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1. Sorting units
In the textbook or report, the interlinear formula is sorted by chapter, that is, at the beginning of each new chapter, the formula serial number counterequation is zeroed out. For example, Chapter 1, the third formula of the serial number is (1.3), Chapter 2, the first formula of the serial number is (2.1). A number of sections in a chapter, if there are many formulas in each section, this sorting is difficult to distinguish a formula belongs to which section. If you want the formula can be sorted by section, you can add the formula macro package in the introduction to provide the sorting unit command: \numberwithin{equation}{section}
This adds the section serial number to the serial number of all formulas. For example, chapter 1, section 3, the second formula serial number is: (1.3.2). In the article in the text category, the formula between the lines of the serial number is to the full text as the unit of order, if you want to change to the section as the unit of order, you can also use the above order unit command.
2. Cancellation and substitution
With an asterisk formula environment, as well as the splits and cases formula environment will not give the formula serial number, the other formula environment without the model can automatically provide the formula serial number. However, sometimes I hope that some formulas in the formula group has a serial number, some do not have, some have to mark another, it is necessary to use the following serial number setting commands.
| \eqno{marker} | The system provides a serial number setting command, it will be immediately after the equation * environment or \ [...\] form of the formula line, you can manually set the label on the right side of the formula. The label can be any text |
| \leqno{marker} | The effect is the same as \eqno, except that the sign is to the left of the formula. \eqno and \leqno can not be used in a formula at the same time |
| \nonumber | The system provides a command to cancel the serial number. Insert it before the line feed command \\, you can cancel the formula for the line to be sorted so that it has no serial number |
| \notag | The formula macro package provides the serial number cancel command, which is used in the same way as the \nonumber command. |
| \tag{label} | The formula macro package provides a serial number setting command that, when inserted before the line feed command \\, unsorts the formula for the line and replaces the serial number with (mark). This command can also be used in formula lines in asterisked formula environments to give them a (marker) |
| \tag*{marker} | The function is the same as \tag, except that there are no parentheses on either side of the tag. |
2.1 Change the ordinal numbering of matrix equations to manual labeling and place it to the left side of the equation
Code:
$$\left(\begin{array}{lcr}
a_{11}& a_{12} & a_{13}\\
a_{21} & a_{22} & a_{23}
\end{array}\right)=0 \leqno[A.1] $$
The obtained formula is as follows:
2.3 Use a different style of ordinal numbering and labeling for each equation in the system of equations
Using the cross-reference commands \label and \ref to generate sub-serial numbers
Code:
\begin{gather}
x^2+y^2=z^2 \label{eq:r2} \\
x^3+y^3=z^3 \notag \\
x^4+y^4=z^4 \tag{$*$} \\
x^5+y^5=z^5 \tag*{$*$} \\
x^6+y^6=z^6 \tag{\ref{eq:r2}$'$}
\end{gather}
The obtained formula is as follows:
2.4 Using the Cancel Sequence Command to Arrange Multi-Line Formulas in a Formula Group Environment
Code:
\begin{align}
f(t)=& e^{-t}(\sin2t + 2\sin4t -{}\nonumber\\
& {}- 0.4\sin2t\sin40t)
\end{align}
The formula obtained:
If you remove the command \nonumber to cancel the serial number
Code:
\begin{align}
f(t)=& e^{-t}(\sin2t + 2\sin4t -{}\\
& {}- 0.4\sin2t\sin40t)
\end{align}
The resulting formula is as follows (look carefully at the numbering):
3 Bottom serial number
Usually the serial number of the multi-line formula is centered vertically, in order to put the serial number to the end of the last line, you can add a top serial number in the formula macro package of the call command to select a good, that is, \usepackage[tbtags]{amsmath}, you can put the serial number of the Charley's multi-line formula in the end of the line at the end of the right end.
Code:
\begin{equation}
\begin{split}
f(x) & = 2(x+1)^{2} -1 \\
& = 2(x^{2}+2x+1)-1 \\
& = 2x^{2} + 4x + 1
\end{split}
\end{equation}
The formula obtained:
