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Scale a numeric vector from 0 to 1

Source: R/jamba.r
normScale.Rd

Scale a numeric vector from 0 to 1

Usage

normScale(
  x,
  from = 0,
  to = 1,
  low = min(x, na.rm = TRUE),
  high = max(x, na.rm = TRUE),
  naValue = NA,
  singletMethod = c("mean", "min", "max"),
  ...
)

Arguments

x

numeric vector.

from

the minimum numeric value to re-scale the input numeric vector.

to

the maximum numeric value to re-scale the input numeric vector.

low

numeric value defining the low end of the input numeric range, intended when input values might not contain the entire numeric range to be re-scaled.

high

numeric value defining the high end of the input numeric range, intended when input values might not contain the entire numeric range to be re-scaled.

naValue

optional numeric value used to replace NA, usually by replacing NA with zero.

singletMethod

character value describing how to handle singlet input values, for example how to scale the number 5 by itself.

  • "mean" then it uses the average of from and to,

  • "min" uses the from value, and

  • "max" uses the to value.

...

additional parameters are ignored.

Value

numeric vector after applying the transformations.

Details

This function is intended as a quick way to scale numeric values between 0 and 1, however other ranges can be defined as needed.

NA values are ignored and will remain NA in the output. To handle NA values, use the rmNA() function, which can optionally replace NA with a fixed numeric value.

The parameters low and high are used optionally to provide a fixed range of values expected for x, which is useful for consistent scaling of x. Specifically, if x may be a vector of numeric values ranging from 0 and 100, you would define low=0 and high=100 so that x will be consistently scaled regardless what actual range is represented by x.

Note that when x contains only one value, and low and high are not defined, then x will be scaled based upon the argument singletMethod. For example, if you provide x=2 and want to scale x values to between 0 and 10... x can either be the mean value 5; the minimum value 0; or the maximum value 10.

However, if low or high are defined, then x will be scaled relative to that range.

See also

Other jam numeric functions: deg2rad(), noiseFloor(), rad2deg(), rowGroupMeans(), rowRmMadOutliers(), warpAroundZero()

Examples

# Notice the first value 1 is re-scaled to 0
normScale(1:11);
#>  [1] 0.0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1.0

# Scale values from 0 to 10
normScale(1:11, from=0, to=10);
#>  [1]  0  1  2  3  4  5  6  7  8  9 10

# Here the low value is defined as 0
normScale(1:10, low=0);
#>  [1] 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1.0

normScale(c(10,20,40,30), from=50, to=65);
#> [1] 50 55 65 60