ردازش داده های ژئوشیمیایی در محیط MapInfo(GIS) با تهیه یک برنامه کاربردی و تلفیق آن با Statistica, Surfer
|دسته||دورسنجی و GIS|
|گروه||سازمان زمین شناسی و اکتشافات معدنی کشور|
|مکان برگزاری||بیست و یکمین گردهمائی علوم زمین|
|نویسنده||محمد رضا حسین نژاد فریدون قدیمی عروس محله رضا احمدی|
|تاريخ برگزاری||۲۹ آبان ۱۳۸۴|
پیچیدگى و حجم زیاد داده هاى ژئوشیمیایى و نیاز به پردازش داده ها امکان استفاده از یک نرم افزار سیستم اطلاعات جغرافیایى و یا آمارى براى پاسخ گویى به همه نیازها را دشوار ویا حتى غیر ممکن ساخته است.
یکى از راه حلهاى اساسى براى تخصصى کردن یک نرم افزار نوشتن یک سرى برنامه هاى تخصصى در محیط همان نرم افزار است. راه حل دیگر و پذیرفته شده توسط بسیارى از کاربران برقرارى ارتباط بین چند سرى از نرم افزارهاى مورد نیاز مى باشد.
در این مقاله سعى شده است با نوشتن یک برنامه به زبان MapBasic که زبان برنامه نویسى نرم افزار MapInfo(GIS) میباشد و همچنین با استفاده از تکنیک DDE (Data Dynamic Exchange) بین یک سرى از برنامه هاى مورد نیاز پژوهشگران علوم زمین مثل Surfer, Statistica و MapInfo این ارتباط را برقرارکنیم تا کاربران بتوانند براحتى در تحقیقاتشان از آنها استفاده کنند.
A Geochemical Data Processor Integrating MapInfo, Surfer, Statistica and Geoche MapBasic program
The complexity and diversity of data and data processing now being used in geochemical data analysis are increasing at such a pace that it is difficult to maintain a single software package capable of performing all required tasks. A typical solution is to use a number of commercial software packages loosely linked via file format conversation routines or other customized communication paths. Creating and maintaining these paths are possible by using a MapBasic program with DDE technique for communication between this commercial software. We attempted to create a friendly interface for geochemical data processing by using some necessary package requirements in geosciences and also integrated computer systems for implementing various spatial analyses and modeling which can serve as synthetic tools for geochemical exploration. Demonstration will be made by using MapInfo and MapBasic, incorporation with Statistica and Surfer.
The commercial components
The commercial components used here are three widespread standard programs: griding and contouring software SURFER 5.0(by Golden Software, 1994), MapInfo professional 4.0 a GIS software (by MapInfo Corporation 1995) and for data analyzing and statistics, STUTISTICA for windows (by StatSoft, Inc. 1995).
SURFER is a flexible contouring and 3-d modeling package. Its principal functions are distributed in griding (GRID), contouring (Contour), 3-D modeling surface, viewing (VIEW), and output (Map) modules. All modules read and write ASCII files in addition to the internal binary format, providing easy data exchange with principal programs. Surfer is a contouring and 3D surface plotting program that runs under Microsoft Windows and therefore quickly and easily converts our data into contour map and surface plots. And with all the options available, we can customize the maps to produce exactly the presentation we want. Even though Surfer does a good job, it does not have any facilities to import MIF/MapInfo files.
MapInfo probably is one of the best GIS systems on the PC basis; because of its architecture and programmability it may be customized for many task. MapInfo is developing and delivering technology that spans the enterprise. MapInfo offers the best combination of software, applications and services data visualization. But unfortunately MapInfo does not have an elegant way of handling contour map and special data processing methods such as Kriging, Moving Average, Trend surfaces and etc.which are required in geosciences, but it can imports DXF files, and SURFER is capable of writhing DXF files.
STATISTICA is a developing package for statistics, data analysis and data management. It has some facilities to import, export, read and write ASCII files and provides easy data exchange with principal programs. In addition to file import/export facilities, STATISTICA supports multiple Clipboard formats, OLE client and server functions, and DDE/API capabilities in order to exchange data and/or graphs with other applications.
