< [[Main Page]] | moved to [[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 with {{cmd|startalign}} == <context source=yes>\startformula\startalign \NC v \NC = u + at \NR \NC h \NC = ut + \frac12 gt^2 \NR\stopalign\stopformula</context> == 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> <context source=yes>\startformula \startalign[n=3] \NC v \NC = u \NC+ at \NR \NC h \NC = ut \NC+ \frac12 gt^2 \NR\stopalign \stopformula</context> == 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 <context source=yes>\startformula \startalign[n=3,align={1:right,2:middle,3:left}] \NC v \NC = u \NC+ at \NR \NC h \NC= ut \NC+ \frac12 gt^2 \NR\stopalign \stopformula</context> This mechanism allows fancier alignments like <context source=yes>\startformula \startalign[n=4,align={1:right,2:right,3:middle,4:left}] \NC \text{We have} \quad \NC v \NC = u \NC+ at \NR \NC \text{and} \quad \NC h \NC= ut \NC+ \frac12 gt^2 \NR\stopalign \stopformula</context> == Working with equation numbering == aligned equations can be numbered by using {{cmd|startplaceformula}} (as usual), and by placing a tag after {{cmd|NR}} <context source=yes>\setuplayout[scale=0.8,width=13cm]\startplaceformula\startformula \startalign \NC v \NC = u + at \NR[eq:v] \NC h \NC = ut + \frac12 gt^2 \NR[eq:h]\stopalign \stopformula \stopplaceformulaEquation~(\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]\startplaceformula\startformula \startalign \NC v \NC = u + at \NR[+][eq:v] \NC h \NC = ut + \frac12 gt^2 \NR[+][eq:h]\stopalign \stopformula\stopplaceformula 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={1: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\delta_{ij} = \startmathcases \NC 1 \NC \text{if } i = j \NR \NC 0 \NC \text{otherwise} \NR \stopmathcases\stopformula</context> The cases environment consists of two columns, separated by {{cmd|NC}}. The second column is by default in math mode. To typeset the second column in text mode, use {{cmd|TC}} <texcode>\startformula\delta_{ij} = \startmathcases \NC 1 \TC if \m{i = j} \NR \NC 0 \TC otherwise \NR \stopmathcases\stopformula</texcode> Each line must end with a {{cmd|NR}}. == Numbered Cases == [[Category:MathMultiline_equations]]