Plotly调整Y轴范围时如何保持Marker尺寸不变？

我使用Plotly的Scatter创建了rug plot，代码如下：

fig = go.Figure(go.Scatter(
    x = group_sample_clean,
    y = [0]*len(group_sample_clean),
    mode = 'markers',
    marker_color="lightskyblue",
    marker_line_width=2, 
    marker_size=30,
    marker_symbol = 'line-ns',
    showlegend = False
    )
)

fig.add_trace(go.Scatter(
    x = single_sample,
    y = [0],
    mode = 'markers',
    marker_color = 'orange',
    marker_symbol = 'star',
    marker_size = 40,
    showlegend = False
    ))

fig.update_xaxes(showgrid=False)
fig.update_yaxes(showgrid=False, automargin=True, showticklabels=False)
fig.update_layout(title_text=f'{feature} samples in {key} in {age_group}')
fig.show()

当前图表的rug线条过长，我希望实现紧凑的rug线条效果，但常规调整轴范围的方法无效——因为line-ns这类标记的尺寸会自动适配轴维度变化，请问有什么解决办法？

核心原因是line-ns这类符号标记的尺寸是相对轴坐标空间缩放的，而非固定像素尺寸，因此调整轴范围无法控制线条长度。推荐两种可行方案：

方法1：改用Shape绘制固定长度的Rug线 #

放弃使用Scatter的marker符号，直接通过add_shape批量绘制垂直短线，线条长度可固定为像素比例或画布比例，不受轴范围影响：

# 初始化空图表
fig = go.Figure()

# 批量绘制分组样本的rug线
for x_val in group_sample_clean:
    fig.add_shape(
        type="line",
        x0=x_val, y0=-0.02,
        x1=x_val, y1=0.02,
        line=dict(color="lightskyblue", width=2)
    )

# 添加单个样本的星号标记
fig.add_trace(go.Scatter(
    x = single_sample,
    y = [0],
    mode = 'markers',
    marker_color = 'orange',
    marker_symbol = 'star',
    marker_size = 40,
    showlegend = False
))

# 调整轴与布局设置
fig.update_xaxes(showgrid=False)
fig.update_yaxes(
    showgrid=False, 
    showticklabels=False,
    range=[-0.05, 0.05],  # 固定y轴范围，避免自动缩放
    fixedrange=True
)
fig.update_layout(title_text=f'{feature} samples in {key} in {age_group}')
fig.show()

方法2：锁定轴缩放比例控制Marker线条长度 #

如果坚持使用Scatter的marker符号，可以通过锁定y轴与x轴的缩放比例，强制marker线条长度固定：

fig = go.Figure(go.Scatter(
    x = group_sample_clean,
    y = [0]*len(group_sample_clean),
    mode = 'markers',
    marker_color="lightskyblue",
    marker_line_width=2, 
    marker_size=10,  # 缩小尺寸，配合缩放比例控制线条长度
    marker_symbol = 'line-ns',
    showlegend = False
))

fig.add_trace(go.Scatter(
    x = single_sample,
    y = [0],
    mode = 'markers',
    marker_color = 'orange',
    marker_symbol = 'star',
    marker_size = 20,
    showlegend = False
))

fig.update_xaxes(showgrid=False)
fig.update_yaxes(
    showgrid=False, 
    showticklabels=False,
    scaleanchor="x",  # 强制y轴与x轴缩放比例一致
    scaleratio=0.05,  # 调整此值控制rug线条长度，数值越小线条越短
    fixedrange=True
)
fig.update_layout(title_text=f'{feature} samples in {key} in {age_group}')
fig.show()

内容的提问来源于stack exchange，提问作者user20646185