Sudden slowness of MATLAB - same code, same PC

I have had an issue where this code now runs slowly, when it was running quickly before.

The code is:

% function [Score] = Location(g,Theatre,steps,GTotal,PopNum,ThNum)
% Code to plot where max the robot is moving through a number of steps in 
% each a strategy for each of the theatres produced, a total score is then 
% outputted.
tic
% Last edited: 04/03/2015 by Pete Woodward
clear all; close all
g = 1;
PopNum = 200; % # of genes in population, KEEP EVEN
ThNum = 100; % number of theatres to generate
GenNum = 100;
steps = 200;
load('Theatre0_100_10x_10y.mat')
load('GT200.mat')
GTotal(1,:,:) = GT1;

Score = zeros([PopNum ThNum]); %initialise score array

% for each gene in the population
for s = 1:PopNum,
    % for each theatre
    for t = 1:ThNum,
        % establish a dynamic theatre that can be modified and disguarded
        DynThea = Theatre(t,:,:); 
        % change initialise location (1,1) in theatre, (2,2) with walls
        Loc = [2 2];
        % execute for 200 steps of each strategy (GTotal)
        for j = 1:steps,
            % get next step for locale - check theatre values to get a base
            % 3 value for locale, convert to base 10 for index within
            % GTotal(:,:,ind)
            % Gene consists of [N S E W C]
%             N = DynThea(Loc(1),Loc(2)-1)*81; % North Locale
%             S = DynThea(Loc(1),Loc(2)+1)*27; % South Locale
%             E = DynThea(Loc(1)+1,Loc(2))*9; % East Locale
%             W = DynThea(Loc(1)-1,Loc(2))*3; % West Locale
%             C = DynThea(Loc(1),Loc(2))*1; % Current Locale
%             LocaleB10 = N+S+E+W+C+1; % Base 10 decimal Locale
            % combining above lines into one line speeds up each call of
            % Location.m by around 4 seconds (from 11 seconds)
            step = GTotal(g,s,((DynThea(1,Loc(1),Loc(2)-1)*81)+...
                (DynThea(1,Loc(1),Loc(2)+1)*27)+...
                (DynThea(1,Loc(1)+1,Loc(2))*9)+...
                (DynThea(1,Loc(1)-1,Loc(2))*3)+...
                (DynThea(1,Loc(1),Loc(2))*1)+1));
            % check for random first, change step if random occurs
            if step == 6
                % change to appropriate random direction or pick up rubbish
                step = floor(5*rand)+1;
            end
            % check for other values or random direction
            if step == 1
                Loc(2) = Loc(2) - 1; %North
                % check for walls
                if DynThea(1,Loc(1),Loc(2)) == 2
                    Score(s,t) = Score(s,t) - 5; % hit a wall
                    Loc(2) = Loc(2) + 1;
                end
            elseif step == 2
                Loc(2) = Loc(2) + 1; % South
                % check for walls
                if DynThea(1,Loc(1),Loc(2)) == 2
                    Score(s,t) = Score(s,t) - 5; % hit a wall
                    % check if it is the first movement
                    Loc(2) = Loc(2) - 1;
                end
            elseif step == 3
                Loc(1) = Loc(1) + 1; %East
                % check for walls
                if DynThea(1,Loc(1),Loc(2)) == 2
                    Score(s,t) = Score(s,t) - 5; %hit a wall
                    % check if it is the first movement
                    Loc(1) = Loc(1) - 1;
                end
            elseif step == 4
                Loc(1) = Loc(1) - 1; % West
                % check for walls
                if DynThea(1,Loc(1),Loc(2)) == 2
                    Score(s,t) = Score(s,t) - 5; % hit a wall
                    % check if it is the first movement
                    Loc(1) = Loc(1) + 1;
                end
            elseif step == 5
                if DynThea(1,Loc(1),Loc(2)) == 0
                    % no rubbish so -1 points
                    Score(s,t) = Score(s,t) - 1; 
                else
                    % must be rubbish there
                    Score(s,t) = Score(s,t) + 10;
                    DynThea(1,Loc(1),Loc(2)) = 0; % remove the rubbish
                end
            end
        end
    end
end
toc

This ran on my PC at around 0.5 seconds using tic toc. Until I cancelled another program using Neural Networks Toolbox (using ctrl + C)

After which my code now takes 14.8 seconds using Tic Toc.

I have tried reinstalling MATLAB 2014b but this hasn't worked. I am on a trial for that but it also runs slow in my student copy of 2014a.

PC Specs in dxdiag.txt attached.

The code runs fine on the university computers so it isn't a code issue.

Any suggestions appreciated.

[James Tursa]

Have you run the profiler?

[dpb]

Sounds like possibly a case of non-release memory or somesuch? Tried a cold boot?

[Woody247]

The profiler is the Run and Time function? Yes, it gives 19.5 seconds on home PC and 6.5 seconds on university PC.

The PC has restarted multiple times and I have completely uninstalled MATLAB and reinstalled.

Running the bench function gives me good results, I think everything looks ok although haven't tried it on Uni PCs yet.

[James Tursa]

Can you compare profiler results to see if there is a particular function or line of code that has significantly different timing?

[dpb]

Have you automated updates checked? Perhaps some behind-the-scenes app has bit that you're unaware of?

What about malware of various sorts or antivirus software?

[Woody247]

James - I'll get some comparisons later tonight or tomorrow when I'm next on campus.

Dpb - I have just done a fresh install, everything is default but I presume up to date. The uni PC is running 2014a not 2014b, however my home version of 2014a also has the same issue.

I am running Avast antivirus but nothing is clogging up CPU or memory on my machine.

[dpb]

"...nothing is clogging up CPU or memory on my machine."

Something must be or symptoms wouldn't be as described.

Perhaps you're not actually comparing what you think you are? Possibly a data-specific issue or a modified version of the m-file owing to some edit/change, etc., ...???