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note about numpy in-place ops
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@ -235,6 +235,8 @@ Bezanson, J., Karpinski, S., Shah, V.B. and Edelman, A. (2012), “Julia: A fast
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<br>
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<br>
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@ -243,7 +245,7 @@ Bezanson, J., Karpinski, S., Shah, V.B. and Edelman, A. (2012), “Julia: A fast
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<col width="511">
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<col width="690">
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<tr>
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<td height="57" bgcolor="#0066cc" style="border: none; padding: 0in">
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<td height="59" bgcolor="#0066cc" style="border: none; padding: 0in">
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<p align="center"><font color="#ffffff"><font face="Arial"><font size="5" style="font-size: 18pt"><b>Task</b></font></font></font></p>
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</td>
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<td bgcolor="#0066cc" style="border: none; padding: 0in">
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@ -264,9 +266,9 @@ Bezanson, J., Karpinski, S., Shah, V.B. and Edelman, A. (2012), “Julia: A fast
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</td>
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</tr>
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<tr>
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<td colspan="6" height="70" bgcolor="#ffffff" style="border: none; padding: 0in" id="creating">
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<td colspan="6" height="70" bgcolor="#ffffff" style="border: none; padding: 0in">
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<p align="center"><font face="Arial"><font size="4" style="font-size: 14pt"><b>CREATING
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MATRICES </b></font></font><br>[<a href='#cheat_overview'>back to cheat sheet overview</a>]</p>
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MATRICES</b></font></font></p>
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</td>
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</tr>
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<tr valign="top">
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@ -313,10 +315,15 @@ Bezanson, J., Karpinski, S., Shah, V.B. and Edelman, A. (2012), “Julia: A fast
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3</font></font></p>
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</td>
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<td bgcolor="#cfe7f5" style="border-top: none; border-bottom: none; border-left: 1px dotted #000000; border-right: 1px dotted #000000; padding: 0in 0.02in">
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<p align="left"><font face="Andale Mono"><font size="1" style="font-size: 8pt"><font color="#ff420e"><font size="2" style="font-size: 10pt"><b>P></b></font></font>
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a = np.array([[1],[2],[3]])<br><br><font color="#ff420e"><font size="2" style="font-size: 10pt"><b>P></b></font></font>
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a<br>array([[1],<br> [2],<br>
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[3]])</font></font></p>
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<p align="left"><font color="#ff420e"><font face="Andale Mono"><font size="2" style="font-size: 10pt"><b>P></b></font></font></font>
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<font face="Andale Mono"><font size="1" style="font-size: 8pt">a</font></font><font color="#2fff12">
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</font><font color="#000000"><font face="Andale Mono"><font size="1" style="font-size: 8pt">=
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np.array([1,2,3]).reshape(1,3)</font></font></font></p>
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<p align="left"><font face="Andale Mono"><font size="1" style="font-size: 8pt"><br></font></font><font color="#ff420e"><font face="Andale Mono"><font size="2" style="font-size: 10pt"><b>P></b></font></font></font>
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<font color="#000000"><font face="Andale Mono"><font size="1" style="font-size: 8pt">b.shape<br>(1,
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3)</font></font></font></p>
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<p align="left"><br>
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</p>
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</td>
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<td bgcolor="#cfe7f5" style="border-top: none; border-bottom: none; border-left: 1px dotted #000000; border-right: 1px dotted #000000; padding: 0in 0.02in">
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<p align="left"><font face="Andale Mono"><font size="1" style="font-size: 8pt"><font color="#0000ff"><font size="2" style="font-size: 10pt"><b>R></b></font></font>
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@ -345,6 +352,14 @@ Bezanson, J., Karpinski, S., Shah, V.B. and Edelman, A. (2012), “Julia: A fast
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<p align="left"><font face="Andale Mono"><font size="1" style="font-size: 8pt"><font color="#ff420e"><font size="2" style="font-size: 10pt"><b>P></b></font></font>
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b = np.array([1,2,3])<br><br><font color="#ff420e"><font size="2" style="font-size: 10pt"><b>P></b></font></font>
