<div>np.meshgrid, indexing, reshape</div><div><br /></div><div>09.01.2021, 22:30, "Joseph Fox-Rabinovitz" <jfoxrabinovitz@gmail.com>:</div><blockquote><div dir="ltr">What other ways have you tried?<br /><br /><div class="f13ca48719c8a60033905b23b39675agmail_quote"><div class="334d7d341e3233c5b27ca91297445127gmail_attr" dir="ltr">On Sat, Jan 9, 2021 at 2:15 PM <<a href="mailto:klark--kent@yandex.ru" target="_blank">klark--kent@yandex.ru</a>> wrote:<br /></div><blockquote class="f13ca48719c8a60033905b23b39675agmail_quote" style="border-left-color:rgb( 204 , 204 , 204 );border-left-style:solid;border-left-width:1px;margin:0px 0px 0px 0.8ex;padding-left:1ex">Hello. <span style="color:rgb( 12 , 13 , 14 );font-family:'helvetica neue' , 'helvetica' , 'arial' , sans-serif;font-size:15px">There is a random 1D array m_0 with size 3000, for example:</span><pre style="border:0px;border-radius:5px;box-sizing:inherit;font-family:'consolas' , 'menlo' , 'monaco' , 'lucida console' , 'liberation mono' , 'dejavu sans mono' , 'bitstream vera sans mono' , 'courier new' , monospace , sans-serif;line-height:1.30769;margin-top:0px;max-height:300px;overflow:auto;padding:12px;vertical-align:baseline"><code style="border:0px;box-sizing:inherit;font-family:inherit;font-style:inherit;font-variant:inherit;font-weight:inherit;line-height:inherit;margin:0px;max-height:300px;padding:0px;vertical-align:baseline">m_0 = np.array([<span style="border:0px;box-sizing:inherit;font:inherit;margin:0px;padding:0px;vertical-align:baseline">0</span>, <span style="border:0px;box-sizing:inherit;font:inherit;margin:0px;padding:0px;vertical-align:baseline">1</span>, <span style="border:0px;box-sizing:inherit;font:inherit;margin:0px;padding:0px;vertical-align:baseline">2</span>])
</code></pre><p style="border:0px;box-sizing:inherit;color:rgb( 12 , 13 , 14 );font-family:'helvetica neue' , 'helvetica' , 'arial' , sans-serif;font-size:15px;line-height:inherit;margin-left:0px;margin-right:0px;margin-top:0px;padding:0px;vertical-align:baseline">I need to generate two 1D arrays:</p><pre style="border:0px;border-radius:5px;box-sizing:inherit;font-family:'consolas' , 'menlo' , 'monaco' , 'lucida console' , 'liberation mono' , 'dejavu sans mono' , 'bitstream vera sans mono' , 'courier new' , monospace , sans-serif;line-height:1.30769;margin-top:0px;max-height:300px;overflow:auto;padding:12px;vertical-align:baseline"><code style="border:0px;box-sizing:inherit;font-family:inherit;font-style:inherit;font-variant:inherit;font-weight:inherit;line-height:inherit;margin:0px;max-height:300px;padding:0px;vertical-align:baseline">m_1 = np.array([<span style="border:0px;box-sizing:inherit;font:inherit;margin:0px;padding:0px;vertical-align:baseline">0</span>, <span style="border:0px;box-sizing:inherit;font:inherit;margin:0px;padding:0px;vertical-align:baseline">1</span>, <span style="border:0px;box-sizing:inherit;font:inherit;margin:0px;padding:0px;vertical-align:baseline">2</span>, <span style="border:0px;box-sizing:inherit;font:inherit;margin:0px;padding:0px;vertical-align:baseline">0</span>, <span style="border:0px;box-sizing:inherit;font:inherit;margin:0px;padding:0px;vertical-align:baseline">1</span>, <span style="border:0px;box-sizing:inherit;font:inherit;margin:0px;padding:0px;vertical-align:baseline">2</span>, <span style="border:0px;box-sizing:inherit;font:inherit;margin:0px;padding:0px;vertical-align:baseline">0</span>, <span style="border:0px;box-sizing:inherit;font:inherit;margin:0px;padding:0px;vertical-align:baseline">1</span>, <span style="border:0px;box-sizing:inherit;font:inherit;margin:0px;padding:0px;vertical-align:baseline">2</span>])
