score:1

You should define your x-axis as a time cartesian axis and provide the data as individual points, where each element has a `t` and an `y` property (also take a look at this answer). Using `Array.map()`, this can be done as follows:

``````data['Julian dates']
.map((d, i) => ({ t: julianIntToDate(d), y: data['ndvi values'][i] }))
``````

Note that I use the `julianIntToDate` function provided by Stephane BOISSEAU in this answer to convert the Julian dates into regular dates.

Please take a look at the runnable code below and see how it works. While this is plain JavaScript, it should be easy to make it also work with `react-chartjs-2`.

``````const data = {
'ndvi values': [0.1158, 0.1975, 0.1913, 0.2137, 0.1603, 0.13, 0.246, 0.249, 0.1955, 0.124, 0.1854, 0.2721, 0.2095, 0.1357, 0.2444],
'Julian dates': [2458208.0, 2458386.0, 2458476.0, 2458566.0, 2458653.0, 2458746.0, 2458836.0, 2458921.0, 2459026.0, 2459111.0, 2458391.0, 2458476.0, 2458566.0, 2458746.0, 2458836.0]
};

// convert a Julian number to a Gregorian Date (S.Boisseau / BubblingApp.com / 2014)
function julianIntToDate(n) {
var a = n + 32044;
var b = Math.floor(((4*a) + 3)/146097);
var c = a - Math.floor((146097*b)/4);
var d = Math.floor(((4*c) + 3)/1461);
var e = c - Math.floor((1461 * d)/4);
var f = Math.floor(((5*e) + 2)/153);

var D = e + 1 - Math.floor(((153*f) + 2)/5);
var M = f + 3 - 12 - Math.round(f/10);
var Y = (100*b) + d - 4800 + Math.floor(f/10);
return new Date(Y,M,D);
}

new Chart('myChart', {
type: 'scatter',
data: {
datasets: [{
label: 'ndvi values',
data: data['Julian dates'].map((d, i) => ({ t: julianIntToDate(d), y: data['ndvi values'][i] })),
borderColor: 'blue',
}]
},
options: {
scales: {
yAxes: [{
ticks: {
beginAtZero: true
}
}],
xAxes: [{
type: 'time',
time: {
unit: 'month',
displayFormats: {
month: 'YYYY/M'
},
tooltipFormat: 'YYYY/M/D'
}
}]
}
}
});``````
``````<script src="https://cdnjs.cloudflare.com/ajax/libs/Chart.js/2.9.4/Chart.bundle.min.js"></script>
<canvas id="myChart" height="90"></canvas>``````

score:0

Try this library: Chart.Scatter/