Hello all,

I have data that have three variables: vehicle id, speed_kmh, and Time_of_Travel.

I am seeking your help with a code that is capable of calculating the mean of all observations at each travel time (or fixed distance based on the x-axis unit) and then creating a line graph that shows the trend of the observation along with the mean of all observations. An example is shown below for speed vs distance along with my data.

I am using the following code:

xtline speed_kmh , i( vehicleid ) t( timeoftravelall ) overlay leg(off)

if possible, a code works for both cases 1- speed vs time and 2- speed vs distance.

Thank you so much.


Array Array
Vehicle ID Speed_kmh Time_of_Travel
1 80.99 0.00
1 80.99 0.50
1 80.29 1.00
1 78.92 1.50
1 76.87 2.00
1 75.50 2.50
1 74.10 3.00
1 72.67 3.50
1 70.56 4.00
1 69.17 4.50
1 67.75 5.00
1 66.27 5.50
1 64.06 6.00
1 62.59 6.50
1 61.24 7.00
1 60.02 7.50
1 58.21 8.00
1 57.03 8.50
1 55.63 9.00
1 54.03 9.50
1 51.63 10.00
1 50.06 10.50
1 48.23 11.00
1 46.13 11.50
1 42.99 12.00
1 40.90 12.50
1 39.02 13.00
1 37.38 13.50
1 34.90 14.00
1 33.25 14.50
1 31.56 15.00
1 29.84 15.50
1 27.26 16.00
1 25.53 16.50
1 23.74 17.00
1 21.87 17.50
1 19.07 18.00
1 17.21 18.50
1 15.38 19.00
1 13.58 19.50
1 10.89 20.00
1 9.10 20.50
1 8.04 21.00
1 7.72 21.50
1 7.24 22.00
1 6.92 22.50
1 6.26 23.00
1 5.28 23.50
1 3.81 24.00
1 2.83 24.50
1 2.37 25.00
1 2.41 25.50
1 2.49 26.00
1 2.54 26.50
1 2.31 27.00
1 1.81 27.50
1 1.08 28.00
1 0.59 28.50
1 0.34 29.00
1 0.34 29.50
1 0.34 30.00
2 89.11 0.00
2 89.11 0.50
2 88.32 1.00
2 86.75 1.50
2 84.43 2.00
2 82.90 2.50
2 81.78 3.00
2 81.09 3.50
2 80.08 4.00
2 79.43 4.50
2 78.11 5.00
2 76.14 5.50
2 73.21 6.00
2 71.28 6.50
2 69.13 7.00
2 66.76 7.50
2 63.26 8.00
2 60.94 8.50
2 58.31 9.00
2 55.34 9.50
2 50.88 10.00
2 47.91 10.50
2 44.91 11.00
2 41.89 11.50
2 37.37 12.00
2 34.35 12.50
2 31.19 13.00
2 27.91 13.50
2 22.98 14.00
2 19.69 14.50
2 17.45 15.00
2 16.25 15.50
2 14.46 16.00
2 13.27 16.50
2 12.21 17.00
2 11.27 17.50
2 9.86 18.00
2 8.92 18.50
2 7.94 19.00
2 6.94 19.50
2 5.43 20.00
2 4.43 20.50
2 3.63 21.00
2 3.03 21.50
2 2.14 22.00
2 1.54 22.50
2 1.11 23.00
2 0.84 23.50
2 0.47 24.00
2 0.23 24.50
2 0.12 25.00
2 0.12 25.50
2 0.12 26.00
3 86.50 0.00
3 86.50 0.50
3 85.87 1.00
3 84.65 1.50
3 82.85 2.00
3 81.67 2.50
3 80.90 3.00
3 80.54 3.50
3 80.05 4.00
3 79.74 4.50
3 78.74 5.00
3 77.04 5.50
3 74.51 6.00
3 72.85 6.50
3 70.71 7.00
3 68.09 7.50
3 64.22 8.00
3 61.65 8.50
3 58.48 9.00
3 54.67 9.50
3 48.96 10.00
3 45.16 10.50
3 41.55 11.00
3 38.13 11.50
3 33.01 12.00
3 29.59 12.50
3 26.75 13.00
3 24.49 13.50
3 21.10 14.00
3 18.84 14.50
3 16.55 15.00
3 14.24 15.50
3 10.77 16.00
3 8.46 16.50
3 7.19 17.00
3 6.96 17.50
3 6.61 18.00
3 6.38 18.50
3 5.62 19.00
3 4.33 19.50
3 2.39 20.00
3 1.10 20.50
3 0.45 21.00
3 0.45 21.50
3 0.45 22.00