Meteorological Data Analysis Using MapReduce

Algorithm 1

map(String input_key, String input_value):

 //input_key: document name

 //input_value: document contents

 for each year 𝑦 and temperature 𝑡 in input_value:

EmitIntermediate(𝑦, 𝑡);

reduce(String output_key, Interator intermediate_values):

 // output_key: year

 // intermediate_values: a list of temperature

  int maxValue = Interger.MIN_VALUE;

  for each 𝑡 in intermediate_values:

  maxValue = Math.max(𝑡);

 Emit(year, maxValue);