Numerical integration direct from the keyboard?

[Tim Wessman]

You are probably looking at the help for this:

"Syntax:
∫(Expr, Var, Val1, Val2)

Returns the integral of an expression.

With one expression as argument, returns the indefinite integral with respect to x. With the optional second, third and fourth arguments you can specify the variable of integration and the bounds for a definite integral.


Example:
∫(2*X,X,0,3) → 9"

Note that ∫ is not the same command as int(). Not sure if you dug into the catalog to find it, or where you got to there as the menus and templates all refer to the int( ) function instead.

∫ really was left in as a compatibility call only. internally, it just calls int( ) and then approximates at the end.

You can do the same thing by just putting . anywhere in your int command. int(2*x,0.,3) spits out "9." <--- the dot means an approximation has taken place as you no longer have a symbolic object, but an approximated number.