C/Java/Python 中的 %.4f 格式化代码详解

This is a formatting code used in programming languages such as C, Java, and Python to format numeric values as a string.

The '-8' specifies the minimum width of the output, including any decimal points and negative signs. If the value is shorter than 8 characters, it will be padded with spaces on the left.

The '4' specifies the number of digits after the decimal point.

The 'f' indicates that the value is a floating-point number.

For example, if we have a floating-point number 3.14159265359 and we apply the format code '%.4f', the output will be '3.1416'. If we apply the format code '%-8.4f', the output will be '3.1416 ', with two spaces at the end to pad the number to a width of 8 characters.