Why am I getting an error message on my code?

function [estPiAve, estPiStD] = estPiStats(numThrows,numTrials)
estPiValues = zeros([numTrials 1]);
% populate the estPiValues vector
for i = 1:numTrials
    estPiValues(i) = estPi(numThrows);
end
estPiAve = mean(estPiValues);
estPiStD = std(estPiValues);
plot(estPiValues,'o')
hold on
plot([1, numTrials], pi^[-1, 1],'k');
plot([1, numTrials], (estPiAve+1.96^estPiStD)^[-1, 1],'--k');
plot([1, numTrials], (estPiAve-1.96^estPiStD)^[-1, 1]),'--k';
hold off
end 

Not enough input arguments.

Error in estPiStats (line 3)

estPiValues = zeros([numTrials 1]);

Answer 1

[Cameron]

Try this instead

estPiValues = zeros(numTrials,1);

Answer 2

[VBBV]

numThrows = 10;
numTrials  = 30;
[estPiAve, estPiStD] = estPiStats(numThrows,numTrials)  % provide all input arguments when calling function

estPiAve = 0.5101

estPiStD = 0.2798

function [estPiAve, estPiStD] = estPiStats(numThrows,numTrials)
estPiValues = zeros([numTrials 1]);
% populate the estPiValues vector
for i = 1:numTrials
    estPiValues(i) = rand(1); %estPi(numThrows);
end
estPiAve = mean(estPiValues);
estPiStD = std(estPiValues);
plot(estPiValues,'o')
hold on
plot([1, numTrials], pi.^[-1, 1],'k');
plot([1, numTrials], (estPiAve+1.96^estPiStD).^[-1, 1],'--k');
plot([1, numTrials], (estPiAve-1.96^estPiStD).^[-1, 1]),'--k';
hold off
end 

[VBBV]

if you dont provide all input arguments to the function, then it results in such error

numThrows = 10;
numTrials  = 30;
[estPiAve, estPiStD] = estPiStats(numThrows)  % if you dont provide enough input arguments it will throw such error

Not enough input arguments.

Error in solution>estPiStats (line 5)
estPiValues = zeros([numTrials 1]);

function [estPiAve, estPiStD] = estPiStats(numThrows,numTrials)
estPiValues = zeros([numTrials 1]);
% populate the estPiValues vector
for i = 1:numTrials
    estPiValues(i) = rand(1); %estPi(numThrows);
end
estPiAve = mean(estPiValues);
estPiStD = std(estPiValues);
plot(estPiValues,'o')
hold on
plot([1, numTrials], pi.^[-1, 1],'k');
plot([1, numTrials], (estPiAve+1.96^estPiStD).^[-1, 1],'--k');
plot([1, numTrials], (estPiAve-1.96^estPiStD).^[-1, 1]),'--k';
hold off
end