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b<br>array([1, 2, 3])</font></font></p>
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<p align="left"><font face="Andale Mono"><font size="1" style="font-size: 8pt">#
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note that numpy doesn't have <br># explicit “row-vectors”, but
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1-D <br># arrays</font></font></p>
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<p style="margin-bottom: 0in"><font face="Liberation Serif, serif"><font size="3" style="font-size: 12pt"><font color="#ff420e"><font face="Andale Mono"><font size="2" style="font-size: 10pt"><b>P></b></font></font></font><font color="#2fff12">
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</font><font color="#000000"><font face="Andale Mono"><font size="1" style="font-size: 8pt">b.shape</font></font></font></font></font></p>
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<p style="margin-bottom: 0in"><font face="Andale Mono"><font size="1" style="font-size: 8pt">(3,)</font></font></p>
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<p align="left"><br>
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</p>
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</td>
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<td bgcolor="#ffffff" style="border-top: none; border-bottom: none; border-left: 1px dotted #000000; border-right: 1px dotted #000000; padding: 0in 0.02in">
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<p align="left"><font face="Andale Mono"><font size="1" style="font-size: 8pt"><font color="#0000ff"><font size="2" style="font-size: 10pt"><b>R></b></font></font>
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@ -434,7 +449,7 @@ Bezanson, J., Karpinski, S., Shah, V.B. and Edelman, A. (2012), “Julia: A fast
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</td>
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<td bgcolor="#cfe7f5" style="border-top: none; border-bottom: none; border-left: 1px dotted #000000; border-right: 1px dotted #000000; padding: 0in 0.02in">
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<p align="left"><font face="Andale Mono"><font size="1" style="font-size: 8pt"><font color="#ff420e"><font size="2" style="font-size: 10pt"><b>P></b></font></font>
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np.ones([3,2])<br>array([[ 1., 1.],<br>
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np.ones((3,2))<br>array([[ 1., 1.],<br>
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[ 1., 1.],<br> [ 1., 1.]])</font></font></p>
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</td>
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<td bgcolor="#cfe7f5" style="border-top: none; border-bottom: none; border-left: 1px dotted #000000; border-right: 1px dotted #000000; padding: 0in 0.02in">
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@ -519,9 +534,9 @@ Bezanson, J., Karpinski, S., Shah, V.B. and Edelman, A. (2012), “Julia: A fast
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</td>
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</tr>
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<tr>
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<td colspan="6" height="128" bgcolor="#ffffff" style="border: none; padding: 0in" id='accessing'>
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<td colspan="6" height="128" bgcolor="#ffffff" style="border: none; padding: 0in">
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<p align="center"><font face="Arial"><font size="4" style="font-size: 14pt"><b>ACCESSING
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MATRIX ELEMENTS</b></font></font><br>[<a href='#cheat_overview'>back to cheat sheet overview</a>]</p>
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MATRIX ELEMENTS</b></font></font></p>
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</td>
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</tr>
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<tr valign="top">
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@ -714,9 +729,9 @@ Bezanson, J., Karpinski, S., Shah, V.B. and Edelman, A. (2012), “Julia: A fast
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</td>
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</tr>
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<tr>
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<td colspan="6" height="128" bgcolor="#ffffff" style="border: none; padding: 0in" id="manipulating">
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<td colspan="6" height="128" bgcolor="#ffffff" style="border: none; padding: 0in">
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<p align="center"><font face="Arial"><font size="4" style="font-size: 14pt"><b>MANIPULATING
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SHAPE AND DIMENSIONS</b></font></font><br>[<a href='#cheat_overview'>back to cheat sheet overview</a>]</p>
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SHAPE AND DIMENSIONS</b></font></font></p>
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</td>
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</tr>
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<tr valign="top">
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@ -772,10 +787,10 @@ Bezanson, J., Karpinski, S., Shah, V.B. and Edelman, A. (2012), “Julia: A fast
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A = np.array([[1,2,3],[4,5,6],[7,8,9]])<br><br><font color="#ff420e"><font size="2" style="font-size: 10pt"><b>P></b></font></font>
