[Qgis-user] Raster commands not found in mac

[Jesús Lopez]

Have a problem when I try to run commands in Raster menu (Qgis 3.0.0-2, MacOsX 10.11.6) :

 Processing algorithm…
AlgorithmDialog
Input parameters:
{ 'INPUT' : '/Volumes/Mapas/Ráster/0158_fot_37430_etrs89_UTM_hu29.ecw', 'BAND' : 1, 'Z_FACTOR' : 1, 'SCALE' : 1, 'AZIMUTH' : 315, 'ALTITUDE' : 45, 'COMPUTE_EDGES' : False, 'ZEVENBERGEN' : False, 'COMBINED' : False, 'MULTIDIRECTIONAL' : False, 'OPTIONS' : '', 'OUTPUT' : '/var/folders/pm/c423kdzx2ms3fblh9gcvggx40000gn/T/processing_f8d608b88ccf4e22a875f55f00d48e2a/3a81f3494608410487ed10c9bcb8696d/OUTPUT.tif' }

GDAL command:
gdaldem hillshade /Volumes/Mapas/Ráster/0158_fot_37430_etrs89_UTM_hu29.ecw /var/folders/pm/c423kdzx2ms3fblh9gcvggx40000gn/T/processing_f8d608b88ccf4e22a875f55f00d48e2a/3a81f3494608410487ed10c9bcb8696d/OUTPUT.tif -of GTiff -b 1 -z 1.0 -s 1.0 -az 315.0 -alt 45.0
GDAL command output:
/bin/sh: gdaldem: command not found 
Execution completed in 0.10 seconds
Results:
{'OUTPUT': <QgsProcessingOutputLayerDefinition {'sink':/var/folders/pm/c423kdzx2ms3fblh9gcvggx40000gn/T/processing_f8d608b88ccf4e22a875f55f00d48e2a/3a81f3494608410487ed10c9bcb8696d/OUTPUT.tif, 'createOptions': {'fileEncoding': 'System'}}>}

Loading the resulting layers
The following layers were not generated correctly.
/var/folders/pm/c423kdzx2ms3fblh9gcvggx40000gn/T/processing_f8d608b88ccf4e22a875f55f00d48e2a/3a81f3494608410487ed10c9bcb8696d/OUTPUT.tif


I follow all William instructions to install: Python first, GDAL after and last QGIS. Any idea where is the problem? This behavior is the same with other commands (change gdaldem for  /bin/sh: pct2rgb.py: command not found  or  /bin/sh: gdal_polygonize.py: command not found )

TIA
Jesus