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extensionmodelnode properties
Last updated: Jan 17, 2024
extensionmodelnode properties

Extension Model node iconWith the Extension Model node, you can run R or Python for Spark scripts to build and score results.

Note that many of the properties and much of the information on this page is only applicable to SPSS Modeler Desktop streams.

Python for Spark example

import modeler.api
stream = modeler.script.stream()
node = stream.create("extension_build", "extension_build")
node.setPropertyValue("syntax_type", "Python")

build_script = """
import json
import spss.pyspark.runtime
from pyspark.mllib.regression import LabeledPoint
from pyspark.mllib.linalg import DenseVector
from pyspark.mllib.tree import DecisionTree

cxt = spss.pyspark.runtime.getContext()
df = cxt.getSparkInputData()
schema = df.dtypes[:]

target = "Drug"
predictors = ["Age","BP","Sex","Cholesterol","Na","K"]

def metaMap(row,schema):
    col = 0
    meta = []
    for (cname, ctype) in schema:
        if ctype == 'string':
            meta.append(set([row[col]]))
        else:
            meta.append((row[col],row[col]))
        col += 1        
    return meta

def metaReduce(meta1,meta2,schema):
    col = 0
    meta = []
    for (cname, ctype) in schema:
        if ctype == 'string':
            meta.append(meta1[col].union(meta2[col]))
        else:
            meta.append((min(meta1[col][0],meta2[col][0]),max(meta1[col][1],meta2[col][1])))
        col += 1
    return meta

metadata = df.rdd.map(lambda row: metaMap(row,schema)).reduce(lambda x,y:metaReduce(x,y,schema))

def setToList(v):
    if isinstance(v,set): 
        return list(v)
    return v

metadata = map(lambda x: setToList(x), metadata)
print metadata

lookup = {}
for i in range(0,len(schema)):
    lookup[schema[i][0]] = i

def row2LabeledPoint(dm,lookup,target,predictors,row):
    target_index = lookup[target]
    tval = dm[target_index].index(row[target_index])
    pvals = []
    for predictor in predictors:
        predictor_index = lookup[predictor]
        if isinstance(dm[predictor_index],list):        
            pval = dm[predictor_index].index(row[predictor_index])
        else:
            pval = row[predictor_index]
        pvals.append(pval)
    return LabeledPoint(tval,DenseVector(pvals))

# count number of target classes
predictorClassCount = len(metadata[lookup[target]])

# define function to extract categorical predictor information from datamodel 
def getCategoricalFeatureInfo(dm,lookup,predictors):
    info = {}
    for i in range(0,len(predictors)):
        predictor = predictors[i]
        predictor_index = lookup[predictor]
        if isinstance(dm[predictor_index],list):
            info[i] = len(dm[predictor_index])
    return info

# convert dataframe to an RDD containing LabeledPoint
lps = df.rdd.map(lambda row: row2LabeledPoint(metadata,lookup,target,predictors,row))

treeModel = DecisionTree.trainClassifier(
    lps,
    numClasses=predictorClassCount,
    categoricalFeaturesInfo=getCategoricalFeatureInfo(metadata, lookup, predictors),
    impurity='gini',
    maxDepth=5,
    maxBins=100)

_outputPath = cxt.createTemporaryFolder()
treeModel.save(cxt.getSparkContext(), _outputPath)
cxt.setModelContentFromPath("TreeModel", _outputPath)
cxt.setModelContentFromString("model.dm",json.dumps(metadata), mimeType="application/json")\
   .setModelContentFromString("model.structure",treeModel.toDebugString())

"""

node.setPropertyValue("python_build_syntax", build_script)

R example

node.setPropertyValue("syntax_type", "R")
node.setPropertyValue("r_build_syntax", """modelerModel <- lm(modelerData$Na~modelerData$K,modelerData)
modelerDataModel
modelerModel 
""")
Table 1. extensionmodelnode properties
extensionmodelnode Properties Values Property description
syntax_type R Python Specify which script runs: R or Python (R is the default).
r_build_syntax string The R scripting syntax for model building.
r_score_syntax string The R scripting syntax for model scoring.
python_build_syntax string The Python scripting syntax for model building.
python_score_syntax string The Python scripting syntax for model scoring.
convert_flags StringsAndDoubles
LogicalValues
Option to convert flag fields.
convert_missing flag Option to convert missing values to R NA value.
convert_datetime flag Option to convert variables with date or datetime formats to R date/time formats.
convert_datetime_class
POSIXct

POSIXlt
Options to specify to what format variables with date or datetime formats are converted.
output_html flag Option to display graphs in the R model nugget.
output_text flag Option to write R console text output to the R model nugget.
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