DbPlot

DbPlot: an application to plot any time-serie stored in the database in ASCII

Overview

This Visual Basic 6 program will query the EMEWS database to retrieve time-series and plot them on the screen. It can refresh the plot by periodically requerying the database at a specified interval. Zoom and export functions are available. It can also open .PED (ProEssential Data) files such as the ones created by the web dataplotter application. The database is accessed via an ODBC interface. It has been successfully tested with Access and Sybase databases.

Installation

  1. Unzip DbPlot.zip and run setup.
  2. If not done already install the ODBC driver of the database before running the application. For more information see the Access or Sybase section.

Operation

  • Run DbPlot by clicking Start, Programs, EMEWS Select one type of channel, a list of stations and channel number should appear on the right, select at least one or more (holding the CTRL key) channel. Up to 6 type of channels and an unlimited number of channel can be displayed simultaneously. If you enter a refresh interval, the database will be requeried and the plot updated, this is used for continuous monitoring.
  • click OK, the plot should appear, the waiting time depends of the amount of data requested
  • To zoom, hold the SHIFT key down and select an area with the mouse, an horizontal scrolling bar will be available to move the zooming area, to unzoom press ‘z’
  • Export and other functions are available by right-clicking the plot area
  • A web application, dataplotter, installed on some servers generates a file called pesgo1.ped. This file can be opened in DbPlot for further analysis or exporting. To do so you need to associate the DbPlot.exe application with PED files. Open one of the dataplotter web application with your browser and click on the file PESGO1.PED, you will be prompted to download or open, choose open. This will download the file in a temporary directory. After completion you will be prompted to select an application, select the program DbPlot.exe which is located in the install directory selected at installation (leave the box « always use …  » checked).
    The plot should appear now, right-click on the plot to display the option menu.
    If you repeat the procedure you will not be prompted for an application since Windows remember that PED files are associated with DbPlot. Your browser also offers the possibility to open the .ped file without prompting you to download or open each time, to do so remove the check in the box « always prompt before opening ».

Technical information

you might receive a message stating that DCOM95 is needed, you can dowload it from:
http://www.microsoft.com/com/dcom/dcom95/download.asp

you might receive an error message if ADO is missing, it can be downloaded from:
http://www.microsoft.com/data/download2.htm
choose « Microsoft Data Access Components 2.0 SP2 Redistribution Typical Setup » (6 MB)


The application uses the ProEssential Scientic Graph object (ActiveX) Version 2 from http://www.gigasoft.com/

documentation for ActiveX Data Objects (ADO) is at:
http://www.microsoft.com/data/ado/adords15/

if you are interested about redistributing ADO you can read this article
http://support.microsoft.com/support/kb/articles/q185/6/22.asp

Sources files are available, any improvement is welcome but should be sent back for inclusion in the EMEWS user guide: DbPlot.vbp, form1.frm, param.frm