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when executing the following code firebug tells me: values[this.geo.value] is undefined what is the problem?

$.get('./RDFexamples/tin00089_test2.rdf', null, function (rdfXml) {
var rdf, json = {};
var values = new Array();

rdf = $.rdf()
    .load(rdfXml)
    .prefix('', '')
    .prefix('qb', '')
    .prefix('rdf', '')
    .prefix('dcterms', '/')
    .prefix('sdmx-measure', '')
    .where('?observation a qb:Observation')
    .where('?observation dcterms:date ?date')
    .where('?observation sdmx-measure:obsValue ?measure')
    .where('?observation :geo ?geo')
    .each(function () {
        values[this.geo.value].push(this.measure.value);
        //alert(this.date.value)
        //alert(this.measure.value)
        //alert(this.geo.value)
    }
    );
    alert(values);
});

when executing the following code firebug tells me: values[this.geo.value] is undefined what is the problem?

$.get('./RDFexamples/tin00089_test2.rdf', null, function (rdfXml) {
var rdf, json = {};
var values = new Array();

rdf = $.rdf()
    .load(rdfXml)
    .prefix('', 'http://ontologycentral./2009/01/eurostat/ns#')
    .prefix('qb', 'http://purl/linked-data/cube#')
    .prefix('rdf', 'http://www.w3/1999/02/22-rdf-syntax-ns#')
    .prefix('dcterms', 'http://purl/dc/terms/')
    .prefix('sdmx-measure', 'http://purl/linked-data/sdmx/2009/measure#')
    .where('?observation a qb:Observation')
    .where('?observation dcterms:date ?date')
    .where('?observation sdmx-measure:obsValue ?measure')
    .where('?observation :geo ?geo')
    .each(function () {
        values[this.geo.value].push(this.measure.value);
        //alert(this.date.value)
        //alert(this.measure.value)
        //alert(this.geo.value)
    }
    );
    alert(values);
});

• javascript
• jquery
• arrays
• undefined

Share Improve this question Follow edited Jun 16, 2011 at 9:05 Gaurav Saxena 15711 silver badge66 bronze badges asked Jun 16, 2011 at 8:55 betabeta 5,7061616 gold badges6363 silver badges113113 bronze badges

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2 Answers 2

Sorted by: Reset to default 3

values[this.geo.value] is never initialized so you can't do .push because values[this.geo.value] is undefined, you first need to create an array in values[this.geo.value] before you can push things into it.

Pseudo-code example

if values[this.geo.value] == undefined {
    values[this.geo.value] = []
}
values[this.geo.value].push(...)

push is a method of the Array object itself - you are calling it on a value within the Array (which has probably not been set, hence 'undefined'). It's unclear what this.geo.value is, but assuming its the index of the array item you are trying to set, your options are:

values.push(this.measure.value);

or

values[this.geo.value] = this.measure.value;

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