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<div><h1>mutable matrices</h1>
<div>To and from matrices:<table class="examples"><tr><td><pre>i1 : m = matrix{{1,2,3},{4,5,6}}
o1 = | 1 2 3 |
| 4 5 6 |
2 3
o1 : Matrix ZZ <--- ZZ</pre>
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<tr><td><pre>i2 : n = mutableMatrix m
o2 = | 1 2 3 |
| 4 5 6 |
o2 : MutableMatrix</pre>
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<tr><td><pre>i3 : m2 = matrix n
o3 = | 1 2 3 |
| 4 5 6 |
2 3
o3 : Matrix ZZ <--- ZZ</pre>
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<tr><td><pre>i4 : m2 - m == 0
o4 = true</pre>
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Modifying and accessing entries. Remember that the upper left entry is (0,0), not (1,1)!<table class="examples"><tr><td><pre>i5 : n_(0,0) = 212314323
o5 = 212314323</pre>
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<tr><td><pre>i6 : n_(0,0)
o6 = 212314323</pre>
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<tr><td><pre>i7 : n
o7 = | 212314323 2 3 |
| 4 5 6 |
o7 : MutableMatrix</pre>
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Number of rows, columns, and the ring:<table class="examples"><tr><td><pre>i8 : numrows n
o8 = 2</pre>
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<tr><td><pre>i9 : numColumns n
o9 = 3</pre>
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<tr><td><pre>i10 : numcols n
o10 = 3</pre>
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<tr><td><pre>i11 : ring n
o11 = ZZ
o11 : Ring</pre>
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<p/>
<a href="_row_spand_spcolumn_spoperations.html" title="">row and column operations</a><p/>
Some other methods for creating mutable matrices.<table class="examples"><tr><td><pre>i12 : mutableIdentity(RR_100,5)
o12 = | 1 . . . . |
| . 1 . . . |
| . . 1 . . |
| . . . 1 . |
| . . . . 1 |
o12 : MutableMatrix</pre>
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<tr><td><pre>i13 : mutableMatrix(QQ,3,5)
o13 = 0
o13 : MutableMatrix</pre>
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<tr><td><pre>i14 : randomMutableMatrix(4,4,.5,100)
o14 = | . . 68 29 |
| -81 . . . |
| . . 90 -68 |
| -63 . 95 . |
o14 : MutableMatrix</pre>
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