all functions - l


    z = l2ll(x)  

convert 2-by-dims 32 bit integer X to 64 bit integer  
(only works if sizeof(long)=8)  
 Interpreted function, defined at i/idlsave.i   line 316  




     Interpreted function, defined at i/demo3.i   line 78  




Given the coefficients a(1:m+1) of the m'th degree  
complex polynomial Sum(a(i)*x^(i-1)) and a guess x, returns a root.  
See Numerical Recipes (Press, et. al., Cambridge Univ. Press 1988),  
section 9.5.  
Interpreted function, defined at i/zroots.i   line 70  




     Interpreted function, defined at i/demo2.i   line 158  




returns the LCM (least common multiple) of A and B, which must  
be one of the integer data types.  A and B may be conformable  
arrays; the semantics of the lcm call are the same as any other  
binary operation.  
The absolute values of A and B are taken before the operation  
commences; if either A or B is 0, the return value will be 0.  
Interpreted function, defined at i/gcd.i   line 47  

SEE ALSO: gcd,   is_prime,   factorize  



Prints the legal details of Yorick's copyright, licensing,  
and lack of warranty.  
Interpreted function, defined at i0/std.i   line 88  

SEE ALSO: copyright,   warranty  


    legndr(l,m, x)  

return the associated Legendre function Plm(x).  The X may  
be an array (-1<=x<=1), but L and M (0<=M<=L) must be scalar  
values.  For m=0, these are the Legendre polynomials Pl(x).  
Relation of Plm(x) to Pl(x):  
  Plm(x) = (-1)^m (1-x^2)^(m/2) d^m/dx^m(Pl(x))  
Relation of Plm(x) to spherical harmonics Ylm:  
  Ylm(theta,phi)= sqrt((2*l+1)(l-m)!/(4*pi*(l+m)!)) *  
                      Plm(cos(theta)) * exp(1i*m*phi)  
Interpreted function, defined at i/legndr.i   line 12  

SEE ALSO: ylm_coef  



print the Y_SITE/i/README file at the terminal.  
Interpreted function, defined at i0/std.i   line 2442  



    light3, ambient=a_level,  

  Sets lighting properties for 3D shading effects.  
  A surface will be shaded according to its to its orientation  
  relative to the viewing direction.  
  The ambient level A_LEVEL is a light level (arbitrary units)  
  that is added to every surface independent of its orientation.  
  The diffuse level D_LEVEL is a light level which is proportional  
  to cos(theta), where theta is the angle between the surface  
  normal and the viewing direction, so that surfaces directly  
  facing the viewer are bright, while surfaces viewed edge on are  
  unlit (and surfaces facing away, if drawn, are shaded as if they  
  faced the viewer).  
  The specular level S_LEVEL is a light level proportional to a high  
  power spower=N of 1+cos(alpha), where alpha is the angle between  
  the specular reflection angle and the viewing direction.  The light  
  source for the calculation of alpha lies in the direction XYZ (a  
  3 element vector) in the viewer's coordinate system at infinite  
  distance.  You can have ns light sources by making S_LEVEL, N, and  
  XYZ (or any combination) be vectors of length ns (3-by-ns in the  
  case of XYZ).  (See source code for specular_hook function  
  definition if powers of 1+cos(alpha) aren't good enough for you.)  
  With no arguments, return to the default lighting.  
  light3, diffuse=.1, specular=1., sdir=[0,0,-1]  
    (dramatic "tail lighting" effect)  
  light3, diffuse=.5, specular=1., sdir=[1,.5,1]  
    (classic "over your right shoulder" lighting)  
  light3, ambient=.1,diffuse=.1,specular=1.,  
    (two light sources combining previous effects)  
  Interpreted function, defined at i/pl3d.i   line 262  

SEE ALSO: rot3,   save3,   restore3  


    lightwf, cmax  

Sets the cmax= parameter interactively, assuming the current  
3D display list contains the result of a previous plwf call.  
This changes the color of the brightest surface in the picture.  
The darkest surface color can be controlled using the ambient=  
keyword to light3.  
Interpreted function, defined at i/plwf.i   line 131  

SEE ALSO: plwf,   light3  


    limit3, xmin,xmax, ymin,ymax  
 or limit3, xmin,xmax, ymin,ymax, zmin,zmax  

Set the 3D axis limits for use with the cage.  
Use keyword aspect=[ax,ay,az] to set the aspect ratios of the  
cage to ax:ay:az -- that is, the ratios of the lengths of the  
cage axes will become ax:ay:az.  
Interpreted function, defined at i/pl3d.i   line 181  

SEE ALSO: cage3,   range3,   plwf,   plwf,   orient3  


 or limits, xmin, xmax, ymin, ymax,  
    square=0/1, nice=0/1, restrict=0/1  
 or old_limits= limits()  
 or limits, old_limits  

