title: maxIter parameter in spark ml.classification
body: <p>What is the role of the <code>maxIter</code> parameter used in LogisticRegression from <code>pyspark.ml.classification</code>?.</p>
  
  <pre><code>mlor = LogisticRegression(maxIter=5, regParam=0.01, weightCol="weight",
       family="multinomial")
  </code></pre>