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<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>Dear people,<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span lang=EN-GB style='font-size:
10.0pt;font-family:Arial'>I’m interpolating some data by means of v.surf.idw.
I loaded data in a database using v.in.ascii and create a vector layer. Here is
an example of five loaded fields of one row. X and y coordinates are in the two
first columns. Other fields are data to interpolate. But some stations missed some
data. So, the imported database contains blank values whenever data is not
available. This row has blank (no data or null) values in data2:<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span lang=EN-GB style='font-size:
10.0pt;font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span lang=EN-GB style='font-size:
10.0pt;font-family:Arial'>X;y;data1;data2;data3<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span lang=EN-GB style='font-size:
10.0pt;font-family:Arial'>623649;4784544;2.3;;1.98<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span lang=EN-GB style='font-size:
10.0pt;font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span lang=EN-GB style='font-size:
10.0pt;font-family:Arial'>I have no problems using data1 and data3 in
v.surf.idw procedure. The problem appears when trying to use data2. It seems
that the interpolation procedure takes “<st1:metricconverter
ProductID="0.0”" w:st="on">0.0”</st1:metricconverter> value when it
should not consider anything. How can I manage null (no data) in v.surf.idw?<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span lang=EN-GB style='font-size:
10.0pt;font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span lang=EN-GB style='font-size:
10.0pt;font-family:Arial'>Thanks in advance<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span lang=EN-GB style='font-size:
10.0pt;font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal><st1:PersonName ProductID="Javier Álvarez Rodríguez" w:st="on"><font
size=2 face="Times New Roman"><span style='font-size:10.0pt'>Javier Álvarez
Rodríguez</span></font></st1:PersonName><o:p></o:p></p>
<p class=MsoNormal><font size=2 face="Times New Roman"><span style='font-size:
10.0pt'>Área de Hidrología del Centro de Estudios Hidrográficos del CEDEX </span></font><o:p></o:p></p>
<p class=MsoNormal><font size=2 face="Times New Roman"><span style='font-size:
10.0pt'>Paseo Bajo de la Virgen del Puerto, 3</span></font><o:p></o:p></p>
<p class=MsoNormal><font size=2 face="Times New Roman"><span style='font-size:
10.0pt'>Madrid 28007. España</span></font><o:p></o:p></p>
<p class=MsoNormal><font size=2 face="Times New Roman"><span style='font-size:
10.0pt'>+34 91 335 79 38</span></font><o:p></o:p></p>
<p class=MsoNormal><font size=2 face="Times New Roman"><span style='font-size:
10.0pt'>+34 91 335 79 22</span></font><o:p></o:p></p>
<p class=MsoNormal><st1:PersonName w:st="on"><font size=2 face="Times New Roman"><span
style='font-size:10.0pt'>javier.alvarez@cedex.es</span></font></st1:PersonName><o:p></o:p></p>
<p class=MsoNormal><font size=2 face="Times New Roman"><span style='font-size:
11.0pt'> </span><o:p></o:p></font></p>
<p class=MsoNormal><font size=2 face="Times New Roman"><o:p> </o:p></font></p>
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