Open Settings

Frequently Asked Questions (FAQ)

On this page we will try to answer the remaining questions, which we were not yet able to answer on the HowTo page. Please let us know in case we forgot to explain something. Our contact information can be found on the CubeViz Project Page.

Q1: Why do I sometimes receive an empty chart?

This behavior can have various reasons. On the one hand it is possible that there is no data available according to the selection. In order to reduce the load of the server we decided not to check the availability of data for every selection. On the other hand it is possible that a chart can not be produced if the user selects inapplicable combinations of options such as a logarithm scale in combination with percentage stacking. Trapping such cases is not yet fully implemented but will be done soon.

To solve such problems we suggest to change the selection and/or the selected chart options.

Q2: Why do values of observations sometimes have so many digits after the decimal point. Doesn’t it fit to use only four or five digits?

We use the data as it is represented in the DataCube. We do not want to manipulate anything on the data side. In some domains much digits after the decimal point could be very interesting. CubeViz is a generic tool and we do not know anything about the domain represented in the Cube. We only know the vocabulary which is used to represent statistics.

Q3: Sometimes I am able to create a pie-chart and sometimes I am not. Why am I not able to always generate the same chart?

CubeViz contains an algorithm to analyze the selection of data in order to offer suitable charts. Some of the charts are an unsuitable or an inappropriate choice for the respective data selection. The pie-chart, for instance, is only available if the user selects multiple elements only from one dimension. The amount of elements from all other dimensions must be exactly one.

Q4: Why is it not possible to select slices in order to filter the DataCube more detailed?

DataCube is still under development, which means that we do not support that feature at the moment, but it will come soon. DataCubes that contain slices should be able to browse with CubeViz. It is only not possible to filter in such a fine-grained way.

Q5: Why isn’t it possible to compare different datasets?

The current version of CubeViz do not support that feature. The user is only able to make a single selection of Datasets. But we are working on getting this feature being an integral part of CubeViz in the near future.

Q6: Sometimes the User Interface is not updated. What should I do?

Sometimes the browser session is lost. Maybe you didn’t make an action for a long time. To get CubeViz running again, please reload CubeViz in the browser (In most browsers you only have to press F5 or Ctrl+R). If you do not want to loose your data selection, please use the Permalink for the reload.

Q7: Sometimes I have to wait a long time until the Chart is updating. What is the reason for that?

This behavior can have multiple reasons. On specific timespans you are not the only user who is visiting our web sites. That can lead to a high load on the server and users have to share processing times.
Another reason could be that you made an inadequate selection. If you select to much data items the server respond with a huge set of information which has to be transfered and processed by your browser. In such a case we suggest to deselect some of the items. Note that a chart will be not be well-arranged if too much information is included.

Q8: There is a tabular visualization in the list. What is it about?

In addition to the chart visualizations it should be possible to obtain the raw data. On the basis of this visualization type you are able to follow the links to the respective original data source. Note that these links are outgoing links.

Q9: Why do the colors of data items represented in charts sometimes leave room for improvement?

CubeViz provides an algorithm to generate colors in a deterministic way on the basis of identifiers of the underlying data items. This enables users to re-identify data items over different selections and charts. In case that we do not know anything about the domain of the data we are not able to create fix mappings between colors and the elements to be visualized. The result out of that algorithm is not always perfect, but without any color collapses.

Q10: Is it possible to download my selection as raw data?

Yes it is. After the user selected data and receives a chart, two buttons occur below the chart. Both lead to a raw data representation of her selection. The first one lead to a turtle representation, the second one be used to download a CSV file, that can be imported in well known spread sheet tools.

CubeViz

Sparql Endpoints

Select a datasource (SPARQL endpoint):


or add a data source (SPARQL endpoint)

 Example: http://fts.publicdata.eu/sparql

 Models of selected SPARQL endpoint