#----------------------------------------------------------
#	FOR SLOPE
#----------------------------------------------------------
my $mean_score = &average(\@allscores);
$mean_score= sprintf("%.0f",$mean_score);
my $stdev_score = &stdev(\@allscores);
$stdev_score= sprintf("%.3f",$stdev_score);


my @list_of_x;
my @list_of_y;
my @list_of_z;
my $num_scores = @allscores;

# Get list of x
# since each date is just ... yeah... 1
my $dates = 1;
foreach ($i=0; $i<$num_scores; $i++){
	@list_of_x[$i] = ($dates-$mean_score)/$stdev_score;
	@list_of_x[$i]= sprintf("%.2f",@list_of_x[$i]);
	$dates++;
}
# Get list of y
foreach ($i=0; $i<$num_scores; $i++){
	@list_of_y[$i] = (@allscores[$i]-$mean_score)/$stdev_score;
	@list_of_y[$i]= sprintf("%.2f",@list_of_y[$i]);
}

# Get the list of z-scores
for($i=0; $i<$num_scores; $i++){
	@list_of_z[$i]= (@list_of_x[$i] * @list_of_y[$i]);
	@list_of_z[$i]= sprintf("%.2f",@list_of_z[$i]);
}

# add up the z-scores
my $sigma = 0;
for($i=0; $i<$num_scores; $i++){
	$sigma = ($sigma + @list_of_z[$i]);
}

# get the correlation
my $correl = $sigma/($num_scores-1);

# get the slope
my $stdev_x = &stdev(\@list_of_x);
my $stdev_y = &stdev(\@list_of_y);
my $slope = $correl * ($stdev_x / $stdev_y);
$slope= sprintf("%.2f",$slope);


# add slope to each y ... y is each score
my @trendline;
for($i=0; $i<$num_scores; $i++){
	@trendline[$i] = @allscores[$i]+$slope;
	@trendline[$i] = sprintf("%.4f",@trendline[$i]);
}

#create the data for transfer to the graph program
$trendlineString = join(',',@trendline);