merged parameter description fixes from previous HTML submission

git-svn-id: https://svn.osgeo.org/grass/grass/trunk@36479 15284696-431f-4ddb-bdfa-cd5b030d7da7

vector/lidar/v.surf.bspline/main.c

@@ -86,7 +86,7 @@ int main(int argc, char *argv[])
     cross_corr_flag = G_define_flag(); {
 	cross_corr_flag->key = 'c';
 	cross_corr_flag->description =
-	    _("Find best parameters using a cross validation method");
+	    _("Find the best Tykhonov regularizing parameter using a \"leave-one-out\" cross validation method");
     }
 
     in_opt = G_define_standard_option(G_OPT_V_INPUT);
@@ -111,7 +111,7 @@ int main(int argc, char *argv[])
 	passoE_opt->required = NO;
 	passoE_opt->answer = "4";
 	passoE_opt->description =
-	    _("Interpolation spline step value in east direction");
+	    _("Length of each spline step in the east-west direction");
 	passoE_opt->guisection = _("Settings");
     }
 
@@ -121,7 +121,7 @@ int main(int argc, char *argv[])
 	passoN_opt->required = NO;
 	passoN_opt->answer = "4";
 	passoN_opt->description =
-	    _("Interpolation spline step value in north direction");
+	    _("Length of each spline step in the north-south direction");
 	passoN_opt->guisection = _("Settings");
     }
 
@@ -129,7 +129,7 @@ int main(int argc, char *argv[])
 	type->key = "type";
 	type->type = TYPE_STRING;
 	type->required = NO;
-	type->description = _("Spline type of interpolation");
+	type->description = _("Spline interpolation algorithm");
 	type->options = "bilinear,bicubic";
 	type->answer = "bilinear";
 	type->guisection = _("Settings");
@@ -139,7 +139,7 @@ int main(int argc, char *argv[])
 	lambda_f_opt->key = "lambda_i";
 	lambda_f_opt->type = TYPE_DOUBLE;
 	lambda_f_opt->required = NO;
-	lambda_f_opt->description = _("Tykhonov regularization weight");
+	lambda_f_opt->description = _("Tykhonov regularization parameter (affects smoothing)");
 	lambda_f_opt->answer = "1";
 	lambda_f_opt->guisection = _("Settings");
     }

vector/lidar/v.surf.bspline/v.surf.bspline.html

@@ -3,9 +3,9 @@
 Tykhonov regularization. The input is a 2D or 3D vector points map. Values to
 interpolate can be the z values of 3D points or the values in a user-specified
 attribue column in a 2D or 3D map. Output can be a raster or vector map.
-Optionally, a "sparse point" vector map can be input specify vector points
-output.
-<br> <br>
+Optionally, a "sparse point" vector map can be input which indicates the
+location of <b><i>output</i></b> vector points.
+<p>
 From a theoretical perspective, the interpolating procedure takes place in two
 parts: the first is an estimate of the linear coefficients of a spline function
 is derived from the observation points using a least squares regression; the
@@ -63,8 +63,8 @@ v.surf.bspline can produce a raster OR a vector output (NOT simultaneously).
 If output is a vector points map and a "<b><i>sparse=</i></b>" vector points map
 is not specified, the output vector map will contain points at the same
 locations as observation points in the input map, but the values of the output
-points are interpolated values. If a "<b><i>sparse=</i></b>" vector points map
-is specified, the output vector map will contain points at the same locations as
+points are interpolated values. If instead a "<b><i>sparse=</i></b>" vector points
+map is specified, the output vector map will contain points at the same locations as
 the sparse vector map points, and values will be those of the interpolated
 raster surface at those points.
 
@@ -73,7 +73,8 @@ A cross validation "leave-one-out" analysis is available to help to determine
 the optimal <b><i>lambda_i</i></b> value that produces an interpolation that
 best fits the original observation data. The more points used for
 cross-validation, the longer the time needed for computation. Empirical testing
-indicates a threshold of a maximum of 100 points is recommended. The
+indicates a threshold of a maximum of 100 points is recommended. Note that cross
+validation can run very slowly if more than 100 observations are used. The
 cross-validation output reports <i>mean</i> and <i>rms</i> of the residuals from
 the true point value and the estimated from the interpolation for a fixed series
 of <b><i>lambda_i</i></b> values. No vector nor raster output will be created