MATLAB: Transform a set of “if” arguments into a unified “for” function

for loop

Hello kind people,

I'm trying to optimize this segment of a function. Currently, it will give an output to the user when n_dice =< than 3.

if(n_dice==1)
		Z= randi(6,1,n_trials);
end
if(n_dice==2)
		Z= randi(6,1,n_trials) + randi(6,1,n_trials);				
end
if(n_dice==3)
		Z= randi(6,1,n_trials) + randi(6,1,n_trials) + randi(6,1,n_trials);
end

I'm trying to chage it so that it will accept any number of n_dice, maybe by using a for…? I've tried stuff like

sdice = randi(6,1,n_trials);
for i = 1:n_dice
    X = sdice(i);
end
Z = sum(X)

Could you please suggest something?

Best Answer

if n_dice==1
    Z=randi(6,1,n_trials);
else
    Z=sum(randi(6,n_dice,n_trials));
end

Related Solutions

MATLAB: Probability of exactly one even number

Very close but you need to check if just one even number was thrown OUTSIDE the inner loop over j. Also, a tip: to determine if something is even you can use rem(value, 2) rather than all that dividing stuff you're doing. Try this:

clear;
clc;
nDice = 3; % Number of dice
nTrials = 1e6; % Number of trials
singleCount = 0; % Count of how many trials have 1 even number
for i = 1:nTrials
	% For this trial, initialize the number of even numbered dice thrown.
	evenNumberCount = 0;
	% Make nDice throws detecting if the throw was an even number.
	for j = 1 : nDice
		thisDicesValue = randi(6);
		evenNumberCount = evenNumberCount + (rem(thisDicesValue, 2) == 0);
	end
	% See if only ONE of those throws was an even number during this trial.
	if evenNumberCount == 1
		% Only one even number was thrown
		singleCount = singleCount + 1;
	end
end
prob = singleCount / nTrials
fprintf('Found %d experiments where exactly 1 die in %d throws of %d dice had one even number.\n',...
	singleCount, nTrials, nDice);

and adapt as needed.

MATLAB: Multiple Dice Rolls Help

Sum of dice is just sum(diceValues). And you will not need the "for die" loop as you only get a single sum.

(By the way, the entire function can be done as a single expression, including the histogram.)

Best Answer

Related Solutions

MATLAB: Probability of exactly one even number

MATLAB: Multiple Dice Rolls Help

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