function calc_sliding_sums(depth_data) {
let three_measure_sums = [];
for (let index = 0; index < depth_data.length-2; ++index) {
three_measure_sums.push(parseFloat(depth_data[index]) + parseFloat(depth_data[index+1]) + parseFloat(depth_data[index+2]))
}
return three_measure_sums
}