What makes things Listable?

*To*: mathgroup at smc.vnet.net*Subject*: [mg26302] What makes things Listable?*From*: Chris Johnson <cjohnson at shell.faradic.net>*Date*: Sun, 10 Dec 2000 00:20:11 -0500 (EST)*Sender*: owner-wri-mathgroup at wolfram.com

I'm using the "Finance Essentials" package and want to use the Value command over a list of bonds. For those not familiar with the package, there is a structure called Bonds which defines the coupon, maturity, etc. for a bond. The Value command takes three arguements, Bond, SettlementDate, YieldToMaturity and returns a price. Having vectors of Bonds, Dates, and Yields, I want to create a vector of prices. My first guess was to try the following command: Value[Transpose[{bondlist,datelist,yields}]] This returned the result Value[{{bond[1],valdate[1],yield[1]},...}] My next step was to use Map[Value,Transpose[...]] which returned a list like {Value[{bond,valdate,ytm}],...} where the parameters for Value are surrounded by curly braces. Value wouldn't evaluate over parameters in this form. The solution I found for now is to create my own fuction cjValueList[{x_,y_,z_}]:=Value[x,y,z] and then mapping cjValueList provides the table I seek. I have run into this general problem of wanting to get rid of the outer level of curly braces before, and wonder if there is a more general solution then this hack redefinition of the function? Thanks, Chris Johnson

**Follow-Ups**:**Re: What makes things Listable?***From:*"Carl K. Woll" <carlw@u.washington.edu>