Generating a histogram from a cell array using cell2mat

Hi All,

I am attempting to generate a histogram from a cell array using the cell2mat function. Using the code below, I am receiving the following error:

Error using histogram>parseinput (line 306)

Trailing input arguments must occur in name-value pairs.

Error in histogram (line 145)

[opts,passthrough,dispatchToCategorical] = parseinput(args,firstaxesinput);

Error in untitled (line 51)

histogram (R0array,[0:0.1:3],"probability");

I am very new to coding in matlab, and I assumed that once I transitioned the cell array to a double array the histogram would play nice. I am confused by what is meant by a "name-value pair." Any help would be greatly appreciated!

%Total number of replicates

n=1000;

%Generating cells to store results

result=cell(n,1);

%Generating cells to store values for R0

R0result=cell(n,1);

%Figure hold to plot all 1000 replicates on a single graph

figure; hold on

%Latin hypercube with 1000 values generated for 11 parameters

LHS=lhdesign(1000,11);

for k=1:n

%Initial conditions

n=16956;

y20=10;

y30=0;

%Parameters I am hoping to sample randomly using LHS instead of "rand"

p=(407-341)*rand+341;

d=(1/42-1/50)*rand+1/50;

yc=(4.923*10^-3-8.8*10^-5)*rand+8.8*10^-5;

yi=(4.923*10^-3-8.8*10^-5)*rand+8.8*10^-5;

a=(1/30-1/120)*rand+1/120;

r=(0.30-.10)*rand+0.1;

i=(1/4-1/15)*rand+1/15;

bc=(1.5*10^-3-1.5*10^-5)*rand+1.5*10^-5;

bi=(1.5*10^-3-1.5*10^-5)*rand+1.5*10^-5;

c=(50-5)*rand+5;

tr=(0.2-0.01)*rand+0.01;

%Time step and length

tspan=[(1:0.1:500)];

%Function definition

[t,y] = ode23s(@(t,y) [p*(1-yc-yi) + a*y(2) + tr*y(3) - (c*bc*y(2)*y(1))/n - (c*bi*y(3)*y(1))/n - d*y(1); p*yc + (c*bc*y(2)*y(1))/n + (c*bi*y(3)*y(1))/n - a*y(2) - r*i*y(2) - d*y(2); p*yi + r*i*y(2) + - d*y(3)-tr*y(3);], tspan, [n y20 y30]);

%Storing results in cells

result{k} = y;

%Graphing all replicates for y(2).

plot(t, y(:,2));

%Generating an R0 for each iteration of the random parameters

R0 = (c*bc+r*i*c*(bi/d))/(a+r*i+d);

R0result{k}= R0;

end

histogram (R0array,[0:0.1:3],"probability");

R0array = cell2mat(R0result);

[KSSV]

What is dimension of R0result? What is size of each cell array?

[Robert Pearhill]

The R0 array is 1000x1, and each cell is a single number. Atsushi Ueno provided the answer below by noting that I needed to include an additional property name. Thank you for responding,though! I really appreciate all the support this site gives!

Answer 1

[Atsushi Ueno]

Histogram plot - MATLAB - MathWorks

histogram(___,Name,Value) specifies additional options with one or more Name,Value pair arguments using any of the previous syntaxes. For example, you can specify 'BinWidth' and a scalar to adjust the width of the bins, or 'Normalization' with a valid option ('count', 'probability', 'countdensity', 'pdf', 'cumcount', or 'cdf') to use a different type of normalization. For a list of properties, see Histogram Properties.

So, you need additinal property name 'Normalization'.

histogram (R0array,[0:0.1:3],'Normalization','probability');

[Robert Pearhill]

This fixed it! Thank you so much!