在图上用数据名替换x轴

There are three data points in column vector SP that I am trying to plot. Since I am new to MatLab, I still face following issue with plotting:

我试图绘制列向量SP中有三个数据点。由于我是MatLab的新手，我仍然面临以下绘图问题：

Problem 1: How do I replace X-axis with the name of each data point?

问题1：如何用每个数据点的名称替换X轴？

Problem 2: How do I add the value of each data point on the top of every point on the plot?

问题2：如何在绘图上的每个点的顶部添加每个数据点的值？

Note: From a reply to my previous question, I entered the name of each data point as a cell array (not as a character), but that does not work.

注意：从对上一个问题的回复中，我将每个数据点的名称输入为单元格数组（而不是字符），但这不起作用。

This is my code:

这是我的代码：

SP = [4.3376 4.4005 5.0925];
plot(SP,'-o');
title('SP and YP monthly returns');
xlabel('Monthly time series');
axis([0 4 0 7]);
labelCell = {'' '' 'Asset1' '' 'Asset2' '' 'Asset3' ''};
set(gca, 'xTickLabel', cellstr(MMM));
ylabel('Sharpe Ratio');

My output in MatLab:

我在MatLab中的输出：

My desired output:

我想要的输出：

1 个解决方案

#1

1. It isn't working because you aren't using the correct variable when you are setting the XTickLabels. You are using MMM. Instead, it should be:

   它不起作用，因为在设置XTickLabel时没有使用正确的变量。您正在使用MMM。相反，它应该是：

   labelCell = {'' '' 'Asset1' '' 'Asset2' '' 'Asset3' ''};
   set(gca, 'xTickLabel', labelCell);
   

   A better option that would allow you to not have to create the '' labels would be to manually specify the XTick locations as well

   一个更好的选项可以让您不必创建''标签，也可以手动指定XTick位置

   set(gca, 'XTick', 1:numel(SP), 'XTickLabel', {'Asset1', 'Asset2', 'Asset3'})
   

2. You can add text objects to your plot to place the labels above your data

   您可以在绘图中添加文本对象，将标签放在数据上方

   for k = 1:numel(SP)
       text(k, SP(k), {num2str(SP(k)), ''}, ...
           'HorizontalAlignment', 'center', ...
           'verticalalignment', 'bottom')
   end
   

   Note that for the String, I use a cell array with an empty second element. This inserts an empty line between the label and the datapoint rather than manually having to compute the y value.

   请注意，对于String，我使用带有空第二个元素的单元格数组。这会在标签和数据点之间插入一条空行，而不是手动计算y值。