Check if the differences between elements of a vector are constant

check_diff_constant() and check_is_diff_constant() verify if the differences between elements of a numeric vector are constant. check_diff_constant() raises an error if the differences are not constant, while check_is_diff_constant() returns TRUE if the differences are constant and FALSE otherwise.

Usage

check_diff_constant(vec, n = 2, tol = 1e-16, par_name = "vec")

check_is_diff_constant(vec, n = 2, tol = 1e-16)

Arguments

vec

A numeric vector to check for constant differences.

n

Integer specifying the number of times to perform differencing. Default is 2.

tol

Numeric tolerance level to determine constant differences. Default is 1e-16.

par_name

An optional name of the parameter to display in error messages.

Value

• check_diff_constant(): Returns the original vector if the differences are constant or raises an error if they are not.

• check_is_diff_constant(): Logical value, TRUE if the differences are constant, and FALSE otherwise.

Examples

# Examples for check_diff_constant()
# ----------------------------------

vec1 <- c(1, 3, 5, 7)
print(vec1)
#> [1] 1 3 5 7
check_diff_constant(vec1)
#> [1] 1 3 5 7

vec2 <- c(2, 4, 8, 16)
print(vec2)
#> [1]  2  4  8 16
try(check_diff_constant(vec2))
#> Error in check_diff_constant(vec2) : 
#>   Difference between elements of 'vec' must be constant, but got 2, 4, 8, 16

vec3 <- seq(10, 20, by = 2)
print(vec3)
#> [1] 10 12 14 16 18 20
check_diff_constant(vec3)
#> [1] 10 12 14 16 18 20

vec4 <- c(1, 2, 3, 4, 7)
print(vec4)
#> [1] 1 2 3 4 7
try(check_diff_constant(vec4))
#> Error in check_diff_constant(vec4) : 
#>   Difference between elements of 'vec' must be constant, but got 1, 2, 3, 4, 7

vec5 <- c(0.1, 0.2, 0.3, 0.4)
print(vec5)
#> [1] 0.1 0.2 0.3 0.4
check_diff_constant(vec5, tol = 1e-15)
#> [1] 0.1 0.2 0.3 0.4

# Examples for check_is_diff_constant()
# -------------------------------------

check_is_diff_constant(vec1)
#> [1] TRUE

check_is_diff_constant(vec2)
#> [1] FALSE

check_is_diff_constant(vec3)
#> [1] TRUE

check_is_diff_constant(vec4)
#> [1] FALSE

check_is_diff_constant(vec5, tol = 1e-15)
#> [1] TRUE