TeeChart Example?

waeberd

Hi,

I have filled a db table with some demo data:

<!--fonto:Lucida Console--><span style="font-family:Lucida Console"><!--/fonto-->CARS PHONES MONITORS LAMPS
44 852 834 973
843 962 600 351
958 650 998 541
<!--fontc--></span><!--/fontc-->

Now I would like to get a chart in FastReport with those 3 series.
I don't get it, folks... how can I do this using the TfrxChart wrapper?
I would like to do a "radar series" and I am using TeeChart PRO 8, but this
is probably unimportant..

Do I need to add series by script?

Any hint is very welcome, thanks a lot
Daniel

waeberd

Ok, I have found out the following:

* FastReport expects one db-rowset per teechart-series
* for radar series FastReport expects a "LABEL / ANGLE / VALUE" rowformat

Consequences:
* I need one query per series
* if I want to use radar series, I need to change the sql from

SELECT *
  FROM teechartdata
 WHERE teechartdata_id = 10

to

SELECT   *
    FROM (SELECT 'Cars' label, 0 angle, cars VALUE
            FROM teechartdata
           WHERE teechartdata_id = 10
          UNION
          SELECT 'Phones' label, 72 angle, phones VALUE
            FROM teechartdata
           WHERE teechartdata_id = 10
          UNION
          SELECT 'Tables' label, 144 angle, TABLES VALUE
            FROM teechartdata
           WHERE teechartdata_id = 10
          UNION
          SELECT 'Monitors' label, 216 angle, monitors VALUE
            FROM teechartdata
           WHERE teechartdata_id = 10
          UNION
          SELECT 'Lamps' label, 288 angle, lamps VALUE
            FROM teechartdata
           WHERE teechartdata_id = 10)
ORDER BY angle

... which is of course very bad SQL-coding (too complicated, too many queries).

How can I simplify this? Read the data from the simple "SELECT *" query and add the series-data
by script?

Please help!

Daniel

gordk

create the series in the chart editor
then in the onbeforeprintmethod of the chart object.
use the add method to add values to each series.
tip you can connect the query to a hiddendataband set to 1 record
then in the obpevent of the chart object write code to iterate through the dataset and add the values to the series'.
begin
masterdata1.dataset.first;
for i = 0 to masterdata1.dataset.recordcount-1 do
begin
code to add values to series[0];
code to add values to series[1];
code to add values to series[2];
masterdata1.dataset.next;
next;
end;
see the usermanual on working with charts.

waeberd

Excellent, thanks for pointing the directions, Gord!

works fine, here's my scripting code (in case somebody's interested... :-) ):

procedure BuildRadarSeries(series: TfrxSeriesItem);
var
  j: integer;
  nAngle: integer;                                     
  strSep: string;
  qry: TfrxODACQuery;
  strFieldName: string;                                               
begin
  strSep := '';
  qry := TfrxODACQuery(invisibleBand.Dataset);                               
  if qry.FieldsCount > 0 then
    nAngle := 360 div qry.FieldsCount
  else
    nAngle := 0;                                                 
  for j := 0 to qry.FieldsCount -1 do
  begin
    strFieldName := qry.Fields[j].FieldName;
    { Source1: "LABEL"}                                                           
    series.Source1 := series.Source1 + strSep + strFieldName;                                                                                                                                                           
    { Source2: "ANGLE"}                                                           
    series.Source2 := series.Source2 + strSep + IntToStr(j * nAngle);
    { Source3: "VALUE"}                                                           
    series.Source3 := series.Source3 + strSep + IntToStr(qry.Value[strFieldName]);                                                                                                                                                           
    strSep := ';';                                        
  end;                  
end;


procedure Chart1OnBeforePrint(Sender: TfrxComponent);
var
  i: integer;                                
begin
  i := 0;                             
  with invisibleBand.Dataset do
  begin                    
    First;
    while not eof do
    begin
      BuildRadarSeries(Chart1.SeriesData[i]);                                                                         
      Inc(i);                      
      Next;
    end;  
  end;              
end;

begin

end.

Cheers, Daniel