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PLegendre_d1
Compute all the unnormalized Legendre polynomials and first derivatives.
Usage
p, dp = PLegendre_d1 (lmax, z)
Returns
p: float, dimension (lmax+1)- An array of unnormalized Legendre polynomials up to degree
lmax. Degreelcorresponds to array indexl. dp: float, dimension (lmax+1)- An array of the first derivatives of the unnormalized Legendre polynomials up to degree
lmax. Degreelcorresponds to array indexl.
Parameters
lmax: integer- The maximum degree of the Legendre polynomials to be computed.
z: float- The argument of the Legendre polynomial.
Description
PLegendre_d1 will calculate all of the unnormalized Legendre polynomials and first derivatives up to degree lmax for a given argument. These are calculated using a standard three-term recursion formula, and the integral of the Legendre polynomials over the interval [-1, 1] is 2/(2l+1). Note that the derivative of the Legendre polynomials is calculated with respect to its arguement z, and not latitude or colatitude. If z=cos(theta), where theta is the colatitude, then it is only necessary to multiply dp by -sin(theta) to obtain the derivative with respect to theta.
See also
plbar, plbar_d1, plmbar, plmbar_d1, plon, plon_d1, plmon, plmon_d1, plschmidt, plschmidt_d1, plmschmidt, plmschmidt_d1, plegendre, plegendrea, plegendrea_d1
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