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A<br>array([[1, 2, 3],<br> [4, 5, 9],<br>
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[7, 8, 9]])<br><br><font color="#ff420e"><font size="2" style="font-size: 10pt"><b>P></b></font></font>
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total_elements = A.shape[0] * A.shape[1]<br><br><font color="#ff420e"><font size="2" style="font-size: 10pt"><b>P></b></font></font>
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B = A.reshape(1, total_elements) <br><br># or
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A.reshape(1,9)<br># Alternative: A.shape = (1,9) <br>#
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to change the array in place<br><br><font color="#ff420e"><font size="2" style="font-size: 10pt"><b>P></b></font></font>
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total_elements = np.prod(A.shape)</font></font></p>
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<p align="left"><font face="Andale Mono"><font size="1" style="font-size: 8pt"><font color="#ff420e"><font size="2" style="font-size: 10pt"><b>P></b></font></font>
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B = A.reshape(1, total_elements) <br><br># alternative
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shortcut:<br># A.reshape(1,-1)<br><br><font color="#ff420e"><font size="2" style="font-size: 10pt"><b>P></b></font></font>
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B<br>array([[1, 2, 3, 4, 5, 6, 7, 8, 9]])</font></font></p>
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</td>
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<td bgcolor="#ffffff" style="border-top: none; border-bottom: none; border-left: 1px dotted #000000; border-right: 1px dotted #000000; padding: 0in 0.02in">
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@ -885,9 +900,9 @@ Bezanson, J., Karpinski, S., Shah, V.B. and Edelman, A. (2012), “Julia: A fast
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</td>
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</tr>
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<tr>
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<td colspan="6" height="114" bgcolor="#ffffff" style="border: none; padding: 0in" id='basic_ops'>
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<td colspan="6" height="114" bgcolor="#ffffff" style="border: none; padding: 0in">
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<p align="center"><font face="Arial"><font size="4" style="font-size: 14pt"><b>BASIC
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MATRIX OPERATIONS</b></font></font><br>[<a href='#cheat_overview'>back to cheat sheet overview</a>]</p>
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MATRIX OPERATIONS</b></font></font></p>
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</td>
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</tr>
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<tr valign="top">
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@ -912,6 +927,9 @@ Bezanson, J., Karpinski, S., Shah, V.B. and Edelman, A. (2012), “Julia: A fast
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A + 2<br><br><font color="#ff420e"><font size="2" style="font-size: 10pt"><b>P></b></font></font>
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A - 2<br><br><font color="#ff420e"><font size="2" style="font-size: 10pt"><b>P></b></font></font>
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A / 2</font></font></p>
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<p align="left"><font face="Andale Mono"><font size="1" style="font-size: 8pt">#
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Note that NumPy was optimized for<br># in-place assignments<br>#
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e.g., A += A instead of <br># A = A + A</font></font></p>
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</td>
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<td bgcolor="#cfe7f5" style="border-top: none; border-bottom: none; border-left: 1px dotted #000000; border-right: 1px dotted #000000; padding: 0in 0.02in">
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<p align="left"><font face="Andale Mono"><font size="1" style="font-size: 8pt"><font color="#0000ff"><font size="2" style="font-size: 10pt"><b>R></b></font></font>
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@ -1025,6 +1043,9 @@ Bezanson, J., Karpinski, S., Shah, V.B. and Edelman, A. (2012), “Julia: A fast
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A + A<br><br><font color="#ff420e"><font size="2" style="font-size: 10pt"><b>P></b></font></font>
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A - A<br><br><font color="#ff420e"><font size="2" style="font-size: 10pt"><b>P></b></font></font>
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A / A</font></font></p>
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<p align="left"><font face="Andale Mono"><font size="1" style="font-size: 8pt">#
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Note that NumPy was optimized for<br># in-place assignments<br>#
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e.g., A += A instead of <br># A = A + A</font></font></p>
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</td>
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<td bgcolor="#ffffff" style="border-top: none; border-bottom: none; border-left: 1px dotted #000000; border-right: 1px dotted #000000; padding: 0in 0.02in">
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<p align="left"><font face="Andale Mono"><font size="1" style="font-size: 8pt"><font color="#0000ff"><font size="2" style="font-size: 10pt"><b>R></b></font></font>
