I want to fit a lsline (h=lsline) to a scatterplot in MATLAB. The data is in the xrange between [-2.5 2.5] and I display them with and xlim of [-3 3]. I want to show the lsline only in the range between [-2.9 2.9].
However, when I add h.XData=[-2.9 2.9] the slope of the line changes. Does that make sense to anyone? There is no datapoint between 2.5 and 3 and I expected to only see differences in the length of the line?
Simply change the axis limits after plotting the line:
x = -2.5:.125:2.5;
y = .5 .* x + randn(1,numel(x))*.2;
scatter(x,y);
xlim([-2.9 2.9])
lsline;
xlim([-3 3])
ylim([-1.6 2])
I'm trying to display a discrete plot with values on the x-axis that are not equally space but I want them to appear equally spaced. I would like a stem plot with the first stick not on the y-axis, and I'd also like to have an horizontal dashed line at y=1.
So far here is what I tried.
x = [10 50 150 3000];
y = [.6 .754 .853 .954];
xv = [1 2 3 4];
stem(xv,y);
set(gca,'XTickLabel',x);
Unfortunately, this is not what I expected. The value on the x-axis are not right and the sticks start on the y-axis and end on the figure edge.
How can I fix this?
EDIT: I initially forgot the horizontal dashed line. Added this.
You just need two tiny additions:
x = [10 50 150 3000];
y = [.6 .754 .853 .954];
xv = [1 2 3 4];
stem(xv, y);
xlim([min(xv)-1 max(xv)+1]); % <--
set(gca, 'xtick', xv); % <--
set(gca, 'xticklabel', x);
You (also) need to explicitly set the xtick option, so that only these ticks are drawn, and no other.
With xlim, you can manipulate the x-axis limits. (Left and right limit might be modified to your needs.)
To add the horizontal dashed line, just add the following at the end:
hold on;
plot([min(xv)-1 max(xv)+1], [1 1], 'k--');
hold off;
(Start and end points of the line might be modified to your needs.)
From Matlab R2018b on, you could also use yline.
The output then looks like this:
When you have a sequence of values that you want to plot equally spaced without any special treatment to what each value actually is, you're essentially defining a set of categories.
MATLAB is good at handling these nicely without any extra trickery to lay them out uniformly on your axes if you declare the values explicitly as categorical.
All you need, therefore, is:
x = [10 50 150 3000];
y = [.6 .754 .853 .954];
stem(categorical(x),y);
yline(1,'--');
ylim([0 1.5]) % Make some space on the y-axis so the horizontal line doesn't sit on the top edge
I want to create a small gap between begining of the bar plot and xaxis when plotting negative and poistive values.
Given:
barData = [1 2 3; 2 2 2];
bar(barData,'stacked')
hold on
bar(barData*-1, 'stacked')
returns usual stacked bar plot which looks like this (no spaces):
and I would like to have a space between xaxis and the begining of the yaxis something as in this example (in this case its not stacked bar and only positve values).
You mean like this?
barData = [1 2 3; 2 2 2];
bar(barData,'stacked','BarWidth',0.65);
hold on;
bar(barData*-1,'stacked','BarWidth',0.65);
hold off;
y_lim = get(gca,'YLim') + [-1 1];
set(gca,'YLim',y_lim);
I have a tricky question, which I think cannot be simply answered.
I have a large data table and want to save bar charts for each 2 corresponding mean values. I already did that with "for loop", but I cannot set different colors to my bars and cannot set proper spaces between bars and axes.
That's the simplest example:
k = [2 5]
bar(k)
Matlab thinks about those data [2 5] as about one "group" and it does not give a possibility of changing color for only one bar.
Of course, when we have different "groups", colors are changeable.
y = bar([1 2 3; 4 5 6]);
y(2).FaceColor = 'red';
But what about my example? I need only two bars, and I need to color them differently. Also, I want to set a small space between each bar and the axes (and again with two bars it is not that simple, and I cannot use "bar width" because that doesn't give me what I really want).
Does anyone know how to get around this?
Thanks for any reply!
Mary
A good trick could be add zero column for each group:
k = [2 5;0 0];
bar(k,'grouped')
UPDATE
Another solution to have different color could be using location in bar:
k = [2 5];
figure(1);
hold on;
h=bar(1,k(1));
set(h,'FaceColor','k');
h=bar(2,k(2));
set(h,'FaceColor','b');
hold off
As far as I know, this requires the use of a custom bar plot, since Matlab's barplots use dynamic colormaps. Personally, I like the GRAMM toolbox for all these customizations: [GRAMM on file-exchange] [GRAMM on github].
Here's an example:
x = [1 2];
y = [1 1.5];
c = x;
custom_map = ...
