleared by clicking the Clear-button.

The option activate error is needed if creation of gravitropism diagrams for plotting mean values with error bars is requested. This opens the additional ±Error-column in the table where values for error bars can be inserted also by direct input or by clicking on the column header to paste data from the clipboard.

Note: Values for error bars have to be calculated separately (e.g. in Microsoft Excel).

Also the values must be positive integers.

8.1.3.2.2. – Draw-button.

The Draw-button provokes drawing of the gravitropism diagram according to the current data in the input table.

8.1.3.2.3. – Pen thickness & Circle size

As the name indicates values for pen thickness and the radius of the diagram circle can be changed here. If the radius of the circle is changed the relative length of the emitted rays is automatically adjusted.

8.1.3.2.4. – Result output: Graphical output

After clicking the Draw-button the gravitropism diagram is plotted in this box. It consists of a circle in the middle of the diagram and emmited rays that represent the relative values of the individual growth directions, meaning that the higher values correspond with the longer rays and with this the favoured growth directions. If the acitvate error option is checked the data from the ‘Value’ column are drawn in black, the respective error bars in red lines according to the values in the ‘Error’ column.

The resulting diagram can be exported by clicking the Copy CB button which stores the image as bitmap in the clipboard. By this way it can be easily exported to programs such as Microsoft Paint or Corel Draw for further image processing.

diagram from diagram

GravProtractor after image processing in Corel Draw

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