want to display the x value of the maximum in my graph?

for the code below i want to display the maximum value of x on the graph can anyone please let me know thanks?

[GC,GR]=groupcounts (VarName8); % taking values from the excel sheet 
area=table(GC, GR); % all areas with the number of trips to each have been totaled in this table in random order
sorted_area=sortrows(area,-1); % sorting the area and number of trips in a descending order
[Highest,index]=max(GC);
plot(GR,GC,'Linewidth',1.2,'color','b'); xlabel('Area Number'); ylabel('Total Trips');
grid on
hold on
plot(GR(index),GC(index),'r*'); text(GR(index),GC(index),'\leftarrow Maximum')

[Adam Danz]

is VarName8 a column of data?

[Rehanos_boyzee]

Yes Var 8 is column of data that I'm taking importing from an excel sheet

Answer 1

[Image Analyst]

Try this:

x=[1 2 3 4 5 6];
y=[5 6 7 6 5 4];
[highest,index] = max(y)
plot(x,y); text(x(index), y(index), '\leftarrow')
ylim([4, 8]);
grid on;
caption = sprintf('   maximum point at (x,y) = (%.1f, %.1f)', x(index), highest);
text(x(index), y(index), caption, 'FontSize', 12, 'Color', 'r', 'FontWeight', 'bold');

[Rehanos_boyzee]

Thanks....

[Adam Danz]

You could insert the arrow directly within the label rather than plotting the arrow and label separately and starting the label with empty space.

x=[1 2 3 4 5 6];
y=[5 6 7 6 5 4];
[highest,index] = max(y);
plot(x,y); 
ylim([4, 8]);
grid on;
caption = sprintf('maximum point at (x,y) = (%.1f, %.1f)', x(index), highest);
text(x(index), y(index), [' \leftarrow ',caption], 'FontSize', 8.5, 'Color', 'r', 'FontWeight', 'bold');