Add new rows to pyspark Dataframe

From something I did, using union, showing a block partial coding - you need to adapt of course to your own situation:

val dummySchema = StructType(
StructField("phrase", StringType, true) :: Nil)
var dfPostsNGrams2 = spark.createDataFrame(sc.emptyRDD[Row], dummySchema)
for (i <- i_grams_Cols) {
    val nameCol = col({i})
    dfPostsNGrams2 = dfPostsNGrams2.union(dfPostsNGrams.select(explode({nameCol}).as("phrase")).toDF )
 }

union of DF with itself is the way to go.

As thebluephantom has already said union is the way to go. I'm just answering your question to give you a pyspark example:

# if not already created automatically, instantiate Sparkcontext
spark = SparkSession.builder.getOrCreate()

columns = ['id', 'dogs', 'cats']
vals = [(1, 2, 0), (2, 0, 1)]

df = spark.createDataFrame(vals, columns)

newRow = spark.createDataFrame([(4,5,7)], columns)
appended = df.union(newRow)
appended.show()

Please have also a lookat the databricks FAQ: https://kb.databricks.com/data/append-a-row-to-rdd-or-dataframe.html