Spotfire 从 python 列表中添加列

Question

如何将 python 列表作为新列添加到 spotfire 数据表中。例如，我希望添加一个具有使用 python 计算的值的列。

from Spotfire.Dxp.Data import *

# Get the data table
DataTable = Document.Data.Tables.TryGetValue("Table Name")[1]

# define some cursors
CursorA = DataValueCursor.CreateFormatted(DataTable.Columns["Column A"])
CursorB = DataValueCursor.CreateNumeric(DataTable.Columns["Column B"])
CursorC = DataValueCursor.CreateNumeric(DataTable.Columns["Column C"])

# define a list
NewColumnValues = []

# Go row by row and calculate the values I want.
for row in DataTable.GetRows(CursorA, CursorB, CursorC):
    A = CursorA.CurrentValue
    B = CursorB.CurrentValue
    C = CursorC.CurrentValue
    V = SomeComplicatedFunction(A, B, C)
    NewColumnValues.append(V)

# And now add that column to the datatable
# If only it would work like this...
DataTable.AddColumns('NewColumnName', NewColumnValues)

有没有办法做到这一点？我能看到的使用 AddColumns 方法的唯一示例涉及添加从另一个文件读取的列，我不知道如何使它们工作。

Answer 1

我已经破解了它，并从这个相关解决方案中获得了一些指导：How to create a data table on the fly in Spotfire via python

简短的回答是，您不能直接从 python 列表中添加一列，但您可以创建一个文本对象并直接从中导入，而无需将其保存在任何地方。

这是脚本的外观。

from Spotfire.Dxp.Data import *
from System.IO import StringReader, StreamReader, StreamWriter, MemoryStream, SeekOrigin
from Spotfire.Dxp.Data.Import import *

# Get the data table
DataTable = Document.Data.Tables.TryGetValue("Table Name")[1]

# define some cursors
CursorA = DataValueCursor.CreateFormatted(DataTable.Columns["Column A"])
CursorB = DataValueCursor.CreateNumeric(DataTable.Columns["Column B"])
CursorC = DataValueCursor.CreateNumeric(DataTable.Columns["Column C"])
CursorRowId = DataValueCursor.CreateNumeric(DataTable.Columns["Row ID"])
# Note that column "Row ID" must be a unique identifier, and it can't be a calculated field (even a frozen one).

textData = ""
# Go row by row and calculate the values I want.
    for row in DataTable.GetRows(CursorA, CursorB, CursorC, CursorRowId):
    A = CursorA.CurrentValue
    B = CursorB.CurrentValue
    C = CursorC.CurrentValue
    V = SomeComplicatedFunction(A, B, C)
    textData += "%d\t%f\r\n" % (CursorRowId, V)

# So now textData is a two column text string containing all the data I need.
# Turn it into an in-memory text data source.

stream = MemoryStream()
writer = StreamWriter(stream)
writer.Write(textData)
writer.Flush()
stream.Seek(0, SeekOrigin.Begin)

readerSettings = TextDataReaderSettings()
readerSettings.Separator = "\t"
readerSettings.SetDataType(0, DataType.String)
readerSettings.SetColumnName(0, 'Row ID')
readerSettings.SetDataType(1, DataType.Real)
readerSettings.SetColumnName(1, 'Calculated Value')

NewInfo = TextFileDataSource(stream, readerSettings)

# Define the table relationship
leftColumnSignature = DataColumnSignature("Row ID", DataType.Integer)
rightColumnSignature = DataColumnSignature("Row ID", DataType.Integer)
columnMap = {leftColumnSignature:rightColumnSignature}
ignoredColumns = []
columnSettings = AddColumnsSettings(columnMap, JoinType.LeftOuterJoin, ignoredColumns)

# Add the column
DataTable.AddColumns(NewInfo, columnSettings)

这将创建一个名为“计算值”的新列。