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@ -1232,9 +1253,9 @@ Bezanson, J., Karpinski, S., Shah, V.B. and Edelman, A. (2012), “Julia: A fast
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</td>
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</tr>
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<tr>
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<td colspan="6" height="202" bgcolor="#ffffff" style="border: none; padding: 0in" id='advanced_ops'>
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<td colspan="6" height="202" bgcolor="#ffffff" style="border: none; padding: 0in">
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<p align="center"><font face="Arial"><font size="4" style="font-size: 14pt"><b>ADVANCED
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MATRIX OPERATIONS</b></font></font><br>[<a href='#cheat_overview'>back to cheat sheet overview</a>]</p>
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MATRIX OPERATIONS</b></font></font></p>
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</td>
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</tr>
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<tr valign="top">
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@ -1328,7 +1349,7 @@ Bezanson, J., Karpinski, S., Shah, V.B. and Edelman, A. (2012), “Julia: A fast
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</td>
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</tr>
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<tr valign="top">
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<td height="539" bgcolor="#ffffff" style="border-top: none; border-bottom: none; border-left: none; border-right: 1px solid #000000; padding-top: 0in; padding-bottom: 0in; padding-left: 0in; padding-right: 0.02in">
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<p align="left"><font face="Arial"><font size="2" style="font-size: 10pt"><b>Generating
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a Gaussian dataset:<br><br>creating random vectors from the
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multivariate normal<br>distribution given mean and covariance
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@ -1395,6 +1416,8 @@ Bezanson, J., Karpinski, S., Shah, V.B. and Edelman, A. (2012), “Julia: A fast
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</td>
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</tr>
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</table>
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<br>
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<br><br><font size=0.6>
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<title></title>
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<meta name="generator" content="LibreOffice 4.2.4.2 (MacOSX)">
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<td height="58" bgcolor="#0066cc" style="border: none; padding: 0in">
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<td height="59" bgcolor="#0066cc" style="border: none; padding: 0in">
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<p align="center"><font color="#ffffff"><font face="Arial"><font size="5" style="font-size: 18pt"><b>Task</b></font></font></font></p>
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</td>
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<td bgcolor="#0066cc" style="border: none; padding: 0in">
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@ -92,12 +92,12 @@
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3</font></font></p>
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</td>
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<td bgcolor="#cfe7f5" style="border-top: none; border-bottom: none; border-left: 1px dotted #000000; border-right: 1px dotted #000000; padding: 0in 0.02in">
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<p align="left"><font color="#ff420e"><font face="Andale Mono"><font size="2" style="font-size: 10pt"><b>P></b></font></font></font><font face="Andale Mono"><font size="1" style="font-size: 8pt">
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</font></font><font face="Andale Mono"><font size="1" style="font-size: 8pt">a</font></font><font color="#2fff12"><font face="AndaleMono, serif"><font size="4" style="font-size: 14pt">
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</font></font></font><font color="#000000"><font face="Andale Mono"><font size="1" style="font-size: 8pt">=
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<p align="left"><font color="#ff420e"><font face="Andale Mono"><font size="2" style="font-size: 10pt"><b>P></b></font></font></font>
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<font face="Andale Mono"><font size="1" style="font-size: 8pt">a</font></font><font color="#2fff12">
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</font><font color="#000000"><font face="Andale Mono"><font size="1" style="font-size: 8pt">=
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np.array([1,2,3]).reshape(1,3)</font></font></font></p>
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<p align="left"><font face="Andale Mono"><font size="1" style="font-size: 8pt"><br></font></font><font color="#ff420e"><font face="Andale Mono"><font size="2" style="font-size: 10pt"><b>P></b></font></font></font><font face="Andale Mono"><font size="1" style="font-size: 8pt">
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</font></font><font color="#000000"><font face="Andale Mono"><font size="1" style="font-size: 8pt">b.shape<br>(1,