In the first form, restores all four plot limits to extreme values.  
In the second form, sets the plot limits in the current coordinate  
system to XMIN, XMAX, YMIN, YMAX, which may be nil or omitted to  
leave the corresponding limit unchanged, a number to fix the  
corresponding limit to a specified value, or the string "e" to  
make the corresponding limit take on the extreme value of the  
currently displayed data.  
If present, the square keyword determines whether limits marked  
as extreme values will be adjusted to force the x and y scales  
to be equal (square=1) or not (square=0, the default).  
If present, the nice keyword determines whether limits will be  
adjusted to nice values (nice=1) or not (nice=0, the default).  
There is a subtlety in the meaning of "extreme value" when one  
or both of the limits on the OPPOSITE axis have fixed values --  
does the "extreme value" of the data include points which  
will not be plotted because their other coordinate lies outside  
the fixed limit on the opposite axis (restrict=0, the default),  
or not (restrict=1)?  
If called as a function, limits returns an array of 5 doubles;  
OLD_LIMITS(1:4) are the current xmin, xmax, ymin, and ymax,  
and int(OLD_LIMITS(5)) is a set of flags indicating extreme  
values and the square, nice, restrict, and log flags.  
In the fourth form, OLD_LIMITS is as returned by a previous  
limits call, to restore the limits to a previous state.  
In an X window, the limits may also be adjusted interactively  
with the mouse.  Drag left to zoom in and pan (click left to zoom  
in on a point without moving it), drag middle to pan, and click  
(and drag) right to zoom out (and pan).  If you click just above  
or below the plot, these operations will be restricted to the  
x-axis; if you click just to the left or right, the operations  
are restricted to the y-axis.  A ctrl-left click, drag, and  
release will expand the box you dragged over to fill the plot  
(other popular software zooms with this paradigm).  If the  
rubber band box is not visible with ctrl-left zooming, try  
ctrl-middle or ctrl-right for alternate XOR masks.  Such  
mouse-set limits are equivalent to a limits command specifying  
all four limits EXCEPT that the unzoom command can revert to  
the limits before a series of mouse zooms and pans.  
Holding the shift key and pressing the left mouse button is  
equivalent to pressing the middle mouse button.  Similarly,  
pressing meta-left is equivalent to the right button.  This  
permits access to the middle and right button functions on  
machines (e.g.- most laptops) with two button or one button  
The limits you set using the limits or range functions carry over  
to the next plot -- that is, an fma operation does NOT reset the  
limits to extreme values.  
Builtin function, documented at i0/graph.i   line 771  

SEE ALSO: plsys,   range,   logxy,   zoom_factor,   unzoom,   plg,   viewport  



returns natural log of the gamma function.  
Error is less than 1e-13 for real part of z>=1.  
Use lngamma if you know that all z>=1, or if you don't care much about  
accuracy for z<1.  
Interpreted function, defined at i/gamma.i   line 16  

SEE ALSO: lngamma,   bico,   beta  



returns natural log of the gamma function.  
Error is less than 1e-13 for real part of x>=1.  
Use ln_gamma if some x<1.  
Interpreted function, defined at i/gamma.i   line 37  

SEE ALSO: ln_gamma,   bico,   beta  



returns the natural logarithm of its argument (inverse of exp).  
Builtin function, documented at i0/std.i   line 660  

SEE ALSO: log1p,   log10,   exp,   asinh,   acosh,   atanh  



returns the base 10 logarithm of its argument (inverse of 10^x).  
Builtin function, documented at i0/std.i   line 666  

SEE ALSO: log,   exp,   asinh,   acosh,   atanh  



return log(1+X) accurate to machine precision (even for X<<1)  
from Goldberg, ACM Computing Surveys, Vol 23, No 1, March 1991,  
  apparently originally from HP-15C Advanced Functions Handbook  
Interpreted function, defined at i0/std.i   line 684  

SEE ALSO: expm1,   log1p  


    logxy, xflag, yflag  

sets the linear/log axis scaling flags for the current coordinate  
system.  XFLAG and YFLAG may be nil or omitted to leave the  
corresponding axis scaling unchanged, 0 to select linear scaling,  
or 1 to select log scaling.  
Builtin function, documented at i0/graph.i   line 848  

SEE ALSO: plsys,   limits,   range,   plg,   gridxy  



     Interpreted function, defined at i/kepler.i   line 474  




     Interpreted function, defined at i/kepler.i   line 481  




     Interpreted function, defined at i/ylmdec.i   line 360  



    files = lsdir(directory_name)  
 or files = lsdir(directory_name, subdirs)  

List DIRECTORY_NAME.  The return value FILES is an array of  
strings or nil; the order of the filenames is unspecified;  
it does not contain "." or ".."; it does not contain the  
names of subdirectories.  If SUBDIRS is given and is a simple  
variable name, it is set to a list of subdirectory names (or  
nil if there are no subdirectories).  
If DIRECTORY_NAME does not exist, the return value is the  
integer 0 rather than nil.  
Builtin function, documented at i0/std.i   line 2464  

SEE ALSO: cd,   mkdir,   rmdir,   get_cwd,   get_home