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#154 integrate does not produce asinh ←	↑	→ #156 Axiom crashes when compiling simple Taylor code

#155 failed coercion between Expression Fraction Integer and Expression Float in exponents

Edit detail for #155 failed coercion between Expression Fraction Integer and Expression Float in exponents revision 1 of 2

	1 2
Editor: Time: 2007/11/17 21:59:17 GMT-8
Note: Is Axiom confused? I am.

changed:
-
This fails
\begin{axiom}
exp(-0.02*t)
% :: Expression Fraction Integer
% :: Expression Float
\end{axiom}

But this works
\begin{axiom}
exp(-1*(1/50)*t)
% :: Expression Float
\end{axiom}

Why are these expressions treated differently?

How can convert the first one to the second?

From unknown Tue May 10 17:54:24 -0500 2005
From: unknown
Date: Tue, 10 May 2005 17:54:24 -0500
Subject: EXPR FRAC INT doesn't coerce to EXPR FLOAT
Message-ID: <20050510175424-0500@page.axiom-developer.org>

\begin{axiom}
(1/2*x)::EXPR FRAC INT
%::EXPR FLOAT
\end{axiom}

From BillPage Tue May 10 18:35:04 -0500 2005
From: Bill Page
Date: Tue, 10 May 2005 18:35:04 -0500
Subject: Is Axiom confused? I am.
Message-ID: <20050510183504-0500@page.axiom-developer.org>

If
\begin{axiom}
exp(-0.02*t) :: Expression Fraction Integer
\end{axiom}
then why?
\begin{axiom}
exp(-1*(1/50)*t)
\end{axiom}
Is Axiom confused about the definition of the type
Expression Integer? What exactly is it that is supposed
to be an Integer in each case above?

This fails

axiom
exp(-0.02*t)

(1)

Type: Expression Float

axiom
% :: Expression Fraction Integer

(2)

Type: Expression Fraction Integer

axiom% :: Expression Float
   Cannot convert from type Expression Fraction Integer to Expression 
      Float for value
        1
     - -- t
       50
   %e

But this works

axiom
exp(-1*(1/50)*t)

(3)

Type: Expression Integer

axiom
% :: Expression Float

(4)

Type: Expression Float

Why are these expressions treated differently?

How can convert the first one to the second?

EXPR FRAC INT doesn't coerce to EXPR FLOAT --unknown, Tue, 10 May 2005 17:54:24 -0500 reply

axiom
(1/2*x)::EXPR FRAC INT

(5)

Type: Expression Fraction Integer

axiom%::EXPR FLOAT
   Cannot convert from type Expression Fraction Integer to Expression 
      Float for value
   1
   - x
   2

Is Axiom confused? I am. --Bill Page, Tue, 10 May 2005 18:35:04 -0500 reply

axiom
exp(-0.02*t) :: Expression Fraction Integer

(6)

Type: Expression Fraction Integer

then why?

axiom
exp(-1*(1/50)*t)

(7)

Type: Expression Integer

Is Axiom confused about the definition of the type Expression Integer? What exactly is it that is supposed to be an Integer in each case above?