FAQs and bug repairs

Bug repaired in Viewxsxn version 1.2a:
Version 1.2 occasionally dropped the minimum x coordinate resulting in a program crash when attempting to make a cross section. Also, NaN (not a number) appeared for the minimum x in the header of Arcview (*.asc) and Surfer files (*.grd).

FAQs (frequently asked questions)

#1 When I “open new set of gridfiles”, I get the menu "tops to graph" and it asks for a value. I don't know what value to enter here?

#2 Can Viewxsxn support Surfer 7 files? (After uploading files, why might the program shut down with the message “diasxnio.exe has encountered a problem and needs to close”)

#3 When I click “View”, it gives me the following error:
"Run-time error '429':
ActiveX component can't create object"

#4 Can you plot the cross sections in other software besides GRAPHER?

#5 Will I get cross section data files if I don’t have Grapher installed when running Viewxsxn?

#6 After assigning layer numbers according to the stratigraphy and then running the program (calculate layers with current settings), the program seems to freeze. When I click anywhere on the window, it shows "Not Responding".

#7 Is it normal for the DOS window to disappear for a second, when I click the "Calculate layers using current setting"

#1 QUESTION: When I “open new set of gridfiles”, I get the menu "tops to graph" and it asks for a value. I don't know what value to enter here?

REPLY: Enter the number of already-existing grid files (one for each top) that you plan to open to construct your cross section. If you want to generate surfaces, use the “generate new set of grid files” button.

#2 QUESTION Can Viewxsxn support Surfer 7 files?
[originally posed question: When I enter the number of layers to graph, it uploads the files o.k., however, when I press any button after that, the program either freezes the computer or shuts down with the message "diasxnio.exe has encountered a problem and needs to close. We are sorry for the inconvenience". I don't know if there is something wrong with the original file or I am making a mistake in the input values.]

REPLY: No, but it does support Surfer 6 (binary) and Surfer ASCII formats.
[original reply: I read your grid into my program, and though it read in o.k., the x,y and i,j coordinates were meaningless. Looking at the header of the grid file, I see that it is a Surfer 7 grid. At this point, my program cannot read Surfer 7 grids (they tag a lot of information about boundary lines and faults etc. which I don't use, and hence have not learned the "new" grid format). I do support ASCII grid and Surfer 6 (binary) grids. If you export (SaveAs) from Surfer into any of these earlier formats, the program should read it fine, or send it to me and I'll try to read it.]

#3 QUESTION: When I click “View”, it gives me the following error:

"Run-time error '429':
ActiveX component can't create object"

REPLY: The ActiveX error occurs if you don't have (or the program can't find) your Grapher program installed.

#4 QUESTION: Can you plot the cross sections in other software besides GRAPHER?
[originally posed question: I understand that the x-section can only be viewed in Grapher. Does Viewxsxn create a grapher file? Or is there another method by which the x-sec can be viewed?]

REPLY: You can plot the graph in other software besides GRAPHER using the data files that are generated. One data file for each layer is produced and stored in your Viewxsxn program directory (usually Program File\Viewxsxn). For example, layer #1 has data file layer1plt1, a Grapher data file. These files are straight ASCII and only have x,y coordinates row by row with no header information, and are thus importable into any graphing program (like Excel for example). If you go this route you will have to remember what coordinates (cell addresses) you start and end your plot on. My invocation of Grapher tracks this for you, but not in the data file. For example, an "x" coordinate may range from 0 at (1,1) to 5.88 at (NROW, NCOL), but those two cell addresses are not in the x-y data file. The “x” coordinate of the cross section plot is determined from your input (e.g. Surfer) grid spacing and the startpoint and endpoint coordinates you specify for the plot, with x=0 on the left side of the plot.

If you plot more than one surface on a graph, or plot a number of different graphs (one for each time you press the view button), you will have to retrieve all the datafiles. For example, for a 3 layer graph, plotted twice, you would have:

layer1plt1.dat
layer2plt1.dat
layer3plt1.dat

for plot 1, and

layer1plt2.dat
layer2plt2.dat
layer3plt2.dat

for plot 2. Careful. These files are overwritten with each new session (i.e. start up) of the Viewxsxn program.

#5 QUESTION: Will I get cross section data files if I don’t have Grapher installed when running Viewxsxn?

REPLY: Yes, but then the program will get the ActiveX error and quit, so you will only be able to do this one plot at a time (restarting the program for each desired plot). Without Grapher installed, the program does call and return from the graphing subroutine before Grapher is invoked, so it should produce the x-y data files. There may be system dependencies however. When an application is forced to quit, it is always questionable whether, and how much of, an output file is produced on disk.

#6 QUESTION: After assigning layer numbers according to the stratigraphy and then running the program (calculate layers with current settings), the program seems to freeze (when I click anywhere on the window, it shows "Not Responding").

REPLY: YOU MAY NOT BE DOING ANYTHING WRONG. Are you using “projection” to complete your cross section? If so, suggestion 1 is to try making a fold, even a fold with a very small amplitude and very large wavelength. It seems counter-intuitive, but in my program, a projection takes much longer to calculate than a fold. The reason is that with fold, the entire grid is calculated in one sweep. With projection, and for each layer, every node must search the whole array for the nearest contact to calculate the projection depth. As a result, you get a NCOL x NROW sweeps of an NCOL x NROW matrix for each NLAY layer, and it takes a lot of time if the grid gets large. Suggestion 2 is to run it overnight. The system may say "program not responding", but all processing programs in Windows do that if they are running and not doing any I/O for awhile.

As for the slow “projection” processing, I plan to improve this in future releases. I've got some ideas to shorten the processing time (like storing just the contact nodes in an array so that just the appropriate contact is searched and not the whole array). This should significantly improve the time.

#7 QUESTION: Is it normal for the DOS window to disappear for a second, when I click the "Calculate layers using current setting" OR does the DOS window stays for the entire process?

REPLY: The VB is actually driving 2 DOS-fortran processes (one at a time) and will from time to time switch between them by closing one and starting the other. Diasxnio is launched (or relaunched) after responding to the last queue for a blanking file (for the last layer read) when using the Open Files button. Geofold is launched (or relaunched) after selecting "Open" on the openfile form for reading the DEM (part of the "Open Geologic Map and Elevation Files" button on the Fold and Projection parameters form).