m_2 = np.array([<span style="border:0px;box-sizing:inherit;font:inherit;margin:0px;padding:0px;vertical-align:baseline">0</span>, <span style="border:0px;box-sizing:inherit;font:inherit;margin:0px;padding:0px;vertical-align:baseline">0</span>, <span style="border:0px;box-sizing:inherit;font:inherit;margin:0px;padding:0px;vertical-align:baseline">0</span>, <span style="border:0px;box-sizing:inherit;font:inherit;margin:0px;padding:0px;vertical-align:baseline">1</span>, <span style="border:0px;box-sizing:inherit;font:inherit;margin:0px;padding:0px;vertical-align:baseline">1</span>, <span style="border:0px;box-sizing:inherit;font:inherit;margin:0px;padding:0px;vertical-align:baseline">1</span>, <span style="border:0px;box-sizing:inherit;font:inherit;margin:0px;padding:0px;vertical-align:baseline">2</span>, <span style="border:0px;box-sizing:inherit;font:inherit;margin:0px;padding:0px;vertical-align:baseline">2</span>, <span style="border:0px;box-sizing:inherit;font:inherit;margin:0px;padding:0px;vertical-align:baseline">2</span>])
</code></pre><p style="border:0px;box-sizing:inherit;color:rgb( 12 , 13 , 14 );font-family:'helvetica neue' , 'helvetica' , 'arial' , sans-serif;font-size:15px;line-height:inherit;margin-left:0px;margin-right:0px;margin-top:0px;padding:0px;vertical-align:baseline">Is there faster way to do it than this one:</p><pre style="border:0px;border-radius:5px;box-sizing:inherit;font-family:'consolas' , 'menlo' , 'monaco' , 'lucida console' , 'liberation mono' , 'dejavu sans mono' , 'bitstream vera sans mono' , 'courier new' , monospace , sans-serif;line-height:1.30769;margin-top:0px;max-height:300px;overflow:auto;padding:12px;vertical-align:baseline"><code style="border:0px;box-sizing:inherit;font-family:inherit;font-style:inherit;font-variant:inherit;font-weight:inherit;line-height:inherit;margin:0px;max-height:300px;padding:0px;vertical-align:baseline"><span style="border:0px;box-sizing:inherit;font:inherit;margin:0px;padding:0px;vertical-align:baseline">import</span> numpy <span style="border:0px;box-sizing:inherit;font:inherit;margin:0px;padding:0px;vertical-align:baseline">as</span> np
<span style="border:0px;box-sizing:inherit;font:inherit;margin:0px;padding:0px;vertical-align:baseline">import</span> time
N = <span style="border:0px;box-sizing:inherit;font:inherit;margin:0px;padding:0px;vertical-align:baseline">3</span>
m_0 = np.arange(N)

t = time.time()
m_1 = np.tile(m_0, N)
m_2 = np.repeat(m_0, N)
t = time.time() - t</code></pre><pre style="border:0px;border-radius:5px;box-sizing:inherit;font-family:'consolas' , 'menlo' , 'monaco' , 'lucida console' , 'liberation mono' , 'dejavu sans mono' , 'bitstream vera sans mono' , 'courier new' , monospace , sans-serif;line-height:1.30769;margin-top:0px;max-height:300px;overflow:auto;padding:12px;vertical-align:baseline"><code style="border:0px;box-sizing:inherit;font-family:inherit;font-style:inherit;font-variant:inherit;font-weight:inherit;line-height:inherit;margin:0px;max-height:300px;padding:0px;vertical-align:baseline">I tried other ways but they are slower or have the same time. Other NumPy operations in my code 10-100 times faster. </code>Why the repeating an array is so slow? I need 10 times speed up. Thank you for your attantion to my problem.</pre>_______________________________________________<br />
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