R Programming for Biologists

Teaching the tools to get computers to do cool science

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Expressions and Variables

Modify the Code


The following code calculates the total net primary productivity (NPP) per day for two sites based on the grams of carbon produced per square meter per day, and the total area of the sites, and prints them out.

site1_g_carbon_m2_day <- 5
site2_g_carbon_m2_day <- 2.3
site1_area_m2 <- 200
site2_area_m2 <- 450
site1_npp_day <- site1_g_carbon_m2_day * site1_area_m2
site2_npp_day <- site2_g_carbon_m2_day * site2_area_m2
site1_npp_day
site2_npp_day

Modify the code to produce the following items and print them out in order:

  1. The sum of the total daily NPP for the two sites combined.
  2. The difference between the total daily NPP for the two sites. We only want an absolute difference, so use abs() function to make sure the number is positive.
  3. The total NPP over a year for the two sites combined.