DDEIMPORT procedure

Get data from a Dynamic Data Exchange (DDE) server, PC Windows only (D.B. Baird).


Options

PRINT = string
Controls whether a catalogue of the structures read from the DDE server is printed (catalogue); default cata

SHOW = string
Whether to display the spreadsheet within the windows interface (no, yes); default no

IMETHOD = string
How identifiers are specified for the columns (read, supply, none); default read if COLUMNS is unset, supply otherwise


Parameters

SERVER = text
Name of DDE Server (ignored if GDEFILE is set); default Excel

TOPIC = text
Name of DDE Topic

ITEM = text
Name of DDE Item

GDEFILE = text
Name of a previously saved GenStat DDE link file

COLUMNS = text
Names and/or type codes for the columns read (the type of column can be forced by ending the column name, if supplied, with the code ! for a variate, # for a variate, and $ for a text)

ISAVE = pointer
Name of a pointer to save the column identifiers


Description

A DDE server is another windows program (e.g. Microsoft Excel) that will supply data on a DDE request. The data to be read via DDE is specified by the DDE triplet: server, topic and item. Alternatively the name of an existing GDE file containing these can be specified using the GDEFILE parameter. GDE files can be created by opening a spreadsheet with the Spread > New > from DDE Link menu item, and then saving the resulting spreadsheet with the file type GenStat DDE Link (*.GDE).

   The TOPIC for Excel has the format '[<FileName>]<SheetName>' e.g. '[D:/Work/Data.XLS]Data Summary', and the ITEM has the numerical format R<n1>C<n2>:R<n3>C<n4> e.g. 'R2C3:R25C5' or the format '<Column letter><rowno>:<Column letter><rowno>' e.g. 'C2:E25'.

   The TOPIC for QPW has the format 'FileName' e.g. 'D:/Work/Data.WB3', and the ITEM has the format of 'Sheet:<Column letter><rowno>..<Column letter><rowno>' e.g. 'B:C2..E25'.

   The COLUMNS parameter can be used to set the names of the structures. It can also be used to force the type of column by ending the column name with the code ! for a variate, # for a variate, and $ for a text. For example

COLUMN=!T('Trt!','ID$','Rank#')

will create a factor called Trt, a text called ID and a variate called Rank. If only the type code is provided, the columns will not be renamed, but the new types will set, e.g.

COLUMN=!T('!','$','#')

will force the first three columns to be of type factor, variate and text respectively.

   (Note: DDEIMPORT replaces the procedure DDELOAD from earlier editions of GenStat.)

 

Options: PRINT, SHOW, IMETHOD.

Parameters: SERVER, TOPIC, ITEM, GDEFILE, COLUMNS, ISAVE.


Method

The DDE server is queried with the TOPIC and ITEM, and any data received from the DDE server is sent to a temporary GSH file which is read in with the SPLOAD directive.


Action with RESTRICT

Restrictions are not applicable to any of the parameters.