Scilab : add legend for surface plot - graph

I would like to add a legend to a surface plot.
I have tried, doing like this :
X=[0:0.3:2*%pi]; //example data
[x,y]=ndgrid(X,X);
z1=sin(X')*cos(X);
z2=z1/2;
z3=z1/3;
figure=scf();
surf(x,y,z1);
surf(x,y,z2);
surf(x,y,z3);
axes=figure.children(1);
axes.children(1).foreground=color(0,0,0);
axes.children(2).foreground=color(0,0,0);
axes.children(3).foreground=color(255,0,0);
axes.children(1).color_flag=0;
axes.children(2).color_flag=0;
axes.children(3).color_flag=0;
axes.children(1).color_mode=color(0,255,0);
axes.children(2).color_mode=color(0,0,255);
axes.children(3).color_mode=0;
legend(['z1','z1 divided by 2','z1 divided by 3'],opt=2,font_size=2);
I get the following error message:
!--error 10000
legend : Neither handle of type 'Polyline' can be found.
If it's not possible to do this with the basic version of Scilab, could you please advise to me some libraries Scilab permitting to do this.
Thanks for your help.

Legend not possible for surface plots
Legends is only for plot2dx graphs as stated in the documentation of legend properties:
This entity defines the parameters for legends drawn below plot2dx
graphs or created by the captions function.
Alternatives
You could simply add a title using xtitle
xtitle('z1,z1 div by2, z2 div by 3');
You could draw a box using uicontrol and style it using uicontrol_properties:
fig = gcf();
uicontrol(fig, "style", "text", ...
"string", "<html>z1<br>z1/2<br>z1/3</html>", ...
"position",[100 100 100 100], ...
"fontsize",15);

Related

Legend Function Doesn't Make a Legend Appear

I am trying to add a legend to my R plot that has five lines which I built with the following code:
predictors=c(1,3,5,7,10,13)
meanvec25=c(23.642465, 14.590552, 11.480690, 10.919103, 9.365745, 10.265116)
meanvec100=c(22.668256, 12.220893, 10.598733, 9.768388, 9.710492, 10.139874)
meanvec500=c(21.864226, 12.290780, 9.879924, 9.598233, 9.856007, 9.629011)
meanvec2000=c(22.072814, 11.658274, 10.208657, 9.789607, 9.720389, 9.781965)
meanvec5000=c(22.006622, 11.535754, 10.172841, 9.664394, 9.722084, 9.814400)
plot(predictors,meanvec25,col="red",type="l")
lines(predictors,meanvec100,col="blue",type="l")
lines(predictors,meanvec500,col="green",type="l")
lines(predictors,meanvec2000,col="purple",type="l")
lines(predictors,meanvec5000,col="orange",type="l")
Then I typed this line to add a legend:
legend(1,95,legend=c("25 Trees","100 Trees","500 Trees","2000 Trees","5000 Trees"),col=c("red", "blue","green","purple","orange"), lty=c(1,1,1,1,1), cex=0.8)
Nothing is added to my graph, but no error messages appear either. I tried fiddling with the location numbers at the beginning of the function, but it doesn't seem to help. Why won't the legend appear?
Thanks!

In Observable Plot, how to sort/order the stack from a bin() transform?

I'm working on a stacked bar chart in Observable's new Plot library. It's not too bad coming from Vega and D3, but I cannot find or figure how to order the resulting stacked bars from the Plot.binX() I'm using.
My actual mark looks something like this today:
Plot.rectY(hourlyUsageData, Plot.binX({
y: "sum",
title: bin => bin[0].Name
}, {
x: d => d3.timeHour.count(d3.timeDay(d.DateTime), d.DateTime),
y: d => d.kWh,
thresholds: 24,
fill: "Name",
//order: "sum",
//reverse: true
}))
Plot.binX() does just fine, resulting in a chart in which the stack is ordered according to the input ordering.
I'd like the stack to be ordered based on a sum, and in fact if I add the Plot.stack option for order (see commented line above), I can order by sum:
Close! Now I just need to reverse the order. I hypothesize that, since I can use the order option, perhaps I can also use the reverse option (see commented line above). That doesn't seem to work.
My second hypothesis is that, since these transforms are supposed to be "composable", that I should be able to combine my binX with a stackY, but I cannot find an example of such a composition. I've tried Plot.stackY(Plot.binX({...}, { ... order:"sum", reverse:true }), and similar variations, but they don't seem to work either.
In summary, I'd love to know how to control the order of the stacks in my stacked bar chart while also using binX. Thanks!
Thank you. It seems that there is a bug and the {order} option is consumed for nothing by the bin transform. We'll try to fix this. In the meantime you can add it "outside" the bin transform like so:
Plot.rectY(data,
Plot.stackY({
...Plot.binX(
{ y: "count" },
{ x: "body_mass", fill: "species", order: "sum" }
),
reverse: true
})
).plot()
Pull-request to solve this issue: https://github.com/observablehq/plot/pull/439

