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Figure 6.1: 面向不同目标的可视化解决方案

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Figure 6.2: 大N问题和大P问题

<p>一般来说，可视化中的大N问题是因为数据点过多导致可视化过程卡顿，甚至因内存不足而无法实现。下面我们举一个例子，比如我们构造100万个点，它们有横坐标x和纵坐标y。构造代码如下：</p>

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<div class="sourceCode cell-code" id="cb1"><pre class="sourceCode r code-with-copy"><code class="sourceCode r"><span id="cb1-1"><a href="#cb1-1" aria-hidden="true" tabindex="-1"></a><span class="fu">library</span>(pacman)</span>

<span id="cb1-2"><a href="#cb1-2" aria-hidden="true" tabindex="-1"></a><span class="fu">p_load</span>(ggplot2,pryr,bench,fs,tidyst)</span>

<span id="cb1-2"><a href="#cb1-2" aria-hidden="true" tabindex="-1"></a><span class="fu">p_load</span>(ggplot2,pryr,bench,fs,tidyfst)</span>

<span id="cb1-3"><a href="#cb1-3" aria-hidden="true" tabindex="-1"></a></span>

<span id="cb1-4"><a href="#cb1-4" aria-hidden="true" tabindex="-1"></a>x <span class="ot">=</span> <span class="fu">rnorm</span>(<span class="fl">1e6</span>,<span class="at">mean =</span> <span class="dv">6</span>)</span>

<span id="cb1-5"><a href="#cb1-5" aria-hidden="true" tabindex="-1"></a>y <span class="ot">=</span> <span class="fu">rnorm</span>(<span class="fl">1e6</span>) <span class="sc">+</span> <span class="dv">2</span> <span class="sc">+</span> <span class="fl">1.5</span> <span class="sc">*</span> x</span>