B4P Reference

Function Names

table extract

Description

This function extracts a sub-table from a table using coordinates of the sub-table. The coordinates are typically generated with the function table explore() and optionally filtered with table filter(). Alternatively, you can specify the coordinates directly.
Function 'table extract'

This function extracts exactly 1 table. If the coordinates describe more than 1 sub-table, then call this function for every sub-table using different index values to be specified in the 3rdfunction parameter.

Call as: procedure

Restrictions

Indirect parameter passing is disabled

Parameter count

4-6

Parameters

No.	Type	Description
1. input	string	Name of existing table This is the original table which contains at least one sub-table to extract
2. input	string	Name of destination table The extracted source table will be written into this table. The table will be created automatically if it is not yet existing Using appropriate offset values allows to add various sub-tables into one destination table, e.g. by arranging them next or below each other.
3. input	matrix of numerals	Coordinates of identified sub-tables The matrix of numerals is a set which contains 0, 1 or more sets where each of them refers to a found sub-table and contain 4 numerals marking top left and bottom right coordinates: { { x start, y start, x end, y end }, { x start, y start, x end, y end }, ... }. Normally, provide the return value from table explore() or table filter() in this parameter.
4. input	numeral	Index The index refers to one coordinate in the list of coordinates provided in the 3rd function parameter. The range is between 0 and coordinates[]{}-1 where coordinates[] is assumed to contain the list of coordinates. Note: Only one sub-table can be retrieved at a time.
Opt. 5. input	numeral	Row offset This value rules the vertical offset of the sub-table to be added in the destination table. Use 0 to write the table beginning on row 0, 1 on the next row below, etc. To append tables vertically, use the function table length() and add a small number on top in order to provide some accetable spacing. Default value: 0
Opt. 6. input	numeral	Column offset This value rules the horizontal offset of the sub-table to be added in the destination table. Use 0 to write the table starting at the leftmost column. Use larger nummbers to write the table further to the right. To append tables horizontally, use the function table row width() or table max width() and add a small number on top in order to provide some accetable spacing. Curiosity: If you use the starting coordinates, then you can place the sub-tables in their original positions in the new table, using the same horizontal and vartical offsets. Default value: 0

Examples

       table load( test, "Examples\Table Explore Demo.csv" );

       table list ( test );



       coords[] = table explore ( test );



       coords 1[] = table filter( test, coords[], 'Profession' );

       table extract( test, out, coords 1[], 0 );



       coords 2[] = table filter( test, coords[], 'Cities' );

       table extract( test, out, coords 2[], 0, 0, table row width(out) );



       echo("Extracted table containing 'Profession' and 'Cities' in headers");

       table list( out );

Output

    0 : Last Name | First Name | Town      |  |           | Family Name | First Name | Town      |  | Country
    1 : Andersson | Andy       | Boston    |  |           | Andersson   | Andy       | Boston    |  | USA    
    2 : Bethel    | Betty      | Cambridge |  |           | Bethel      | Betty      | Cambridge |  | U.S.   
    3 : Charlsson | Charles    | Baltimore |  |           |             |            |           |  |        
    4 : Dickson   | Dieter     | W. DC     |  |           |             |            |           |  |        
    5 :           |            |           |  |           | Given Name  | Profession |           |  |        
    6 : Emmerich  | Elana      | Brussels  |  |           | Girolamo    | Acteur     |           |  |        
    7 :           |            |           |  | Cities    | Dominique   | Dompteur   |           |  |        
    8 :           |            |           |  | Prague    | Dimitri     | Clown      |           |  |        
    9 :           |            |           |  | Warsaw    |             |            |           |  |        
   10 :           |            |           |  | Bucharest |             |            |           |  |        
   11 :           |            |           |  | Budapest  |             |            |           |  |        
   12 :           |            |           |  | Istanbul  |             |            |           |  |        
   13 :           |            |           |  | Cairo     |             |            |           |  |        

Extracted table containing 'Profession' and 'Cities' in headers
    0 : Given Name | Profession | Cities   
    1 : Girolamo   | Acteur     | Prague   
    2 : Dominique  | Dompteur   | Warsaw   
    3 : Dimitri    | Clown      | Bucharest
    4 :            |            | Budapest 
    5 :            |            | Istanbul 
    6 :            |            | Cairo

Try it yourself: Open LIB_Function_table_extract.b4p in B4P_Examples.zip. Decompress before use.

table extract ...