Add documentation for math.analysis

extra/math/analysis/analysis-docs.factor

@@ -0,0 +1,24 @@
+USING: help.markup help.syntax math ;
+IN: math.analysis
+
+HELP: gamma
+{ $values { "x" number } { "y" number } }
+{ $description "Gamma function; an extension of factorial to real and complex numbers." } ;
+
+HELP: gammaln
+{ $values { "x" number } { "gamma[x]" number } }
+{ $description "An alternative to " { $link gamma } " when gamma(x)'s range varies too widely." } ;
+
+HELP: nth-root
+{ $values { "n" integer } { "x" number } { "y" number } }
+{ $description "Calculates the nth root of a number, such that " { $snippet "y^n=x" } "." } ;
+
+HELP: exp-int
+{ $values { "x" number } { "y" number } }
+{ $description "Exponential integral function." }
+{ $notes "Works only for real values of " { $snippet "x" } " and is accurate to 7 decimal places." } ;
+
+HELP: stirling-fact
+{ $values { "n" integer } { "fact" integer } }
+{ $description "James Stirling's factorial approximation." } ;
+