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How to Control Mouseover Text In Matplotlib?

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How to Control Mouseover Text In Matplotlib? image

In matplotlib, you can control the text that appears when you hover over a plot by setting the hoverlabel property of the HoverTool object. By customizing the tooltips attribute of the HoverTool, you can specify the text that will be displayed when hovering over the data points on your plot. Additionally, you can format the text using HTML tags to add styling and structure to the hover text. By leveraging the tooltip feature in matplotlib, you can enhance the user experience of your plots by providing informative and visually appealing hover text.

How to display custom tooltip text in matplotlib?

To display custom tooltip text in matplotlib, you can create a custom function that will handle the display of the tooltip when the user hovers over a specific item on the plot.

Here is an example of how you can create a custom tooltip function in matplotlib:

import matplotlib.pyplot as plt

def on_hover(event): x, y = event.xdata, event.ydata text = f'Point: ({x:.2f}, {y:.2f})'

tooltip.set\_text(text)
tooltip.set\_position((x, y))
tooltip.set\_visible(True)

fig, ax = plt.subplots() ax.plot([1, 2, 3, 4], [5, 6, 7, 8])

tooltip = ax.text(0, 0, '', bbox={'facecolor': 'white', 'alpha': 0.7}) tooltip.set_visible(False)

fig.canvas.mpl_connect('motion_notify_event', on_hover)

plt.show()

In this example, we first create a custom function on_hover that will display the tooltip text when the user hovers over a point on the plot. Inside the on_hover function, we get the x and y coordinates of the mouse pointer and create a custom text string to display as the tooltip.

We then create an empty text object tooltip that will display the tooltip text on the plot. We set its initial visibility to false. Finally, we use fig.canvas.mpl_connect to connect the motion_notify_event to the on_hover function, which will display the custom tooltip text as the user hovers over points on the plot.

What is mouseover text in matplotlib?

In matplotlib, mouseover text refers to the text that appears when the mouse pointer hovers over a specific element or data point on a plot. This text typically provides additional information about the element being hovered over, such as its value or label. This feature can be useful for adding interactivity to a plot and enhancing the viewer's understanding of the data being presented.

How to show detailed information on mouse hover in matplotlib?

You can use the mpldatacursor library in Matplotlib to show detailed information on mouse hover.

First, install the mpldatacursor library if you haven't already:

pip install mpldatacursor

Then, you can use the following example code to show detailed information on mouse hover:

import matplotlib.pyplot as plt import mpldatacursor

x = [1, 2, 3, 4, 5] y = [2, 3, 5, 7, 11] labels = ['A', 'B', 'C', 'D', 'E']

fig, ax = plt.subplots() ax.plot(x, y)

mpldatacursor.datacursor(hover=True, formatter='{label}'.format, display='multiple', labels=labels)

plt.show()

In this example, the mpldatacursor.datacursor() function is used to enable the hover feature. The formatter parameter is used to specify the format of the information to be displayed on hover. In this case, the labels of the data points are displayed. The hover=True parameter enables the hover functionality.

You can customize the information displayed on hover by changing the formatter parameter and the labels parameter to suit your specific needs.