><span class="op">$</span><span class="va">x</span> <span class="op">=</span> <span class="fu">keras</span><span class="fu">::</span><span class="fu"><a href="https://rdrr.io/pkg/keras/man/k_reshape.html" class="external-link">k_reshape</a></span><span class="op">(</span><span class="va">mnist_train</span><span class="op">$</span><span class="va">x</span>,shape <span class="op">=</span> <span class="fu"><a href="https://rdrr.io/r/base/c.html" class="external-link">c</a></span><span class="op">(</span><span 