Vectors plot of electric field

I trying to plot vectors of electric field in scilab. But it always error :
champ: Wrong size for input arguments: Incompatible sizes.
the code:
epsilon0=1e-9/(36*%pi);
q=3e-9;
p=[-1,0,0];
x=-2:0.2:2;
y=-2:0.2:2;
[px,py]=meshgrid(x,y);
for m=1:length(x),
for n=1:length(y),
xp=px(m,n);
yp=py(m,n);
vektorr1x=xp-p(1);
vektorr1y=yp-p(3);
r1=sqrt(vektorr1x^2+vektorr1z^2);
if r1~=0 then
ar1x=vektorr1x/r1;
ar1y=vektorr1y/r1;
E1x=q*ar1x/(4*%pi*epsilon0*r1^2);
E1y=q*ar1y/(4*%pi*epsilon0*r1^2);
else
E1x=0;
E1y=0;
end,
end,
end,
pl=champ(px,py,E1x,E1y,[-2,-1,2,-1]);
You don't have to use loops, the following script does what you want:
epsilon0=1e-9/(36*%pi);
q=3e-9;
p=[-1,0,0];
x=-2:0.2:2;
y=-2:0.2:2;
[px,py]=ndgrid(x,y);
vektorr1x=px-p(1);
vektorr1y=py-p(3);
r1=sqrt(vektorr1x.^2+vektorr1y.^2);
ar1x=vektorr1x./r1;
ar1y=vektorr1y./r1;
E1x=q*ar1x./(4*%pi*epsilon0*r1.^2);
E1y=q*ar1y./(4*%pi*epsilon0*r1.^2);
E1x(r1==0)=0;
E1y(r1==0)=0;
clf
champ(x,y,E1x,E1y,[-2,-1,2,-1]);
To plot fields don't use meshgrid to sample the domain use ngrid instead. Moreover, don't forget to use dot-prefixed operators.

Octave: Change color in drawArrow

I found this answer
[Octave : How to change line color and width in drawRect
how to change the color in drawRect.
When I try the same for drawArrow, I get:
h=drawArrow(0,0,3,1,1,1,1,1);
h =
scalar structure containing the fields:
body = -12.469
head = -11.925
set(h,'color','r');
error: octave_base_value::array_value():
wrong type argument 'scalar struct'
error: set: H must be a graphics handle
What I am doing wrong here? For me it looks the same.
Thanks
Karl
You really should mention that you are using the octave-forge geometry package. drawArrow returns a struct with handles for the arrow body and head (as shown by your code) so you can and have to set them separately:
pkg load geometry
h = drawArrow (0,0,3,1,1,1,1,1);
set (h.body, "color", "r")
set (h.head, "facecolor", get(h.body, "color"))
You can also set a border around the head with "edgecolor"

visjs graph2d showMinorLines example

I want to hide the horizontal major/minor lines that appear on Graph2D Y-axis values of a scatter plot/timeline.
I have tried to make use of showMinorLines and showMajorLines without much success. The syntax am using is:
graph2d.setOptions({showMinorLines: false})
However, it generates an error that states:
Unknown option detected: "showMinorLines". Did you mean
"showMinorLabels"?
Problem value found at: options = { showMinorLines }
vis.js:23607 Errors have been found in the supplied options object.
Any help would be much appreciated?
Update: Attaching image.
Thanks for bringing this up. This is an fault in the documentation: in v4, this option has been renamed to get a more consistent API. You now have the following four related options:
{
showMinorLabels: true | false, // minor labels and lines on horizontal axis
showMajorLabels: true | false, // major labels and lines on horizontal axis
dataAxis: {
showMinorLabels: true | false, // minor labels and lines on vertical axis
showMajorLabels: true | false, // major labels and lines on vertical axis
}
}
We will fix the docs, sorry for the inconvenience.

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