Eigen 输出格式

Eigen::IOFormat Class Reference

Detailed Description

Stores a set of parameters controlling the way matrices are printed.

List of available parameters:

• precision number of digits for floating point values, or one of the special constantsStreamPrecision andFullPrecision. The default is the special valueStreamPrecision which means to use the stream's own precision setting, as set for instance usingcout.precision(3). The other special valueFullPrecision means that the number of digits will be computed to match the full precision of each floating-point type.精度
• flags an OR-ed combination of flags, the default value is 0, the only currently available flag isDontAlignCols which allows to disable the alignment of columns, resulting in faster code.设置标号
• coeffSeparator string printed between two coefficients of the same row同一行两个数的分隔符
• rowSeparator string printed between two rows 两行之间的分隔符
• rowPrefix string printed at the beginning of each row每一行开头符号
• rowSuffix string printed at the end of each row每一行结束符号
• matPrefix string printed at the beginning of the matrix矩阵开始时符号
• matSuffix string printed at the end of the matrix矩阵结束时符号

Example:

std::string sep = "\n----------------------------------------\n";

Matrix3d m1;

m1 << 1.111111, 2, 3.33333, 4, 5, 6, 7, 8.888888, 9;

IOFormat CommaInitFmt(StreamPrecision, DontAlignCols,", ",", ","", "", " << ", ";");

IOFormat CleanFmt(4, 0,", ","\n","[", "]");

IOFormat OctaveFmt(StreamPrecision, 0,", ",";\n","", "", "[", "]");

IOFormat HeavyFmt(FullPrecision, 0,", ",";\n","[", "]", "[", "]");

std::cout << m1 << sep;

std::cout << m1.format(CommaInitFmt) << sep;

std::cout << m1.format(CleanFmt) << sep;

std::cout << m1.format(OctaveFmt) << sep;

std::cout << m1.format(HeavyFmt) << sep;

Output:

1.11    2 3.33   4    5    6   7 8.89    9---------------------------------------- << 1.11, 2, 3.33, 4, 5, 6, 7, 8.89, 9;----------------------------------------[1.111,     2, 3.333][    4,     5,     6][    7, 8.889,     9]----------------------------------------[1.11,    2, 3.33;    4,    5,    6;    7, 8.89,    9]----------------------------------------[[1.111111,        2,  3.33333]; [       4,        5,        6]; [       7, 8.888888,        9]]----------------------------------------