 Dataplot Vol 2 Vol 1

# LAMBDAP

Name:
LAMBDAP (LET)
Type:
Library Function
Purpose:
Compute the derivative of the lambda function.
Description:
The lambda function is defined as: where v is the order of the lambda function, is the gamma function, and is the Bessel function of the first kind. Dataplot supports a maximum order of 500.

The derivative of the lambda function can be defined in terms of the lambda function: Dataplot computes this function using the LAMV and LAMN routines from "Computation of Special Functions" (see the Reference section below).

Syntax:
LET <y> = LAMBDAP(<x>,<v>)             <SUBSET/EXCEPT/FOR qualification>
where <x> is a number, variable or parameter;
<v> is a number, parameter, or variable (less than 500);
<y> is a variable or a parameter (depending on what <x> and <v> are) where the computed lambda function derivative values are stored;
and where the <SUBSET/EXCEPT/FOR qualification> is optional.
Examples:
LET A = LAMBDAP(2.3,1)
LET A = LAMBDAP(X,A1)
LET X2 = LAMBDAP(X1,4) FOR X1 = 0.1 0.1 3.0
Default:
None
Synonyms:
None
Related Commands:
 LAMBDA = Compute the lambda function. GAMMA = Compute the gamma function. BESSJN = Compute the Bessel function of the first kind.
Reference:
"Computation of Special Functions", Shanjie Zhang and Jianming Jin, John Wiley and Sons, 1996, pp. 182-184.
Applications:
Special Functions
Implementation Date:
1997/12
Program:
MULTIPLOT 2 2
MULTIPLOT CORNER COORDINATES 5 5 95 95
TITLE ORDER 0
PLOT LAMBDAP(X,0) FOR X = 0 0.01 10
TITLE ORDER 1
PLOT LAMBDAP(X,1) FOR X = 0 0.01 10
TITLE ORDER 2
PLOT LAMBDAP(X,2) FOR X = 0 0.01 10
TITLE ORDER 3
PLOT LAMBDAP(X,3) FOR X = 0 0.01 10
END OF MULTIPLOT
MOVE 50 97
JUSTIFICATION CENTER
TEXT DERIVATIVE OF LAMBDA FUNCTIONS

Date created: 6/5/2001
Last updated: 4/4/2003