Linear Detrend

Takes a time series dataset, fits a linear trend to the data, and returns the dataset with the linear trend subtracted out.

Table of Contents

• Inputs
• Outputs
• Algorithm Console

Inputs

JSON Format

You must set either uniformlySpaced or variablySpaced json values, but not both.

{
    "uniformlySpaced": Double[],
    "variablySpaced": Double[][]
}

uniformly spaced

{"uniformlySpaced": [1,2,3,4,3,4,6,7,5,4,2,1,1]}

variably spaced

{"variablySpaced": [[1,2,3,4,5,6,6.5,7,8.5,9,10,11,12],[1,2,3,4,3,4,6,7,5,4,2,1,1]]}

• uniformlySpaced - (pick one) - dataset is a 1D array filled with uniformly spaced y coordinates, assumes all datapoints are uniformly spaced in the X axis (IE: input[y] where dx(1) = dx(n))
• variablySpaced - (pick one) - Dataset is a 2D array where with the first axis X and second Y (IE: input[X][Y]). both arrays must be the same size.

Array Format

[
    first: Double[],
    second: Double[]
]
    

uniformly spaced

[[1,2,3,4,3,4,6,7,5,4,2,1,1]]

variably spaced

[[1,2,4,8,16,32,64,128,256,512],[1,2,3,4,3,4,6,7,5,4]]

• first - (required) - if second is not defined, this field defines the dataset's Y axis, and assumes that all datapoints are uniformly spaced in the X axis (IE: dx(1) = dx(n))
• second - (optional) - if defined, first becomes the X axis coordinates for each datapoint, and second becomes the Y axis for each datapoint.

Outputs

This algorithm output's in the same format it recieved input: if you passed it JSON data it returns JSON data, if you passed it array data it returns array data, etc.

JSON Format

{"output": [
  -2.373626373626374,
  -1.3626373626373631,
  -0.3516483516483522,
  0.6593406593406588,
  -0.3296703296703303,
  0.6813186813186807,
  2.6923076923076916,
  3.7032967032967026,
  1.7142857142857135,
  0.7252747252747245,
  -1.2637362637362641,
  -2.252747252747253,
  -2.241758241758242
]}

• output - The input datset with any linear trend removed.

Array Format

[
  -2.373626373626374,
  -1.3626373626373631,
  -0.3516483516483522,
  0.6593406593406588,
  -0.3296703296703303,
  0.6813186813186807,
  2.6923076923076916,
  3.7032967032967026,
  1.7142857142857135,
  0.7252747252747245,
  -1.2637362637362641,
  -2.252747252747253,
  -2.241758241758242
]

• output - The input datset with any linear trend removed.