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Update README.md

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Signed-off-by: David Rotermund <54365609+davrot@users.noreply.github.com>
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David Rotermund 2024-01-02 17:36:35 +01:00 committed by GitHub
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numpy/einstein/README.md
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@ -22,6 +22,8 @@ print(a)
print(a.shape) # -> (5, 5)
print(np.einsum("ii", a)) # -> 60
print(np.einsum(a, [0, 0])) # -> 60
print(np.einsum(a, [0, 0], [])) # -> 60
```
Output:
@ -41,6 +43,7 @@ import numpy as np
a = np.arange(0, 25).reshape(5, 5)
print(np.einsum("ii->i", a)) # -> [ 0 6 12 18 24]
print(np.einsum(a, [0, 0], [0])) # -> [ 0 6 12 18 24]
```
$$b(i) = \sum_j a_{i,j}$$
@ -50,6 +53,7 @@ import numpy as np
a = np.arange(0, 25).reshape(5, 5)
print(np.einsum("ij->i", a)) # -> [ 10 35 60 85 110]
print(np.einsum(a, [0, 1], [0])) # -> [ 10 35 60 85 110]
print(np.einsum("...j->...", a)) # -> [ 10 35 60 85 110]
```
@ -62,6 +66,8 @@ a = np.arange(0, 25).reshape(5, 5)
print(a)
print()
print(np.einsum("ij->ji", a))
print()
print(np.einsum(a, [0, 1], [1, 0]))
```
Output:
@ -73,6 +79,12 @@ Output:
[15 16 17 18 19]
[20 21 22 23 24]]
[[ 0 5 10 15 20]
[ 1 6 11 16 21]
[ 2 7 12 17 22]
[ 3 8 13 18 23]
[ 4 9 14 19 24]]
[[ 0 5 10 15 20]
[ 1 6 11 16 21]
[ 2 7 12 17 22]
@ -88,6 +100,8 @@ import numpy as np
a = np.arange(0, 5)
print(a) # -> [0 1 2 3 4]
print(np.einsum("i,i", a, a)) # -> 30
print(np.einsum(a, [0], a, [0])) # -> 30
print(np.einsum(a, [0], a, [0], [])) # -> 30
```
$$c(i) = \sum_j a_{i,j} b_j$$
@ -102,6 +116,8 @@ print(a)
print()
print(b) # -> [0 1 2 3 4]
print(np.einsum("ij,j", a, b)) # -> [ 30 80 130 180 230]
print(np.einsum(a, [0, 1], b, [1])) # -> [ 30 80 130 180 230]
print(np.einsum(a, [0, 1], b, [1], [0])) # -> [ 30 80 130 180 230]
```
```python