I need to plot a histogram

I tried to plot it with the excel, but excel is giving size range as the same size columns. Columns width is not supposed to be the same. So, I changed the program and decided to plot this histogram on the Matlab.

Can you help me to plot that histogram?

Size Interval (um)
0-0.2
0.2-0.4
0.4-0.6
0.6-0.8
0.8-1.0
1.0-1.2
1.2-1.4
1.4-1.6
1.6-1.8
1.8-2.1
2.1-2.7
2.7-3.6
3.6-5.1

and

Number of particle in interval per cm-3 of air
10
80
132
142
138
112
75
65
52
65
62
32
35

Answer 1

[Star Strider]

This may do what you want.

The Code —

edges = [0 : 0.2 : 1.8, 2.1, 2.7, 3.6, 5.1];
vals = [10    80   132   142   138   112    75    65    52    65    62    32    35];

V1 = [vals' diff(edges')];
V1L = [0; cumsum(V1(:,2))];                                             % Cumulative Lengths

figure
AxH = axes('NextPlot','add');
for k1 = 1:size(V1,1)
    patch([0 1 1 0]*V1(k1,2)+V1L(k1),[0 0 1 1]*V1(k1,1), rand(1,3), 'LineWidth',0.1)
end
hold off
axis([min(edges)  max(edges)    0  max(ylim)])
set(gca, 'XTick',V1L, 'FontSize',8)

I chose random colours. Experiment to get the result you want.

The Plot —

[leonidas86]

Hello Star Strider,

very nice solution. Is there a way to do this without the for loop?

[Star Strider]

Thank you.

It might be possible with arrayfun (that contains implied loops). The for loop is easier, and likely more efficient.

[Peyman Mostafaei]

In addition to this answer, there is another way which uses the command bar instead of patch.

You have to know that the default width in the bar command is 1. All you have to do is to create your plot for each element of data separately based on this fact through a for loop.

edges = [0 : 0.2 : 1.8, 2.1, 2.7, 3.6, 5.1];
vals = [10    80   132   142   138   112    75    65    52    65    62    32    35];
center = (edges(1:end-1) + edges(2:end))/2;
width = diff(edges);
hold on
for i=1:length(center)
bar(center(i),vals(i),width(i),'b')
end
hold off

Answer 2

[Steven Lord]

E = [0, 0.2, 0.4, 0.6, 0.8, 1.0, 1.2, 1.4, 1.6, 1.8, 2.1, 2.7, 3.6, 5.1];
C = [10, 80, 132, 142, 138, 112, 75, 65, 52, 65, 62, 32, 35];
histogram('BinCounts', C, 'BinEdges', E)

Answer 3

[Walter Roberson]

edges = [0 : 0.2 : 1.8, 2.1, 2.7, 3.6, 5.1];

vals = [10
80
132
142
138
112
75
65
52
65
62
32
35];
centers = (edges(1:end-1) + edges(2:end));

bar(centers, vals)
set(gca, 'xtick', centers)

If you need the bars to be variable width (the full width of their bin) then more work is required, as bar() does not support that.

Answer 4

[FURKAN CEVAHIR]

Thank you. But I need the bars which show variable widths according to the size intervals. How can I do that?

Answer 5

[FURKAN CEVAHIR]

Great! Thank you so much. What if I want to plot X axis on logarithmic scale like that, Size Intervals (um) ln 0.0 - ln 0.2 ln 0.2 - ln 0.4 ln 0.4 - ln 0.6 ln 0.6 - ln 0.8 ln 0.8 - ln 1.0 ln 1.0 - ln 1.2 ln 1.2 - ln 1.4 ln 1.4 - ln 1.6 ln 1.6 - ln 1.8 ln 1.8 - ln 2.1 ln 2.1 - ln 2.7 ln 2.7 - ln 3.6 ln 3.6 - ln 5.1

[Star Strider]

As always, my pleasure!

Add 'XScale' to the set call:

set(gca, 'XTick',V1L, 'FontSize',6, 'XScale','log')