一、What is' from buffer '

In the Python language, the from buffer () function is used to convert the contents of a buffer or array into a new Python object. According to the official document definition, the "from buffer (buffer, dtype=float, count=-1, offset=0)" function can read data from a given buffer and convert it to a Python object according to the specified data type to return.

That is to say, the frombruffer() function can create a new Python object whose data comes from a given buffer (such as a byte array, string).

二、How to use 'from buffer'

The frombruffer() function is a function in the numpy module, and the numpy module needs to be introduced first:

Then, use the frombruffer() function in the following way:

The specific parameters are explained as follows:

buffer：The buffer or array that needs to be converted.

dtype：The converted data type, if not specified, defaults to 'float'。

count：The amount of data that needs to be read, if not specified, defaults to -1, which means reading the entire buffer.

offset：The offset for reading data, which defaults to 0.

三、Example of from buffer

The following is a simple example to demonstrate how to use the frombruffer() function:

Executing the above code yields the following results：

Here, we first define the buffer as a byte array of 'hello world'. Then we use the frombruffer() function to convert the byte array into a numpy array new_ Array and specify the data type as string, with each character having a separate byte (i.e. "S1"). Finally, we output the values of the new array.

四、Precautions for from buffer

Although the frombruffer() function is very flexible and efficient, it is also important to pay attention to the following points when using it:

Buffer or array should be contiguous memory blocks。

The data type in the buffer should be a valid numpy data type。

If the length of the buffer is not sufficient to store a specific amount of data, an exception will be thrown。

五、Extended usage of 'from buffer'

In practical applications, the frombruffer() function has some special uses. For example, the from buffer () function can be used to convert byte data in the buffer into Python objects.

The following code demonstrates how to convert byte data in a buffer into Python objects:

Execute the above code, and the output result is:

Here, we have created a byte array and converted it into a Python object new using the frombruffer() function_ Obj. Due to the use of an unsigned 8-bit integer (uint8) data type, the values for the new object are 1, 2, 3, 4, and 5.

This article starts with what "from buffer" is and analyzes the usage methods, examples, usage precautions, and extended usage of "from buffer" one by one. For Python developers who use the numpy module for data processing, it is essential to have a knowledge of the from buffer function.