Filtering Rows in a Grid

Alters the table's results (i.e., 'statistics') so that each row (soft drink brand) is showing statistics filtered to respondents that prefer the brand.

It does this by finding filters that have the same name as the brand name shown in the rows of the table.

This example can be run using the question Brand Associations in C:\Program Files\Q\Examples\Cola.Q (this file may be in a different place on your computer).

The explanation for how this example works is contained in comments within the code snippet below. However, a few additional things to note:

• To check this code has worked, select Statistics - Cells : Base n.
• The variables that are being used as the filters are not set up in Q as filters. That is, they are not tagged with the in the Variables and Questions tab.

This script will cause significance results to be displayed incorrectly. Please read Caveats for Table JavaScript before using this script.

var brands_to_filter = {
    'Coke': 'CokePreferred',
    'Diet Coke': 'DietCokePreferred',
    'Coke Zero': 'CokeZeroPreferred',
    'Pepsi': 'PepsiPreferred',
    'Diet Pepsi': 'PepsiLightPreferred',
    'Pepsi Max': 'PepsiMaxPreferred',
    'None of these': 'Indifferent'
};

var brands = table.rowLabels;// The row labels (brand names).
for (var row = 0; row < table.numberRows; row++) {// For each row (brand)...
    var filters = ['!UseQFilters'];//get any existing filters for the table
    var brand_filter = brands_to_filter[brands[row]];// Find the name of the filter with the same label as the row
    if (brand_filter) //add the brand filter to the list of filters
        filters.push(brand_filter);
    var brand_table = calculateTable(table.blue, table.brown, filters, '!UseQWeight');// Run the table.
    // Copy the statistics for this row (brand) from the filtered table to the main table
    var stats = table.statistics;
    for (var stat = 0; stat < stats.length; stat++) {//looping through all the statistics on the table
        var filtered_values = brand_table.get(stats[stat]);// Get the values from the filtered table.
        var main_values = table.get(stats[stat]);// Get the values from the main table.
        // Copy the values from the filtered table to the main table for this row/brand
        for (var column = 0; column < table.numberColumns; column++)
            main_values[row][column] = filtered_values[row][column];
        table.set(stats[stat], main_values);// Set the altered values to the main table.
    }
}

See also

• Table JavaScript and Plot JavaScript for an explanation of how to run this code.
• Table JavaScript and Plot JavaScript Reference for technical information.
• Table JavaScript and Plot JavaScript Examples Library for other examples.
• JavaScript for information about the JavaScript programming language.
• QScript for tools for automating projects using JavaScript.
• JavaScript Variables for detail on how to create new variables in the Variables and Questions tab using JavaScript.