<%
if isVariableDefined[equations] and trim[equations] != ""
{
if (equations =~ %r/=/)
{
equations =~ %s/=/===/g
equations =~ %s/^\s*\/\/(.*)//mg // Skip commented-out lines
equations =~ %s/^[\r\n\s]+//s // Remove leading whitespace
equations =~ %s/[\r\n\s]+$//s // Remove trailing whitespace
equations =~ %s/[\r\n]+/,/sg
// println[equations]
str = "new System[[
$equations], []]"
// println[str]
system = unsafeEval[str]
// println[system]
eqs = system.solveAll[]
if solveFor
eqs = system.solveFor[solveFor]
println["<P><B>Solution:</B></P><P CLASS=\"code\"><CODE>"]
for eq = eqs
if f
println[HTMLEncode[inputFormUnicode[eq]] + "<BR>"]
else
println[formatExpressionSymbolic[inputFormUnicode[eq]] + "<BR>"]
println["</CODE></P>"]
} else
{
println["<P><I>No equals sign present. This is probably not a system of equations. </I></P>"]
}
}
/* All of the following code is to detect variable names in the
resulting solutions and create HTML forms to allow the user to
optionally plug in values for each variable (or leave them symbolic)
and evaluate the result symbolically and numerically. */
if isVariableDefined["equations"] and trim[equations] != "" and ev // Evaluate result?
{
println["""<DIV CLASS="back"><P><A NAME="Evaluated"><B>Evaluated result:</B></A></P>"""]
symbols = new set
for eq = eqs
symbols = union[symbols, getSymbols[eq]]
symbols.remove[solveFor]
repstr = ""
repls = new array
println["""<TABLE BORDER=1 STYLE="width: 100%"><TR><TH>Sym<TH>Symbolic?<TH>Value"""]
for sym = lexicalSort[symbols]
{
selvar = "sel_
$sym"
varname = "val_
$sym"
sch = eval[selvar] == "S" ? "checked" : ""
lch = eval[selvar] == "L" ? "checked" : ""
if (! sch AND ! lch)
sch = "checked"
if sch
repstr = repstr + "
$sym = noEval[
$sym]\n"
if lch
repls.push[ [constructExpression["Symbol",[sym]], eval[eval[varname]]]]
val = eval[varname] ? eval[varname] : (unit[sym] != undef ? eval[sym] : "")
valstr = HTMLEncodeQuoted[isString[val] ? val : inputFormUnicode[val]]
println[" <TR>"]
println[""" <TD>
$sym ="""]
println[""" <TD><INPUT TYPE="RADIO" NAME="
$selvar" ID="
${selvar}_S" VALUE="S"
$sch><LABEL FOR="
${selvar}_S">
$sym</LABEL>"""]
println[""" <TD><INPUT TYPE="RADIO" NAME="
$selvar" ID="
${selvar}_L" VALUE="L"
$lch>"""]
print[""" <INPUT TYPE="TEXT" autocapitalize="none" autocorrect="none" spellcheck="false" NAME="
$varname" VALUE="
$valstr" STYLE="width: 90%; box-sizing: border-box" oninput="if (this.value.trim().length != 0) {document.getElementById('
${selvar}_L').checked=true} else {document.getElementById('
${selvar}_S').checked=true; this.value=' '}">"""]
}
println["</TABLE>"]
println["""<BR>(Optional) Show result in units: <INPUT TYPE="TEXT" NAME="resultAs" ID="resultAs" VALUE="
$resultAsQuoted" autocapitalize="none" autocorrect="none" spellcheck="false"><BR>"""]
println[""" <INPUT TYPE="CHECKBOX"
NAME="conformal" ID="conformal"
$conformalChecked
onChange="this.form.submit();"><LABEL FOR="conformal">Conformal</LABEL><BR>"""]
println[""" <INPUT TYPE="CHECKBOX"
NAME="solved" ID="solved"
$solvedChecked
onChange="this.form.submit();"><LABEL FOR="solved">Fully solved</LABEL><BR>"""]
println[""" <INPUT TYPE="CHECKBOX"
NAME="showorig" ID="showorig"
$showorigChecked
onChange="this.form.submit();"><LABEL FOR="showorig">Show original equation</LABEL><BR>"""]
println["""<INPUT TYPE="Submit" VALUE="Solve">"""]
println["""<P CLASS="code"><CODE>"""]
resultAs = resultAs ? trim[resultAs] : ""
if isVariableDefined[resultAs] and resultAs != ""
{
// If resultAs has a comma like "ft, in" or "[ft, in]", or
// with quoted terms such as ["ft", "in"], then just canonify
// it to ["ft", "in"] or if it has a zero, leave that unquoted
// like ["ft", "in", 0]
// TODO: Turn this into a function
if resultAs =~ %r/,/
{
// Remove square brackets and quotes
resultAs =~ %s/[\[\]"]//g
resultAsArray = new array
for resa = split[",", resultAs] // Split on commas
{
resa = trim[resa]
if resa == "0" // Preserve literal 0 unquoted.
