Data Science for Agriculture

How to manage and manipulate data for agricultural research

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Vectors

NDVI


The Normalized Difference Vegetation Index (NDVI) has been measured by your field crew on fields across the wheat belt in Oklahoma. The NDVI values have been entered into the following vector in order of sampling and fields are numbered starting at one. Cut and paste the list into your assignment and then answer the following questions by printing them to the screen. Some R functions that may come in handy include length(), max(), min(), mean(), head(), and tail().

ndvi <- c(0.58, 0.85, 0.73, 0.88, 0.89, 0.66, 0.81, 0.87,  
0.74, 0.8, 0.65, 0.64, 0.88, 0.63, 0.54, 0.67, 0.53, 0.82, 0.8, 
0.62, 0.78, 0.56, 0.57, 0.8, 0.56, 0.53, 0.54, 0.83, 0.57, 0.79, 
0.61, 0.58, 0.85, 0.85, 0.82, 0.83, 0.65, 0.71, 0.74, 0.81, 0.75, 
0.88, 0.65, 0.73, 0.63, 0.67, 0.73, 0.53, 0.68, 0.84, 0.67, 0.67, 
0.64, 0.55, 0.61, 0.8, 0.61, 0.83, 0.6, 0.89, 0.64, 0.63, 0.67, 
0.58, 0.56, 0.54, 0.79, 0.5, 0.55, 0.72, 0.69, 0.64, 0.82, 0.58, 
0.59, 0.88, 0.78, 0.52, 0.7, 0.84, 0.61, 0.87, 0.5, 0.6, 0.66, 
0.87, 0.52, 0.66, 0.82, 0.8, 0.65, 0.51, 0.84, 0.63, 0.87, 0.79)
  1. How many fields were measured?
  2. What was NDVI at field 37?
  3. What was NDVI at the last field? Have the computer choose the last field automatically in some way, not by manually entering its position.
  4. What is the lowest NDVI measured?
  5. What is the highest NDVI measured?
  6. What is the average NDVI measured across all fields?
[click here for output]