New functions: calculate daily min/max values

Calculate the minimum and maximum of observation values for a daily
interval

public/js/src_modules/aggregate.mjs

@@ -5,6 +5,28 @@ import {
   extractObservationValuesWithinMonthInterval,
 } from "./aggregateHelpers.mjs";
 
+/**
+ * Calculate the minimum observation values that fall within a time interval delimited by a start date and end date
+ * @param {Array} obsValuesForDaysIntervalArr An array of observation values that fall within our time interval
+ * @returns {Number} A floating-point number representing the minimum of observation values
+ */
+const calculateMinimumObservationValuesWithinDatesInterval = function (
+  obsValuesForDaysIntervalArr
+) {
+  return Math.min(...obsValuesForDaysIntervalArr);
+};
+
+/**
+ * Calculate the maximum observation values that fall within a time interval delimited by a start date and end date
+ * @param {Array} obsValuesForDaysIntervalArr An array of observation values that fall within our time interval
+ * @returns {Number} A floating-point number representing the maximum of observation values
+ */
+const calculateMaximumObservationValuesWithinDatesInterval = function (
+  obsValuesForDaysIntervalArr
+) {
+  return Math.max(...obsValuesForDaysIntervalArr);
+};
+
 /**
  * Calculate the sum of observation values that fall within a time interval delimited by a start date and end date
  * @param {Array} obsValuesForDaysIntervalArr An array of observation values that fall within our time interval