## Re: deafault arrow style (head length) in plots with vectors

 Re: deafault arrow style (head length) in plots with vectors From: JoanPau - 2009-05-14 22:22:37 ``` JoanPau wrote: > > > Ethan Merritt wrote: >> >> >> They are set by this routine in gadgets.c: >> >> void >> default_arrow_style(struct arrow_style_type *arrow) >> { >> static const struct lp_style_type tmp_lp_style = >> DEFAULT_LP_STYLE_TYPE; >> >> arrow->layer = 0; >> arrow->lp_properties = tmp_lp_style; >> arrow->head = 1; >> arrow->head_length = 0.0; >> arrow->head_lengthunit = first_axes; >> arrow->head_angle = 15.0; >> arrow->head_backangle = 90.0; >> arrow->head_filled = 0; >> } >> >> > > I can understand all the options but one. What does a 0.0 head_length > mean? > I thought that this would imply the same as nohead (any arrow drawn), but > obviously I was wrong. > Maybe it should be mentioned in the arrowstyle doc entry. > This example with only one vecotr may illustrate the (not self explanatory) behavior of a zero head length. The data.gnuplot has only one line of text with the coordinates of the vector: 0.0 0.0 1.0 1.0 And these are the commands (the range commands only to better visualize the vector in the plot) set xrange [-2:2] set yrange [-2:2] plot './data.gnuplot' w vectors plot './data.gnuplot' w vectors size 0,45 plot './data.gnuplot' w vectors size 0.5,45 As you can see, head is drawn with a non 0 length in the first and second case, and in the second the angle is ignored. In addition, and correct me if I misunderstand something, the head braces are not drawn in first_axes (x axis) units, since they do not change their length when the plot is resized or zoomed (for example interacting with the plot window). -- View this message in context: http://www.nabble.com/deafault-arrow-style-%28head-length%29-in-plots-with-vectors-tp23530877p23550090.html Sent from the Gnuplot - Dev mailing list archive at Nabble.com. ```

 deafault arrow style (head length) in plots with vectors From: JoanPau - 2009-05-13 22:06:23 ```Hi I would like to know what are the default values for the arrow style parameters in plots with vectors, and where are this values set in the source code. Thanks! -- View this message in context: http://www.nabble.com/deafault-arrow-style-%28head-length%29-in-plots-with-vectors-tp23530877p23530877.html Sent from the Gnuplot - Dev mailing list archive at Nabble.com. ```
 Re: deafault arrow style (head length) in plots with vectors From: Ethan Merritt - 2009-05-14 00:11:05 ```On Wednesday 13 May 2009 15:06:18 JoanPau wrote: > > Hi > > I would like to know what are the default values for the arrow style > parameters in plots with vectors, and where are this values set in the > source code. They are set by this routine in gadgets.c: void default_arrow_style(struct arrow_style_type *arrow) { static const struct lp_style_type tmp_lp_style = DEFAULT_LP_STYLE_TYPE; arrow->layer = 0; arrow->lp_properties = tmp_lp_style; arrow->head = 1; arrow->head_length = 0.0; arrow->head_lengthunit = first_axes; arrow->head_angle = 15.0; arrow->head_backangle = 90.0; arrow->head_filled = 0; } -- Ethan A Merritt ```
 Re: deafault arrow style (head length) in plots with vectors From: JoanPau - 2009-05-14 09:18:56 ``` Ethan Merritt wrote: > > > They are set by this routine in gadgets.c: > > void > default_arrow_style(struct arrow_style_type *arrow) > { > static const struct lp_style_type tmp_lp_style = > DEFAULT_LP_STYLE_TYPE; > > arrow->layer = 0; > arrow->lp_properties = tmp_lp_style; > arrow->head = 1; > arrow->head_length = 0.0; > arrow->head_lengthunit = first_axes; > arrow->head_angle = 15.0; > arrow->head_backangle = 90.0; > arrow->head_filled = 0; > } > > Thanks for the quick reply. I can understand all the options but one. What does a 0.0 head_length mean? I thought that this would imply the same as nohead (any arrow drawn), but obviously I was wrong. Maybe it should be mentioned in the arrowstyle doc entry. -- View this message in context: http://www.nabble.com/deafault-arrow-style-%28head-length%29-in-plots-with-vectors-tp23530877p23537035.html Sent from the Gnuplot - Dev mailing list archive at Nabble.com. ```
