Hiking elevation profile compression calculator

Calculate retained distance/elevation points and retained point count with your own figures.

Your numbers

Use the units shown. Results update as you change valid inputs.

Use retained distance/elevation points and retained point count to compare changes to your inputs. The method and limits below explain the scope.

Examples

Examples

Try the starting example

Distance km, elevation m, one measured point per line
0,0 1,1 2,0 3,2 4,0
Maximum permitted vertical interpolation error (m)
1
Retained distance/elevation points
0, 0; 2, 0; 3, 2; 4, 0
Retained point count
4
Original point count
5
Point-count reduction (%)
20
Largest vertical error at an original point (m)
1

Try another scenario

Distance km, elevation m, one measured point per line
0,0 1,1 2,0 3,2 4,0
Maximum permitted vertical interpolation error (m)
2
Retained distance/elevation points
0, 0; 4, 0
Retained point count
2
Original point count
5
Point-count reduction (%)
60
Largest vertical error at an original point (m)
2
Calculation method

Calculation method

Retained distance/elevation points

Recursively retain the interior point with the largest vertical deviation from the endpoint line whenever that deviation exceeds the entered tolerance.

Retained point count

Count retained endpoints and selected interior points.

Original point count

Count original measurements.

Point-count reduction (%)

100×(1−retained/original).

Largest vertical error at an original point (m)

Reconstruct every original distance from the compressed linear profile and report the maximum vertical deviation.

Symbols and units
a
Distance km, elevation m, one measured point per line
b
Maximum permitted vertical interpolation error (m)

Use the units shown. A list keeps the order in which you enter its values. The symbol ^ means “raised to the power of”.

Assumptions & limits

Assumptions & limits

  • An endpoint-preserving vertical-error simplifier for at most 200 measured points. Error is checked at original sample distances; this is not a guarantee about unmeasured terrain, horizontal position or navigation accuracy.
Are these inputs private?

These calculations run in your browser. A shared link contains the values you choose to share. Only questions submitted to the separate AI finder are sent to OpenAI.

Further reading

OpenStax: Euclidean geometry and trigonometric identities ↗

Background reading; this does not imply endorsement or independent review of SumFizz.

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