Data visualization and analysis at the University of Washington, Seattle.
ArqueroIntroducing ArqueroAn Illustrated Guide to Arquero VerbsTidy Data in JavaScriptWorking with Window QueriesArquero CookbookAdding Aggregate Functions to ArqueroArquero Roll-Up and Drill-DownArquero and Apache ArrowArquero and D3Multi-Line Chart Data PreparationPeeking into the Gaia Star Catalog
Arquero Row Manipulation
// adds a row, as key (a=4) not yet in data
data
.concat(aq.table({ a: [4], b: ['z'] }).antijoin(data, 'a'))
.view()
// does not add row, as key (a=3) already in data
data
.concat(aq.table({ a: [3], b: ['z'] }).antijoin(data, 'a'))
.view()
{
const y = aq.table({ a: [2, 3], b: ['z', 'z'] });
return data
.join_left(y, 'a', update(data, y))
.view();
}
// generate a join value specification that performs updates
// if a column is not defined in other, simply return the primary value
// if the secondary value is defined, return it
function update(table, other) {
return table.columnNames().reduce((values, name) => {
const f = `[${JSON.stringify(name)}]`;
values[name] = other.columnIndex(name) >= 0
? `(a, b) => b${f} === undefined ? a${f} : b${f}`
: `a => a${f}`;
return values;
}, {});
}
{
const y = aq.table({ a: [2, 3], b: ['z', 'z'] });
return data
.join_left(y, 'a', patch(data, y))
.view();
}
// generate a join value specification that performs patching
// if a column is not defined in other, simply return the primary value
// if the primary value is null/undefined, return the secondary value
function patch(table, other) {
return table.columnNames().reduce((values, name) => {
const f = `[${JSON.stringify(name)}]`;
values[name] = other.columnIndex(name) >= 0
? `(a, b) => a${f} == null ? b${f} : a${f}`
: `a => a${f}`;
return values;
}, {});
}
{
const z = aq.table({ a: [2, 3, 4], b: ['z', 'z', 'z'] });
return data
.join_full(z, 'a', update(data, z))
.view();
}
data
.antijoin(aq.table({ a: [2, 3] }), 'a')
.view()
data
.antijoin(aq.table({ a: [2, 3], b: ['b', 'b'] }), 'a')
.view()
data
.antijoin(aq.table({ a: [2, 3], b: ['b', 'b'] }), ['a', 'b'])
.view()
// add new table methods to column table prototype
Object.assign(aq.ColumnTable.prototype, {
delete(other, joinKey) { return this.antijoin(other, joinKey); },
insert(other, joinKey) { return this.concat(other.antijoin(this, joinKey)); },
patch(other, joinKey) { return this.join_left(other, joinKey, patch(this, other)); },
update(other, joinKey) { return this.join_left(other, joinKey, update(this, other)); },
upsert(other, joinKey) { return this.join_full(other, joinKey, update(this, other)); }
})
data
.insert(aq.table({ a: [4], b: ['z'] }))
.view()
data
.update(aq.table({ a: [2, 3], b: ['z', 'z'] }), 'a')
.view()
data
.patch(aq.table({ a: [2, 3], b: ['z', 'z'] }), 'a')
.view()
data
.upsert(aq.table({ a: [2, 3, 4], b: ['z', 'z', 'z'] }), 'a')
.view()
data
.delete(aq.table({ a: [2, 3] }))
.view()
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