resultAsArray.push[0]
else
resultAsArray.push[resa]
}
resultAs = resultAsArray
}
}
//results = flatten[toArray[last]]
results = eqs
suppressed = 0
RESULT:
for eqn = rangeOf[results]
{
eq1 = results@eqn
varlen = 1
// Evaluate right-hand sides of solved equations
preamble = ""
// This matches a solved equation
if structureEquals[_a === _b, eq1]
{
preamble = preamble + getChild[eq1, 0] + " = "
part = getChild[eq1, 1]
varlen = length[inputFormUnicode[getChild[eq1,0]]]
if showorig
{
if f
preamble = preamble + HTMLEncode[inputFormUnicode[getChild[eq1,1]]] + "<BR>"
else
preamble = preamble + formatExpressionSymbolic[inputFormUnicode[getChild[eq1,1]]] + "<BR>"
preamble = preamble + repeat[" ", varlen] + " = "
}
} else
part = eq1
for [e1, e2] = repls
part = substituteExpression[part, e1, e2]
repstr2 = repstr + inputFormUnicode[part]
pe = eval[repstr2, false, true]
// println["pe=
$pe, type=" + type[pe] + ", resultAs=
$resultAs, eval=" + eval[eval[resultAs]]]
if ! structureEquals[pe, part]
if f
preamble = preamble + HTMLEncode[inputFormUnicode[part]] + "<BR>" + repeat[" ", varlen + 1] + "= "
else
preamble = preamble + formatExpressionSymbolic[inputFormUnicode[part]] + "<BR>" + repeat[" ", varlen + 1] + "= "
if solved && !isUnit[pe]
{
suppressed = suppressed + 1
next RESULT
}
if isVariableDefined[resultAs] and resultAs != "" and isUnit[pe]
{
if conformal
if ! (pe conforms eval[eval[resultAs]])
{
suppressed = suppressed + 1
next RESULT
}
if pe conforms eval[eval[resultAs]]
result = (pe -> resultAs)
else
result = inputFormUnicode[pe]
result = HTMLEncode[result]
result = formatExpression[result]
result =~ %s/\n/<BR>\n/mg
result =~ %s/\s/ /g
} else
{
if conformal && isVariableDefined[resultAs] and resultAs != ""
{
suppressed = suppressed + 1
next RESULT
}
if f
result = HTMLEncode[inputFormUnicode[pe]]
else
if solved
result = formatExpression[outputForm[pe]]
else
result = formatExpressionSymbolic[inputFormUnicode[pe]]
}
println[preamble]
println[result + "<BR>"]
if eqn < length[results]-1
println["<BR>"]
}
println["</CODE>"]
if (suppressed > 0)
println["<I>
$suppressed items suppressed because of above options.</I>"]
println["</P></DIV></FORM>"]
}
%>