Kata

dataand data1 are two strings with rainfall records of a few cities for months from January to December. The records of towns are separated by \n. The name of each town is followed by :.

data and towns can be seen in "Your Test Cases:".

Task:

• function: mean(town, strng) should return the average of rainfall for the city town and the strng data or data1 (In R and Julia this function is called avg).
• function: variance(town, strng) should return the variance of rainfall for the city town and the strng data or data1.

Examples:

mean("London", data), 51.19(9999999999996) 
variance("London", data), 57.42(833333333374)

Notes:

• if functions mean or variance have as parameter town a city which has no records return -1 or -1.0 (depending on the language)

• Don't truncate or round: the tests will pass if abs(your_result - test_result) <= 1e-2 or abs((your_result - test_result) / test_result) <= 1e-6 depending on the language.

• Shell

  1. Shell tests only variance.
  2. In "function "variance" $1 is "data", $2 is "town".

• A ref: http://www.mathsisfun.com/data/standard-deviation.html

• data and data1 (can be named d0 and d1 depending on the language; see "Sample Tests:") are adapted from: http://www.worldclimate.com