There are some reasons to select these commercial software for integration:
a) They are three widespread standard programs with different capability and necessary in geosciences
b) They do a good job for the price
c) High exploit in geological sciences
The Map Basic component
GEOCHE is a Map Basic program that we have written for data pre-processing, and some special command such as Grid, Sample Location, Graph map, XYZ diagram, Picture show, Cut layer, Intersection, Send to Excel, Send to Statistics, and so on. This program also can produce maps with customized title block, scale bar and legend on map (Figure 2). Here we have a brief introduction for some command:
By using Grid function, it allows to grid data with one of the common method such as Inverse Distance to a Power, Kriging, Minimum Curvature, Polynomial Regression, Radial Basis Function, Shepard's Method and Triangulation W/Liner Interpolation, it also makes grid net for sample location or latitude/longitude, and/or other grids on map. The result gives a new table of estimated values for each variable, then will import into MapInfo to form additional grid layers of the same database ,see figure 4
The interrelationships of data properties and their spatial characteristics may be rapidly evaluated by graph map, MapBasic program. By select anomalous points on the graph we can see where they occur on the map, similarly by the select object on a map we can see where they occur on the graph. The flexibility of the method encourages and open, intuitive, and innovative exploration data.
This program also able to perform some of favorite mapping functions to a graph. Clearly, the primary reasons for creating this tool are to discover different ways to make better use of data in MapInfo (or other data products). It allows a deeper understanding of the data without a deeper understanding of the software - this is an important point in differentiating between tools and applications for data analysis.
The form in which data can be exported to external software varies from one system to another. In a raster formats, data can be exported as a stack or raster images, each raster having the same number of rows and columns. On the other hand, in the vector formats, a polygon overlay can be used to create map formed by the intersection of all maps that are to be combined. On such a map, each polygon is a unique special object, and is linked by a keyfield to a record in an attribute table. This type of unique polygon table can be extended for multiple maps. Alternatively, if geometric attributes of individual polygons are not needed for modeling, a unique conditions map, and associated table, can be generated. Polygons having the same vector of attributes are combined into unique condition classes. In case, the unique conditions, or the unique polygons, table can export, preferably in an ASCII format, ready to be processed by external software. New attribute tables are generated with the modeling results, containing the unique polygon number or unique condition class as a keyfield, ready to be re-imported into the GIS for display, and further analysis.
First we attempted to create a friendly interface for our goal by using Visual Basic language (Figure 1). This interface has five main components that make up two groups. The first group includes MapInfo, Statistics and Surfer, the function of each component being to run the specified software and the second group includes Geoche and Communicate. Geoche is a MapBasic program and has some data processing command required in geosciences (Figure 2), and launches the Visual Basic application. This MapBasic program can also import and export tables easily and automatically to the Statistica, Surfer and Excel.
Communicate DDE command is a visual basic application that acts as a DDE (Dynamic Data Exchange) client, with MapInfo, Statistics and Surfer as the DDE server. A DDE conversation is a process that can take place between two windows applications. Both applications must be running, and both must support DDE conversations. An application such as MapInfo can be involved in multiple conversation simultaneously. In a conversation, one application is active; it begins the conversation. The application is called client. The other, passive application is called server. The client application takes all initiative; for instance, it sends instructions and queries to the server application. The server reacts to the instruction of the client. We could use MapBasic’s RUN PROGRAM statement to launch this Visual Basic application that displays a custom dialog; the Visual Basic application that manages the dialog could then initiate a DDE conversation with MapInfo in order to communicate our dialog choices (Figure 3).
Geochemical exploration software that we designed established on GIS platform (mapinfo) has strong function, friendly interface in geochemical field analysis and can play a positive role in the geochemical exploration
Some of them are based on having available several interlinked ways of looking at the data, including the context. Thus the interrelationships of data properties and their spatial characteristics may be rapidly evaluated. The flexibility of the method encourages and open, intuitive, and innovative exploration data.