Next: Mathieu Functions, Previous: Legendre Functions and Spherical Harmonics, Up: Special Functions [Index]

Information on the properties of the Logarithm function can be found in
Abramowitz & Stegun, Chapter 4. The functions described in this section
are declared in the header file `gsl_sf_log.h`.

- Function:
*double***gsl_sf_log***(double*`x`) - Function:
*int***gsl_sf_log_e***(double*`x`, gsl_sf_result *`result`) These routines compute the logarithm of

`x`,*\log(x)*, for*x > 0*.

- Function:
*double***gsl_sf_log_abs***(double*`x`) - Function:
*int***gsl_sf_log_abs_e***(double*`x`, gsl_sf_result *`result`) These routines compute the logarithm of the magnitude of

`x`,*\log(|x|)*, for*x \ne 0*.

- Function:
*int***gsl_sf_complex_log_e***(double*`zr`, double`zi`, gsl_sf_result *`lnr`, gsl_sf_result *`theta`) This routine computes the complex logarithm of

*z = z_r + i z_i*. The results are returned as`lnr`,`theta`such that*\exp(lnr + i \theta) = z_r + i z_i*, where*\theta*lies in the range*[-\pi,\pi]*.

- Function:
*double***gsl_sf_log_1plusx***(double*`x`) - Function:
*int***gsl_sf_log_1plusx_e***(double*`x`, gsl_sf_result *`result`) These routines compute

*\log(1 + x)*for*x > -1*using an algorithm that is accurate for small*x*.

- Function:
*double***gsl_sf_log_1plusx_mx***(double*`x`) - Function:
*int***gsl_sf_log_1plusx_mx_e***(double*`x`, gsl_sf_result *`result`) These routines compute

*\log(1 + x) - x*for*x > -1*using an algorithm that is accurate for small*x*.