如何使用IronPython从Spotfire中的临时文件读取大数据

Question

I need to read large data from temp file in Spotfire using IronPython.

First I have exported my Tibco data table in a temp file using the Exported text() method:

 #Temp file for storing the TablePlot data
tempFolder = Path.GetTempPath()
tempFilename = Path.GetTempFileName()

 #Export TablePlot data to the temp file
tp = tablePlotViz.As[TablePlot]()
writer = StreamWriter(tempFilename)
tp.ExportText(writer)

After that, opened the temp file using the open() method.

f = open(tempFilename)

Now when I started to read the data from the opened file and write back into a String variable then it is taking too much time. And my Spotfire screen is stopped working.

Has anyone idea about this?

My data table is of 8MB size.

Code is:

from Spotfire.Dxp.Application.Visuals import TablePlot, HtmlTextArea

import clr
import sys
clr.AddReference('System.Data')
import System
from System.Data import DataSet, DataTable, XmlReadMode
from Spotfire.Dxp.Data import DataType, DataTableSaveSettings
from System.IO import StringReader, StreamReader, StreamWriter, MemoryStream, SeekOrigin, FileStream, FileMode,Path, File
from Spotfire.Dxp.Data.Export import DataWriterTypeIdentifiers
from System.Threading import Thread
from Spotfire.Dxp.Data import IndexSet
from Spotfire.Dxp.Data import RowSelection
from Spotfire.Dxp.Data import DataValueCursor
from Spotfire.Dxp.Data import DataSelection
from Spotfire.Dxp.Data import DataPropertyClass
from Spotfire.Dxp.Data import Import

from Spotfire.Dxp.Data.Import import TextFileDataSource, TextDataReaderSettings
from System import Array
from Spotfire.Dxp.Application.Visuals import VisualContent
from Spotfire.Dxp.Application.Visuals import TablePlot
from System.IO import Path, StreamWriter
from System.Text import StringBuilder


 #Temp file for storing the TablePlot data
tempFolder = Path.GetTempPath()
tempFilename = Path.GetTempFileName()

 #Export TablePlot data to the temp file
tp = tablePlotViz.As[TablePlot]()
writer = StreamWriter(tempFilename)
tp.ExportText(writer)

#Build the table
sb = StringBuilder()

 #Open the temp file for reading
f = open(tempFilename)

#build the html table
html = " <TABLE id='table' style='display:none;'>\n"
html += "<THEAD>"
html += " <TR><TH>"
html += " </TH><TH>".join(f.readline().split("\t")).strip()
html += " </TH></TR>"
html += "</THEAD>\n"
html += "<TBODY>\n"

for line in f:
   html += "<TR><TD>"
   html += "</TD><TD>".join(line.split("\t")).strip()
   html += "</TD></TR>\n"


#Assigned the all HTML data in the text area
print html

The code works fine with short data.

Answer 1

If I am getting correctly, the intention behind the code is reading Table Plot visualization data into a string, for further using in a HTML Text Area. There is an alternative way for doing this, without writing data into temporary file. We can use memory stream to export data and convert exported text to string for further reuse. The sample code can be referred from here .