[1 0.3673 0.4132;
0 0.7375 0.8344];
clear g
g(1,1)=gramm('x',x,'y',y,'color',c);
g(1,1).geom_bar('width',0.2);
g(1,1).set_title('Width = 0.2');
g(1,2)=gramm('x',x,'y',y,'color',c);
g(1,2).geom_bar('width',0.8);
g(1,2).set_title('Width = 0.8');
g.set_names('y','','x','');
g.set_color_options('map',custom_map);
g.axe_property('YTick',[],'LineWidth',1,'YColor',[1 1 1],'XLim',[0.5 2.5],'XTick',[1 2])
figure('Position',[100 100 600 300]);
g.draw();
The histogram function is one option that will easily handle the spacing and x-axis labeling, but you'll have to plot each bar separately to independently control the colors:
k = [2 5];
histogram('Categories', {'ONE'}, 'BinCounts', k(1), 'BarWidth', 0.8, ...
'FaceAlpha', 1, 'FaceColor', [0 0.4470 0.7410]);
hold on;
histogram('Categories', {'TWO'}, 'BinCounts', k(2), 'BarWidth', 0.8, ...
'FaceAlpha', 1, 'FaceColor', [0.8500 0.3250 0.0980]);
Here is an option to workaround this. You can use diag(k) to create a 2*2 matrix with all zeros except the main diagonal that will be with your values, and Matlab will read it as 2 different groups. Then you change the Xdata of the 'dummy' bars (which you don't see but take some space on the x axis to nan so Matlab will ignore it.
k = [2 5];
b = bar(diag(k));
set(b,{'XData'},{[1 nan],[nan 1]}); % remove the group you don't want
set(gca,{'xticklabel','XTick'},{{'ONE','TWO'},[0.85 1.15]});
b(2).FaceColor = 'r'; % choose a different color
The result:
And if you want to generalize this to more groups (here it's 5):
k = 1:5;
data = diag(k);
xdata = eye(numel(k))./eye(numel(k)); % a martix of nan with 1 on the main diagonal
b = bar(diag(k));
% remove all data except one bin in all groups:
set(b,{'XData'},mat2cell(xdata,ones(size(data,1),1),size(data,2)))
X = xlim; 5 get x-axis limits
w = (1-X(1))/(numel(k)/2); % calculate the width of one bin
set(gca,'XTick',X(1)+w/2:w:X(2)) % set the X ticks to the center of the bins
set(gca,'xticklabel',{'ONE','TWO','THREE','FOUR','FIVE'}); % set the labels
set(b,{'FaceColor'},mat2cell(lines(numel(k)),ones(size(data,1),1),3)); % set the colors
and you get:
And finally, if you want them to 'hover' a little above the x-axis, you can add the following lines:
b(1).BaseLine.Color = 'none'; % remove the base line
ylim([-0.1 max(k(:))]) % shift the bars up a little
and get:
I only want
the x-axis to display 1 2 3 4 5 6
the y-axis to display 0 20 40 60 80 100
change the numbers font size to 14
I've tried by setting different axis property (ref. to the commented lines of code in the script below) however none of them affect the graph.
%Code to generate the diceSum
DiceSum = myDiceRoller(1,500);
figure(1)
%Create the histogram
hist(DiceSum,NDice*6)
%Label the axes
xlabel('Value of Roll','FontSize',16)
ylabel('Number of Times Rolled','FontSize',16)
%set(gca,'X','FontSize',14)
%set(gca,'YTickLabel',{'0' ;'100'})
%set('xtick','FontSize',14)
%set('Xlim',[0,6], 'Ylim',[0 ,100])
%set('xtick',[0:1:6],'ytick',[0:20:100])
%set(gca,'XLim',[0 6])
%set(gca,'XTick',[0 1 2 3 4 5 6])
%set(gca,'XTickLabel',str2mat{'0','1','2','3','4','5','6')
%xlim([0 6])
This is a separate function I'm using to create the data and the histogram
function [DiceSum] = myDiceRoller(NDice,NRolls)
DiceSum = zeros(1,NRolls);%
for i = 1:NRolls;% on roll 1...roll 2
for j = 1:NDice;% on roll 1 , roll #s of die
n = ceil(rand(1)*6);
DiceSum(1,i) = DiceSum(1,i) + n;
end
hist(DiceSum,NDice*6)
xlabel('Value of Roll')
ylabel('Number of Times Rolled')
end
To have the x-axis displaying 1 2 3 4 5 6 you have to two possibilities:
to change the way you call the hist function as follows:
% hist(DiceSum,1:NDice*6)
hist(DiceSum,1:6)
this because in the call to hist with 2 parameters, the second one should be a vector, in that case, hist returns the distribution of Y among length(x) bins with centers specified by x (being x the second parameter) - R2012b hist help
to directly set the x-axis xtick as follows:
set(gca,'xtick',[0:6])
To have the y-axis displaying 0 20 40 60 80 100 you have to set the y-axis ytick as follows:
set(gca,'ytick',[0:20:100])
To change the x and y axis tick font size to 14 you have to set the axis fontsize as follows:
set(gca,'FontSize',14)
Hope this helps.