Extract the altitude of a GPS point

[Yimi]

Buen día estimada comunidad, requiero de su invaluable apoyo para realizar lo siguiente, tengo un punto GPS capturado con geopoint, con estos datos requiero generar una nueva variable que contenga de este conjunto de datos del GPS pero únicamente los datos referentes a la altura sobre el nivel del mar.

Es posible hacer esto?, quedo altamente agradecido,

YIMI

[Kal_Lam]

I see a similar workaround here:

Pulling data from geopoint questions

But I don’t think it is supported with the current version of the pyxform cc: @Xiphware

[Yimi]

Muchas gracias estimado @kal_lam.

Quisiera preguntar, al momento de capturar un punto GPS desde ODK, se puede capturar la altura?, esto es posible??. He tomado un punto de ejemplo pero la altura se muestra en cero (0).

agradezco mucho su ayuda.

[DSimon]

Here’s another way to access geopoint data

Display GPS Precision as Note

Hello, Go with the substring solution… type geopint: Space-separated list of valid latitude (decimal degrees), longitude (decimal degrees), altitude (decimal meters) and accuracy (decimal meters) See https://getodk.github.io/xforms-spec/#data-types You might also try selected-at(${GeoPointVariable}, 3), Index here starts from 0. https://getodk.github.io/xforms-spec/#fn:selected-at

To record elevation (or accuracy) localization must be done via device’s GPS. If you manually mark a point on the map, elevation and accuracy will always be zero.

[Yimi]

Muchas gracias estimada comunidad por su apoyo, me funcionó muy bien, lo único que aún no logro resolver, es que al capturar el punto GPS, la altura en todas las pruebas me arroja cero (0).

Agradezco mucho su ayuda.

[Kal_Lam]

Thank you @DSimon for sharing the alternative approach with @Yimi. @Yimi, you could do it as outlined in the image shared below:

In the survey tab of your XLSForm:

Data entry screen as seen in Collect android app: when a GPS is captured

Data entry screen as seen in Collect android app: when the captured GPS is displayed in a note question

Reference XLSForm:

Extracting GPS Coordinates.xls (30 KB)

[DSimon]

Maybe try with another device. When locating from a Desktop PC there won’t be elevation data. But mobile phones with integrated GPS chip should provide elevation.

[Yimi]

Muchas gracias a toda la comunidad, por su invaluable apoyo.

Un abrazo desde Colombia.

[Xiphware]

…I have a GPS point captured with geopoint, with these data I need to generate a new variable that contains this set of GPS data but only the data referring to the height above it.

As described here [look under geopoint2kml section], you can extract the individual components of an acquired geopoint result - including the altitude - using the selected-at() function:

Because geopoints use a space separator, all we do is use the ODK selected-at() function to pull out the required values,…

long = selected-at(${geopoint},1)
lat = selected-at(${geopoint},0)
alt = selected-at(${geopoint},2)