wehub-resource-sync
62 lines
1.1 KiB
Markdown
62 lines
1.1 KiB
Markdown
## Simple
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This example simply performs a matrix multiplication, solely for the purpose of demonstrating a basic usage of ggml and backend handling. The code is commented to help understand what each part does.
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Traditional matrix multiplication goes like this (multiply row-by-column):
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$$
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A \times B = C
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$$
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$$
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\begin{bmatrix}
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2 & 8 \\
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5 & 1 \\
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4 & 2 \\
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8 & 6 \\
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\end{bmatrix}
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\times
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\begin{bmatrix}
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10 & 9 & 5 \\
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5 & 9 & 4 \\
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\end{bmatrix}
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\=
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\begin{bmatrix}
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60 & 90 & 42 \\
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55 & 54 & 29 \\
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50 & 54 & 28 \\
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110 & 126 & 64 \\
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\end{bmatrix}
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$$
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In `ggml`, we pass the matrix $B$ in transposed form and multiply row-by-row. The result $C$ is also transposed:
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$$
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ggml\\_mul\\_mat(A, B^T) = C^T
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$$
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$$
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ggml\\_mul\\_mat(
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\begin{bmatrix}
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2 & 8 \\
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5 & 1 \\
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4 & 2 \\
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8 & 6 \\
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\end{bmatrix}
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,
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\begin{bmatrix}
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10 & 5 \\
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9 & 9 \\
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5 & 4 \\
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\end{bmatrix}
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)
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\=
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\begin{bmatrix}
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60 & 55 & 50 & 110 \\
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90 & 54 & 54 & 126 \\
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42 & 29 & 28 & 64 \\
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\end{bmatrix}
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$$
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The `simple-ctx` doesn't support gpu acceleration. `simple-backend` demonstrates how to use other backends like CUDA and Metal.
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