WinDisp IP Posting Menu

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WinDisp IP Posting Menu

IP Posting

This option permits the posting of dipole-dipole IP data with each data value selected being displayed in a separate panel. When IP posting is selected the Data Posting Specification menu has the following form:

This menu display contains a number of standard items which are displayed for all menu styles and a number of items which are specific to the particular posting style.

General Posting Options

IP Specific Specifications

With IP posting up to sixteen data values can be selected. These data values are chosen from the available data items by clicking in the grid cell under the column heading Name of Data Variable in the preferred row in the data definition grid. These rows do not need to be defined contiguously, and any valid row will be posted on the display. Clicking in any cell in the Name of Data variable column brings up a drop down box from which the desired data variable can be chosen. The position of the posted data value relative to the data location can be specified by clicking on the cell in the column headed Posting Position and select the required position. A Sample variable can also be selected and displayed.

Depth Variable

With IP plotting, the vertical plotting position is defined using a separate variable to define depth. The variable selected can either be a true depth or an n level value which can be converted to an appropriate depth value by choosing an appropriate depth scale. The Depth Variable is not optional and the Y coordinate variable specified on the File Coordinate menu is ignored.

Depth Scale

Once the Depth Variable has been selected, the actual plotting position can be modified using the Depth Scale parameter. This value may be positive or negative but should not be zero.When gridding IP data, the vertical axis of the image generated is multiplied by the depth scale, so it is recommended that these values be selected to obtain a reasonable height for the image before the data is gridded. If the depth scale is changed after gridding, the image file will not be displayed correctly.

Dipole Length

With IP plotting, the plotting position depends on the dipole length used in collecting the data. The value in this text box should be set at the dipole length for the survey.

Panel Separation

When multiple IP panels are to be posted there needs to be space left between each of the panels. This separation distance is set to 2cm by default, but may be changed to any positive value to achieve a better presentation.

Display Data Range button

Once the coordinates and required data variables have been defined, the user can check the range of data values contained in the file by clicking on the Display Data Range button. Clicking on this button brings up the Data Range Menu. When this button is clicked for the first time, the currently selected data variables are read from the file and stored in a temporary binary file to speed future access to the data. This temporary file will be retained for the current WinDisp session or until it becomes invalid through a change to the data variables chosen or the line variable, so it is recommended that all data of interest are selected on first entering the Data Specification menu.

Define Data Variable

After specifying the coordinates and required data variables and the area limits and map scale, the parameters determining how the individual data values will be posted need to be specified. This is achieved by clicking on the Define Data Variable button. This will bring up the parameters for the currently selected line in the data definition grid, or the first variable specified in the grid if there is no currently valid selection. Clicking on the Define Data Variable button brings up the following form:

Data Variable

This displays the user name of the currently selected data variable.

X Offset

This value specifies the distance in mm by which the data text is to be shifted horizontally from the specified posting position selected in the data definition grid. A positive value will shift the label to the right and a negative value will shift the label to the right.

Y Offset

This value specifies the distance in mm by which the data text is to be shifted vertically from the specified posting position selected in the data definition grid. A positive value will shift the label up and a negative value will shift the label down.

Label Size

This value represents the size of the label in cm used to display the selected data value. If the size is set to zero the label will not be displayed.

Null Value

This text box displays the null data value for the current data variable, this value is provided for information only and the null data value should be changed on the Specify Data Names menu

Logarithmic Scaling

This check box specifies if the log (base 10) of the data value should be used in posting the data.

Number of Decimals

This integer value specifies the number of digits after the decimal point to be used in displaying numeric data values in text format.

Label Rotation

This value specifies the rotation to be applied to the currently selected data variable and is measured in degrees positive counter clockwise about the centre of the label position. This rotation is applied after any posting rotation specified on the main Posting Specification menu.

Text Colour

This box displays the text colour which will be used to display the selected data value. If the colour needs to be changed, click on the colour box to bring up the Pen Colour Specification Menu.

Image File Specifications

When displaying an IP data value in a panel, a grid file may be optionally displayed as a background for the posted data. To do this an image file needs to be selected and the image presentation style needs to be defined.

Display Image Checkbox

This check box is provided to allow individual images to be turned on or off. The image will not be displayed if the check box is turned off. If the check box is turned on and the Display Image menu item in the Display List is also turned on then the image will be displayed.

Image File Name

This is the name of the grid file to display. The file name may be edited directly in the text box, or a File Location dialogue box can be brought up by double clicking on the file name text box. If the grid files are generated by accessing the gridding options using the Display Data Range button, the file name and formats for each data variable will be automatically supplied.

File Format

This text box displays the format of the specified Image File. This format does not usually need to be specified as WinDisp automatically determines the file format.

Image Style

This drop-down box allows the user to specify the image display style. All options for image files are available, however due to limitations with the colour palette if different styles are selected in different panels, the displayed image will only be correct while it is being displayed.

Colour Lookup Table

This text box contains the name of an optional colour lookup table to be used for displaying the image. When multiple panels are being displayed, this facility allows the user to use a single colour lookup table for all panels so that a particular colour will represent the same data value in all panels using the same lookup table.

Invert Colours

Selecting this check box has the effect of reversing the order of colours in the current colour palette. For the standard colour palette this results in low values being displayed as red and high values being displayed as blue.

Histogram Equalise

Selecting this check box has the same effect as the equivalent check box in the Image Specification menu.

Contour File Specifications

When displaying an IP data value in a panel, a contour file may be optionally displayed as a background for the posted data. To do this an contour file needs to be selected and the contour specification parameters need to be defined.

Display Contours Checkbox

This check box is provided to allow individual contour displays to be turned on or off. The contours will not be displayed if the check box is turned off. If the check box is turned on and the Display Contours menu item in the Display List is also turned on then the contours will be displayed.

Contour File Name

This is the name of the contour file to display. The file name may be edited directly in the text box, or a File Location dialogue box can be brought up by double clicking on the file name text box. If the contour file has been generated by using the Generate Contours button, the file name will be automatically supplied.

Contour List Name

This text box contains the name of the contour list file to be used for displaying the contours and this file must be supplied for each specified contour file. This file can be generated from the Write Contour List menu item on the Contour Specification menu or can be written out when the contours are generated.

Edit Contour List

If there is no available contour list or if the current list needs to be modified, clicking on this button brings up the Contour Specification menu. From there the contour specifications can be modified and the modified list written to a contour list file.

Generate Contours

Once an image file has been selected, the image file may be contoured by clicking on this button. This brings up the Generate Contours menu from which the contour ranges can be defined and the contour file generated.

Selected Data Variable Drop-down Box

At the bottom left hand corner of this form is a drop-down box containing a list of all data variables currently specified in the data definition grid. By selecting each of the data variables in this list, the parameters defining the posting of each data variable may be specified without returning to the main form.

Finally the Display Data Range menu is accessible from this menu by clicking on the Display Data Range button at the bottom of the screen.

Any changes made from the menu can be discarded by clicking on the Cancel button, otherwise the changes will be saved if the OK button is clicked.