Added dot.md

content/numpy/concepts/ndarray/terms/dot/dot.md

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+---
+Title: '.dot()'
+Description: 'Computes the dot product of two arrays.'
+Subjects:
+  - 'Code Foundations'
+  - 'Computer Science'
+Tags:
+  - 'Arrays'
+  - 'Linear Algebra'
+  - 'Methods'
+  - 'NumPy'
+CatalogContent:
+  - 'learn-python-3'
+  - 'paths/computer-science'
+---
+
+The **`.dot()`** method computes the dot product of an array with another array or scalar. For one-dimensional arrays, it calculates the standard inner product of vectors. When applied to two-dimensional arrays, it performs matrix multiplication. For arrays with higher dimensions, it executes a sum-product over the last axis of the first array and the second-to-last axis of the second array.
+
+## Syntax
+
+```pseudo
+ndarray.dot(b, out=None)
+```
+
+**Parameters:**
+
+- `ndarray`: The first array (A) in the dot product operation (A $\cdot$ B).
+- `b`: The second array (B) or scalar in the dot product operation.
+- `out` (optional): An alternative output array to place the result in. It must have the same shape and buffer length as the expected output, but the type will be cast if necessary.
+
+**Return value:**
+
+Returns the dot product as a scalar, 2-D array, or ndarray, depending on the input dimensions.
+
+## Example
+
+This example shows how to use the `.dot()` method for matrix multiplication between two 2D NumPy arrays, `matrix_a` and `matrix_b`:
+
+```py
+# Import NumPy
+import numpy as np
+
+# Create the first 2x3 matrix
+matrix_a = np.array([[1, 2, 3],
+                     [4, 5, 6]])
+
+# Create the second 3x2 matrix
+matrix_b = np.array([[7, 8],
+                     [9, 10],
+                     [11, 12]])
+
+# Use the '.dot()' method for matrix multiplication (2x3 @ 3x2 = 2x2)
+result_matrix = matrix_a.dot(matrix_b)
+
+print("Matrix A:")
+print(matrix_a)
+print("\nMatrix B:")
+print(matrix_b)
+print("\nResult (A.dot(B)):")
+print(result_matrix)
+```
+
+The output of the above code will be:
+
+```shell
+Matrix A:
+[[1 2 3]
+ [4 5 6]]
+
+Matrix B:
+[[ 7  8]
+ [ 9 10]
+ [11 12]]
+
+Result (A.dot(B)):
+[[ 58  64]
+ [139 154]]
+```
+
+## Codebyte Example
+
+In the following codebyte example, the `.dot()` method is used to calculate the inner product (dot product) of two one-dimensional vectors, `vector_x` and `vector_y`:
+
+```codebyte/python
+import numpy as np
+
+# Create two 1-D arrays (vectors)
+vector_x = np.array([1, 2, 3])
+vector_y = np.array([5, 6, 7])
+
+# Calculate the inner product (dot product)
+dot_product = vector_x.dot(vector_y)
+
+print(f"Vector x: {vector_x}")
+print(f"Vector y: {vector_y}")
+print(f"Dot product (x.dot(y)): {dot_product}")
+```
+
+Calculation breakdown:
+
+$$\vec{x} \cdot \vec{y} = (1 \times 5) + (2 \times 6) + (3 \times 7) = 5 + 12 + 21 = 38$$