Each type has it own Null value. You can create one with the following function Value.getNullValueFromValueType http://www.google.com/codesearch/p?hl=en#aLJwv4TSmDw/trunk/src/main/java/com/google/visualization/datasource/datatable/value/Value.java&q=getNullValueFromValueType&sa=N&cd=1&ct=rc
On Sat, Feb 6, 2010 at 3:05 AM, carlos <[email protected]> wrote: > I am being unclear: What I can't figure out, is a way to insert null > values into the DataTable itself. I need a function in the datasource > API that a) sets an arbitrary value in a datatable (I don't see a > setvalue() function anywhere in the api), or b) a function that allows > you to set a null value in the data table. Or c) maybe I need to use > a different type besides NUMBER? > > I passed a null value to the addCell() method by casting null to a > Double: addCell((Double)null). Unfortunately generateDataTable() > throws a 'nulll pointer exception' when I do this. > > To create a 2x3 data table with the datasource api I did the > following. Let's say for this example that I want the first cell to > be null but everything else to have a numerical value. Thanks for > your help! > > DataTable data = new DataTable(); > data.addColumn(new ColumnDescription("col1",ValueType.NUMBER,"col1")); > data.addColumn(new ColumnDescription("col2",ValueType.NUMBER,"col2")); > data.addColumn(new ColumnDescription("col3",ValueType.NUMBER,"col3")); > > TableRow tr = new TableRow(); > tr.addCell(0); // I want to make this cell null! > tr.addCell(1); > tr.addCell(1); > > data.addRow(tr); > > TableRow tr2 = new TableRow(); > tr2.addCell(2); > tr2.addCell(3); > tr2.addCell(3); > > On Feb 5, 10:09 am, ChartMan <[email protected]> wrote: > > Null cells will be omitted from the data table json response (replaced > with > > commas ,,,) > http://www.google.com/codesearch/p?hl=en#aLJwv4TSmDw/trunk/src/java/c... > > > > <http://www.google.com/codesearch/p?hl=en#aLJwv4TSmDw/trunk/src/java/c.. > .>As > > for null rows, I am quite sure you can omit them from the json response > but > > it seems that the library does not do that for you. > > > > ChartMan > > > > > > > > On Fri, Feb 5, 2010 at 4:54 AM, carlos <[email protected]> wrote: > > > Sorry, I don't quite follow. I'm using the Java namespace > > > com.google.visualization.datasource.datatable to generate a data table > > > that will get output as json. The only way I see to build a table is > > > to addRow(Row r). and the only way to build a row, is to serially add > > > cells. r.addcell(). Am I missing something? Is there a way to set > > > the value of a certain cell? > > > > > -Carlos > > > > > On Feb 4, 2:28 am, ChartMan <[email protected]> wrote: > > > > don't add anything to rows/cells that are empty. This will result in > > > empty > > > > sections of the json. > > > > E.g., {v:1},,,,,,,,,{v:2} > > > > > > ChartMan > > > > > > On Thu, Feb 4, 2010 at 6:44 AM, carlos <[email protected]> wrote: > > > > > I am writing a datasource in java to feed data to a scatterplot > from a > > > > > mysql database. The data is sparse: not every column has a value > for > > > > > every row. I can easily plot sparse data manually in javascript or > in > > > > > the java GWT by only setting certain values in a DataTable. Is > there > > > > > a way to generate sparse data from a servlet with the > Visualization- > > > > > DataSource java API? > > > > > > > Using addCell to add an empty string to numerical data throws an > > > > > error. > > > > > > > Thanks, > > > > > Carlos > > > > > > > -- > > > > > You received this message because you are subscribed to the Google > > > Groups > > > > > "Google Visualization API" group. > > > > > To post to this group, send email to > > > > > [email protected]. > > > > > To unsubscribe from this group, send email to > > > > > [email protected]<google-visualization-api%[email protected]><google-visualization- > api%[email protected] <api%[email protected]> > ><google-visualization- > > > api%[email protected]<api%[email protected]>< > api%[email protected]<api%[email protected]> > >> > > > > > . > > > > > For more options, visit this group at > > > > >http://groups.google.com/group/google-visualization-api?hl=en. > > > > > -- > > > You received this message because you are subscribed to the Google > Groups > > > "Google Visualization API" group. > > > To post to this group, send email to > > > [email protected]. > > > To unsubscribe from this group, send email to > > > [email protected]<google-visualization-api%[email protected]><google-visualization- > api%[email protected] <api%[email protected]>> > > > . > > > For more options, visit this group at > > >http://groups.google.com/group/google-visualization-api?hl=en. > > -- > You received this message because you are subscribed to the Google Groups > "Google Visualization API" group. > To post to this group, send email to > [email protected]. > To unsubscribe from this group, send email to > [email protected]<google-visualization-api%[email protected]> > . > For more options, visit this group at > http://groups.google.com/group/google-visualization-api?hl=en. > > -- You received this message because you are subscribed to the Google Groups "Google Visualization API" group. 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