42 lines
1.2 KiB
R
42 lines
1.2 KiB
R
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# Goals: To write functions
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# To write functions that send back multiple objects.
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# FIRST LEARN ABOUT LISTS --
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X = list(height=5.4, weight=54)
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print("Use default printing --")
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print(X)
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print("Accessing individual elements --")
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cat("Your height is ", X$height, " and your weight is ", X$weight, "\n")
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# FUNCTIONS --
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square <- function(x) {
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return(x*x)
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}
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cat("The square of 3 is ", square(3), "\n")
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# default value of the arg is set to 5.
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cube <- function(x=5) {
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return(x*x*x);
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}
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cat("Calling cube with 2 : ", cube(2), "\n") # will give 2^3
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cat("Calling cube : ", cube(), "\n") # will default to 5^3.
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# LEARN ABOUT FUNCTIONS THAT RETURN MULTIPLE OBJECTS --
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powers <- function(x) {
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parcel = list(x2=x*x, x3=x*x*x, x4=x*x*x*x);
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return(parcel);
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}
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X = powers(3);
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print("Showing powers of 3 --"); print(X);
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# WRITING THIS COMPACTLY (4 lines instead of 7)
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powerful <- function(x) {
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return(list(x2=x*x, x3=x*x*x, x4=x*x*x*x));
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}
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print("Showing powers of 3 --"); print(powerful(3));
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# In R, the last expression in a function is, by default, what is
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# returned. So you could equally just say:
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powerful <- function(x) {list(x2=x*x, x3=x*x*x, x4=x*x*x*x)}
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