How can I extract increasing consecutive values? - iterator

Question

I have a sample array of objects...
const entries = [
{
userID: 1,
date: '2019/06/15',
numSteps: 3577,
minutesActive: 140,
flightsOfStairs: 16
},
{
userID: 1,
date: '2019/06/16',
numSteps: 6637,
minutesActive: 175,
flightsOfStairs: 36
},
{
userID: 1,
date: '2019/06/17',
numSteps: 14329,
minutesActive: 168,
flightsOfStairs: 18
},
{
userID: 1,
date: '2019/06/18',
numSteps: 4419,
minutesActive: 165,
flightsOfStairs: 33
},
{
userID: 1,
date: '2019/06/19',
numSteps: 8429,
minutesActive: 275,
flightsOfStairs: 2
},
{
userID: 1,
date: '2019/06/20',
numSteps: 14478,
minutesActive: 140,
flightsOfStairs: 12
},
{
userID: 1,
date: '2019/06/21',
numSteps: 6760,
minutesActive: 135,
flightsOfStairs: 6
},
{
userID: 1,
date: '2019/06/22',
numSteps: 10289,
minutesActive: 119,
flightsOfStairs: 6
},
{
userID: 1,
date: '2019/06/23',
numSteps: 8213,
minutesActive: 122,
flightsOfStairs: 27
},
{
userID: 1,
date: '2019/06/24',
numSteps: 11654,
minutesActive: 270,
flightsOfStairs: 19
}
]
I am trying to find instances of increasing numSteps through a for loop, so if there are consecutive days of increasing steps, those days get pushed into a new array. This is my loop...
let dates = []
for (var i = 0; i < this.entries.length - 1; i++) {
if (this.entries[i].numSteps < this.entries[i + 1].numSteps) {
dates.push(this.entries[i])
}
}
I am very close to getting this to work, but can't figure out how to push the final value before the condition is met. I should be getting the first three index pushed into the new array, but am only getting two. I see why this is happening, because by the time I hit the third index, the condition in my loop is no longer true. I am just not sure how I can push the indexes that meet the condition and the one directly after that. Any suggestions? Thanks!

Answer 1

You need to make the for loop cover the full range, then enhance the if statement to compare with both next and previous.
let len = this.entries.length;
for (var i = 0; i < len ; i++) {
if ((i < len - 1 && this.entries[i].numSteps < this.entries[i + 1].numSteps)
|| (i > 0 && this.entries[i - 1].numSteps < this.entries[i].numSteps)) {
dates.push(this.entries[i])
}
}