I am trying to get NDVI and NDMI statistics for every observation within a time range (I wanted to include CLM and SCL for filtering cloudy and water pixels)

Apps / Services Python SDK
1

Here is the evalscript i am trying to run, but it throws bad http error: 400.

calculate_ndvi_stats= """

//VERSION=3
function setup() {
  return {
    input: [{
      bands: [
        "B04",
        "B08",
        "B11",
        "SCL",
        "CLM",
        "dataMask"
      ]
    }],
    output: [
      {
        id: "indices",
        bands: 3
      },
      {
        id: "dataMask",
        bands: 1
      }]
  }
}

function evaluatePixel(samples) {
    let ndvi = (samples.B08 - samples.B04)/(samples.B08 + samples.B04)
    
    var validNDVIMask = 1
    if (samples.B04 + samples.B08 == 0 ){ //check if all the bands are 0
        validNDVIMask = 0
    }

    lef ndmi =(samples.B08 - samples.B11) / (samples.08 + samples.B11)

    }

    var validNDMIMask = 1
    if (samples.B08 + samples.B11 == 0 ){ //check if all the bands are 0
        validNDMIMask = 0
    }
    var noWaterMask = 1
    if (samples.SCL == 6 ){ //check if pixels are classified as water using SCL band
        noWaterMask = 0
    }
    // masking cloudy pixels
    let combinedMask = samples.dataMask
    if (samples.CLM > 0) {
        combinedMask = 0;
    }

    return {
        indices: [ndvi,ndmi],
        dataMask: [samples.dataMask * validNDVIMask * noWaterMask * combinedMask]  //if even one of the three exclusion criteria is 0, the pixel will be excluded
    }
}
"""

It will be great if I can get help to run this. I am looking to get a NDVI time series for a specific area of interest

2

In the setup, you specify that “indices” output will have 3 bands, but you only return 2: ndvi and ndmi.

There also seems to be a syntax error in your script - an extra “}” after the ndmi.

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