% Psychtoolbox:PsychProbability. % % Computation/Evaluation of probability distributions, basic sampling and % randomization. % % help Psychtoolbox % For an overview, triple-click me & hit enter. % % BalanceFactors - Balance a set of factors given the factor levels. % BalanceTrials - Balance a set of factors given the factor levels. Takes alternative parameters wrt. BalanceFactors. % BuildMarkovK - Build covariance matrix for Markov process. % ChiSqrCumulative - Chi-squared distribution probability function. % ChiSquarePDF - Chi-squared distribution PDF. % ChooseKFromN - Randomly choose k distinct integers out of n. % ClockRandSeed - Seed rand() and randn() from clock. % CoinFlip - Bernoulli random variable. % CoinFlipPDF - Bernoulli distribution PDF. % ColMean - Take column means, works for one row matrices. % ColStd - Take column stds, works for one row matrices. % CombVec - Generate all possible combinations of input vectors. % CovToCorr - Compute matrix of correlations from covariance. % FindNeighborCorr - Find nearest neighbor correlations in data set. % MultiNormalDraw - Draw vectors from multivariate normal. % MultiNormalPDF - Compute multivariate normal PDF. % NormalCumulative - Univariate normal CDF % NormalDraw - Draw from univariate normal. % NormalPDF - Univariate normal PDF. % NormalProb - Compute probability of univariate normal in interval. % NRandPerm - Randomly select elements from a random permutation. % RandDim - Randomize matrix along any dimension. % Randi - Get random integer sample. Same as Ranint, but Denis prefers it. % RandLim - Generates a matrix of random numbers between a lower and upper limit. % RandSample - Get a random sample from a list. % RandSel - Randomly select elements from matrix, elements are replenished. % Ranint - Get random integer sample. Same as Randi, but David prefers it. % Sample - Get a random sample from a list. % Shuffle - Randomly reorder the entries of vector/matrix. % UniqueAndN - Returns unique elements of array and the number of times each element occurs in the array. % UniqueNoSorting - Returns elements of array in order of appearance or disappearance. % URandSel - Randomly select elements from matrix, elements are not replenished. % % % Combining CombVec and RandDim % Using CombVec and RandDim, it is very simple to generate all trials % in an experiment with a factorial design and then randomize these % trials: % cond_a = [1 2]; cond_b = [120 180]; ntrial = 2; % trial = CombVec(cond_a,cond_b); % trial = % 1 2 1 2 % 120 120 180 180 % % trial = repmat(trial,1,ntrial); % each combination of conditions occurs ntrial times % trial(end+1,:) = [1:size(trial,2)]; % append trial number % trial = RandDim(trial,2); % shuffle trial order % % trial = % 2 1 1 2 1 1 2 2 % 120 180 180 180 120 120 120 180 % 6 3 7 8 5 1 2 4 % % % BalanceFactors.m was contributed by David E. Fencsik (fencsik@gmail.com), thanks!