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<p align="left"><font face="Andale Mono"><font size="1" style="font-size: 8pt"><br></font></font><font color="#ff420e"><font face="Andale Mono"><font size="2" style="font-size: 10pt"><b>P></b></font></font></font>
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<font color="#000000"><font face="Andale Mono"><font size="1" style="font-size: 8pt">b.shape<br>(1,
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3)</font></font></font></p>
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<p align="left"><br>
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</p>
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@ -132,10 +132,10 @@
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<p align="left"><font face="Andale Mono"><font size="1" style="font-size: 8pt">#
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note that numpy doesn't have <br># explicit “row-vectors”, but
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1-D <br># arrays</font></font></p>
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<p style="margin-bottom: 0in"><font face="Liberation Serif, serif"><font size="3" style="font-size: 12pt"><font color="#ff420e"><font face="Andale Mono"><font size="2" style="font-size: 10pt"><b>P></b></font></font></font><font color="#2fff12"><font face="AndaleMono, serif"><font size="4" style="font-size: 14pt"><b>
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</b></font></font></font><font color="#000000"><font face="Andale Mono"><font size="1" style="font-size: 8pt">b.shape</font></font></font></font></font></p>
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<p style="margin-bottom: 0in"><font face="Liberation Serif, serif"><font size="3" style="font-size: 12pt"><font color="#ff420e"><font face="Andale Mono"><font size="2" style="font-size: 10pt"><b>P></b></font></font></font><font color="#2fff12">
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</font><font color="#000000"><font face="Andale Mono"><font size="1" style="font-size: 8pt">b.shape</font></font></font></font></font></p>
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<p style="margin-bottom: 0in"><font face="Andale Mono"><font size="1" style="font-size: 8pt">(3,)</font></font></p>
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<p align="left"><font face="Andale Mono"><font size="1" style="font-size: 8pt"><br></font></font><br>
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<p align="left"><br>
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</p>
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</td>
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<td bgcolor="#ffffff" style="border-top: none; border-bottom: none; border-left: 1px dotted #000000; border-right: 1px dotted #000000; padding: 0in 0.02in">
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@ -704,6 +704,9 @@
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A + 2<br><br><font color="#ff420e"><font size="2" style="font-size: 10pt"><b>P></b></font></font>
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A - 2<br><br><font color="#ff420e"><font size="2" style="font-size: 10pt"><b>P></b></font></font>
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A / 2</font></font></p>
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<p align="left"><font face="Andale Mono"><font size="1" style="font-size: 8pt">#
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Note that NumPy was optimized for<br># in-place assignments<br>#
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e.g., A += A instead of <br># A = A + A</font></font></p>
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</td>
|
||||
<td bgcolor="#cfe7f5" style="border-top: none; border-bottom: none; border-left: 1px dotted #000000; border-right: 1px dotted #000000; padding: 0in 0.02in">
|
||||
<p align="left"><font face="Andale Mono"><font size="1" style="font-size: 8pt"><font color="#0000ff"><font size="2" style="font-size: 10pt"><b>R></b></font></font>
|
||||
|
|
@ -817,6 +820,9 @@
|
|||
A + A<br><br><font color="#ff420e"><font size="2" style="font-size: 10pt"><b>P></b></font></font>
|
||||
A - A<br><br><font color="#ff420e"><font size="2" style="font-size: 10pt"><b>P></b></font></font>
|
||||
A / A</font></font></p>
|
||||
<p align="left"><font face="Andale Mono"><font size="1" style="font-size: 8pt">#
|
||||
Note that NumPy was optimized for<br># in-place assignments<br>#
|
||||
e.g., A += A instead of <br># A = A + A</font></font></p>
|
||||
</td>
|
||||
<td bgcolor="#ffffff" style="border-top: none; border-bottom: none; border-left: 1px dotted #000000; border-right: 1px dotted #000000; padding: 0in 0.02in">
|
||||
<p align="left"><font face="Andale Mono"><font size="1" style="font-size: 8pt"><font color="#0000ff"><font size="2" style="font-size: 10pt"><b>R></b></font></font>
|
||||
|
|
@ -1120,7 +1126,7 @@
|
|||
</td>
|
||||
</tr>
|
||||
<tr valign="top">
|
||||
<td height="540" bgcolor="#ffffff" style="border-top: none; border-bottom: none; border-left: none; border-right: 1px solid #000000; padding-top: 0in; padding-bottom: 0in; padding-left: 0in; padding-right: 0.02in">
|
||||
<td height="541" bgcolor="#ffffff" style="border-top: none; border-bottom: none; border-left: none; border-right: 1px solid #000000; padding-top: 0in; padding-bottom: 0in; padding-left: 0in; padding-right: 0.02in">
|
||||
<p align="left"><font face="Arial"><font size="2" style="font-size: 10pt"><b>Generating
|
||||
a Gaussian dataset:<br><br>creating random vectors from the
|
||||
multivariate normal<br>distribution given mean and covariance
|
||||
|
|
|
|||
Loading…
Reference in New Issue
Block a user