Mathematical equation  %eq[equation]
%eq is provided to enable mathematical equations to be drawn. It is followed by
a standard character string (i.e. a string in square brackets, or an '@'
symbol with a string as an argument). It takes two integer arguments which are
the width and depth of the equation in pixels. If the contents of the equation
are not going to change, then the width and depth are set to zero, forcing the
size of the region to be defined by the equation. Equations may also be
included in hypertext (see Hypertext windows).
Equations are strings with the three characters {;} reserved. The following
symbols can be included in strings:
{alpha}

{beta}

{gamma}

{delta}

{epsilon}

{phi}

{pi}

{zeta}

{psi}

{sigma}

{theta}

{kappa}

{lambda}

{iota}

{rho}

{mu}

{nu}

{omega}

{chi}

{tau}

{infinity}

{plus_minus}

{ge}

{proportional}

{curly_d}

{le}

{ne}

{identically_eq}

{approximately_eq}

{such_that}

{vector_sum}

{empty_set}

{set_intersection}

{set_union}

{proper_subset}

{subset}

{belongs_to}

{not_belongs_to}

{for_all}

{there_exists}

{del}

{sqrt}

{semicolon}


The names of these special symbols are case sensitive, and the Greek characters
also exist as upper case characters. In this context only the first character
is upper case.
In addition, a number of more complex constructions are supplied. In the list
below , the asterisk "*" stands for any equation string:
{sup *}

Superscript or exponent

{sub *}

Subscript

{divide *;*}

Division written with a horizontal bar

{sum *}

Summation without upper limit

{sum *;*}

Summation with both limits

{integral }

Indefinite integral

{integral *}

Integral with lower limit only

(integral *;*}

Full definite integral.

{symbol nnn}

Character number nnn (decimal) from the symbol font.

Note that the body of the sum or integral will be placed after the closing curly
brace. Spaces are important in the above constructions.
Badly formed equations will normally cause a Clearwin+ error. However, if a
grave accent modifier is specified (%`eq), the error will be suppressed.
Excessive nesting of constructs such as 'sup' or 'sub', that reduce the font
size, may result in unreadable equations.
Here are a few well known equations and chemical formulae as examples:
WINAPP
INTEGER i,w,winio@
CHARACTER*80 s(4)
s(1)='H{sub 2}SO{sub 4}'< BR> s(2)='E=mc{sup 2}'<
BR> s(3)='{del}.B=0'
s(4)=
+'{sum n=1;{infinity}}{divide 1;n{sup 2}}={divide {pi}{sup 2};6}'
i=winio@('%ca[Equations]%bg[grey]&')
DO i=1,4
w=winio@('%ob%eq@%cb&',s(i),0,0)
ENDDO
w=winio@(' ')
END
Equations are constructed using symbols from the Times New Roman and Symbol
fonts.
These same equation strings may be used in hypertext (%ht) embedded between
<equation> and </equation>. The string between these delimiters is
treated as a pure equation  no markup codes are recognised. So, for example,
the '<' symbol should be written as it is.