datasets (Tablesaw) - axkr/symja_android_library GitHub Wiki
The Dataset
type is implemented with the tablesaw dataframe library
Dataset
objects can be created with SemanticImport and SemanticImportString functions.
>> ds=SemanticImportString("Products,Sales,Market_Share
a,5500,3
b,12200,4
c,60000,33")
Select a single column:
>> ds(All, "Market_Share")
Select a single element:
>> ds(3, 2)
Select a row and return the result as an association
>> ds(2) // Normal
<|Products->b,Sales->12200,Market_Share->4|>
Dataset rows can be selected.
>> ds(Select(#Sales < 13000 &), {"Products", "Market_Share"})
With the `Normal' function the Dataset can be converted into a Symja expression.
>> ds(All, "Sales") // Normal
{5500,12200,60000}
Compute number of times an element is available in the column
>> ds(Counts, "Sales")
<|60000->1,12200->1,5500->1|>
Compute the sum of a column
>> ds(Total, "Sales")
77700
Join the strings of a column
>> ds(StringJoin, "Products")
abc
check("ds(StringJoin, \"Products\")", //
"abc");