 Re: deafault arrow style (head length) in plots with vectors From: JoanPau - 2009-05-14 22:20:36 ``` JoanPau wrote: > > > Ethan Merritt wrote: >> >> >> They are set by this routine in gadgets.c: >> >> void >> default_arrow_style(struct arrow_style_type *arrow) >> { >> static const struct lp_style_type tmp_lp_style = >> DEFAULT_LP_STYLE_TYPE; >> >> arrow->layer = 0; >> arrow->lp_properties = tmp_lp_style; >> arrow->head = 1; >> arrow->head_length = 0.0; >> arrow->head_lengthunit = first_axes; >> arrow->head_angle = 15.0; >> arrow->head_backangle = 90.0; >> arrow->head_filled = 0; >> } >> >> > > I can understand all the options but one. What does a 0.0 head_length > mean? > I thought that this would imply the same as nohead (any arrow drawn), but > obviously I was wrong. > Maybe it should be mentioned in the arrowstyle doc entry. > This example with only one vecotr may illustrate the (not self explanatory) behavior of a zero head length. The data.gnuplot has only one line of text with the coordinates of the vector: File data.gnuplot wrote: > > 0.0 0.0 1.0 1.0 > And these are the commands (the range commands only to better visualize the vector in the plot) set xrange [-2:2] set yrange [-2:2] plot './data.gnuplot' w vectors plot './data.gnuplot' w vectors size 0,45 plot './data.gnuplot' w vectors size 0.5,45 As you can see, head is drawn with a non 0 length in the first and second case, and in the second the angle is ignored. In addition, and correct me if I misunderstand something, the head braces are not drawn in first_axes (x axis) units, since they do not change their length when the plot is resized or zoomed (for example interacting with the plot window). -- View this message in context: http://www.nabble.com/deafault-arrow-style-%28head-length%29-in-plots-with-vectors-tp23530877p23550072.html Sent from the Gnuplot - Dev mailing list archive at Nabble.com. ```
 Re: deafault arrow style (head length) in plots with vectors From: JoanPau - 2009-05-14 22:22:37 ``` JoanPau wrote: > > > Ethan Merritt wrote: >> >> >> They are set by this routine in gadgets.c: >> >> void >> default_arrow_style(struct arrow_style_type *arrow) >> { >> static const struct lp_style_type tmp_lp_style = >> DEFAULT_LP_STYLE_TYPE; >> >> arrow->layer = 0; >> arrow->lp_properties = tmp_lp_style; >> arrow->head = 1; >> arrow->head_length = 0.0; >> arrow->head_lengthunit = first_axes; >> arrow->head_angle = 15.0; >> arrow->head_backangle = 90.0; >> arrow->head_filled = 0; >> } >> >> > > I can understand all the options but one. What does a 0.0 head_length > mean? > I thought that this would imply the same as nohead (any arrow drawn), but > obviously I was wrong. > Maybe it should be mentioned in the arrowstyle doc entry. > This example with only one vecotr may illustrate the (not self explanatory) behavior of a zero head length. The data.gnuplot has only one line of text with the coordinates of the vector: 0.0 0.0 1.0 1.0 And these are the commands (the range commands only to better visualize the vector in the plot) set xrange [-2:2] set yrange [-2:2] plot './data.gnuplot' w vectors plot './data.gnuplot' w vectors size 0,45 plot './data.gnuplot' w vectors size 0.5,45 As you can see, head is drawn with a non 0 length in the first and second case, and in the second the angle is ignored. In addition, and correct me if I misunderstand something, the head braces are not drawn in first_axes (x axis) units, since they do not change their length when the plot is resized or zoomed (for example interacting with the plot window). -- View this message in context: http://www.nabble.com/deafault-arrow-style-%28head-length%29-in-plots-with-vectors-tp23530877p23550090.html Sent from the Gnuplot - Dev mailing list archive at Nabble.com. ```