8
edits
Changes
Jump to navigation
Jump to search
m
<texcode>
\startformula \startalign
v &= u + at \\
h &= ut + \frac12 gt^2 \\
\stopalign \stopformula
</texcode>
Add ties (non-breaking spaces) before equation numbers and variable names.
< [[Main Page]] | [[Math]] | [[Math with newmat]] | [[MathML]] >
Be sure to also read [http://dl.contextgarden.net/myway/mathalign.pdf Using \startalign and friends] written by Aditya Mahajan.
== Basic Alignment ==
* Latex style
<context source=yes text="Note the \\ in the last line , above. This appears as follows<context:">
\startformula \startalign
v &= u + at \\
</context>
* Context Stlye <texcode>\startformula \startalign \NC v \NC = u + at \NR \NC h \NC= ut + \frac12 gt^2 \NR\stopalign \stopformula</texcode>Style
<contextsource=yes>
\startformula \startalign
\NC v \NC = u + at \NR
\NC h \NC= ut + \frac12 gt^2 \NR
\stopalign \stopformula
</context>
( The examples here will focus on the context style, having two styles can be confusing --[[User:Adityam| Aditya ]] )
== Changing the number of columns ==
The above equations were aligned at <code>=</code>. Suppose you also want the <code>+</code> to align. Well, this is simple in context, simply specify the number of columns with <code>\startalign</code>
<texcode>\startformula \startalign[n=3] \NC v \NC = u \NC+ at \NR \NC h \NCcontext source= ut \NC+ \frac12 gt^2 \NR\stopalign \stopformula</texcode> <contextyes>
\startformula \startalign[n=3]
\NC v \NC = u \NC+ at \NR
== Alignment of each column ==
If you want more control over the formatting, and want the middle column to be center aligned, you can do that by
<texcodecontext source=yes>
\startformula \startalign[n=3,align={right,middle,left}]
\NC v \NC = u \NC+ at \NR
\NC h \NC= ut \NC+ \frac12 gt^2 \NR
\stopalign \stopformula
</texcodecontext> This mechanism allows fancier alignments like
<contextsource=yes>\startformula \startalign[n=34,align={left,right,middle,left}] \NC \text{We have} \quad \NC v \NC = u \NC+ at \NR \NC \text{and} \NC h \NC= ut \NC+ \frac12 gt^2 \NR
\stopalign \stopformula
</context>
== Working with equation numbering ==
aligned equations can be numbered by placing a tag after {{cmd|NR}}
<context source=yes>
\setuplayout[scale=0.8,width=13cm]
\placeformula \startformula \startalign
\NC v \NC = u + at \NR[eq:v]
\NC h \NC = ut + \frac12 gt^2 \NR[eq:h]
\stopalign \stopformula
Equation~(\in[eq:v]) tells the final velocity after time~$t$ and equation~(\in[eq:h]) tells the distance travelled in time~$t$.
</context>
The numbering can be changed to a subformula style using {{cmd|placesubformula}} instead of {{cmd|placeformula}} and numbering the subformulas using {{cmd|NR|2=[+][a]}}, {{cmd|NR|2=[+][b]}}, … instead:
<context source=yes>
\setuplayout[scale=0.8,width=13cm]
\placesubformula \startformula \startalign
\NC v \NC = u + at \NR[+][eq:v]
\NC h \NC = ut + \frac12 gt^2 \NR[+][eq:h]
\stopalign \stopformula
Equation~(\in[eq:v]) tells the final velocity after time~$t$ and equation (\in[eq:h]) tells the distance travelled in time~$t$.
</context>
== Changing the number of columns ==
== Defining new alignment structures ==
New alignment can be defined using {{cmd|definemathalignment}}. For example, to emulate <code>gather</code> environment of amsmath, we can use
<context source=yes>
\definemathalignment
[gather]
[n=1,align={middle}]
\startformula \startgather
\NC ax^2 + bx + c = 0 \NR
\NC \text{roots} = \frac{ -b \pm \sqrt{b^2 - 4ac}}{2a} \NR
\stopgather \stopformula
</context>
== Cases ==
Context provides a {{cmd|startmathcases}} {{cmd|stopmathcases}} pair to make it easy to get cases.
<context source=yes text="gives">
\startformula
f(x) = \startmathcases
\NC x, \NC if $0 \le x \le \frac12$ \NR
\NC 1-x ,\NC if $\frac12 \le x \le 1$ \NR
\stopmathcases
\stopformula
</context>
The cases environment consists of two columns, separated by {{cmd|NC}}. The second column is by default in text mode. An alternative way of getting the same result is to define the second column as a mathcolumn with {{cmd|MC}} like so:
<texcode>
\startformula
f(x) = \startmathcases
\NC x, \MC \text{if } 0 \le x \le \frac12 \NR
\NC 1-x ,\MC \text{if } \frac12 \le x \le 1 \NR
\stopmathcases
\stopformula
</texcode>
Each line must end with a {{cmd|NR}}.
== Numbered Cases ==
[[Category:Math]]
